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BackgroundOur objective was to investigate trends over time in longevity and reasons for replacement with or without extraction of pacemaker leads after first implantation.MethodsData collected between 1984 and 2006 in the national Dutch pacemaker registry were used. This registry covered 84% of sold leads. First lead replacement with or without extraction of one or more leads implanted with a first pacemaker generator was the endpoint of interest. The time interval of and reason for first replacement were analyzed. A 7-year follow-up interval after first implantation was used to analyze changes over time.ResultsDuring 22 years of data collection, 138,225 leads were implanted with a first pacemaker generator. Within a mean 5.5 (SD 4.4) years for 7,377 patients one or more leads were extracted for the first time. In total, 8,849 leads (6.4%) were replaced or extracted. The main reasons for first replacement of leads with or without extraction were insulation failures (14.6%), infection (8.8%), displacement (7.6%), or for elective reasons (10.0%). The number of insulation failures peaked during 1991-1995.ConclusionsDespite improvements in pacing techniques and experience with cardiac devices, we found that insulation and conductor failures, and complications such as infections, did not diminish over the 20 years of the registry. Continuing attention in clinical practice for the evaluation of these adverse outcomes and maintaining quality registries is warranted, whereas manufacturers should use this information to further improve their devices.

Aims: After decades of experience and strongly improved technology, service time of pacemaker generators is expected to increase. To test this hypothesis, we conducted a retrospective review of a large cohort of patients with a pacemaker.Methods: We reviewed data collected between 1984 and 2006 in the first national Dutch pacemaker registry. This registry covered 96% of all generators implanted. We analysed the time of and reason for explantation of pacemaker generators. A 7-year follow-up interval after first implantation and following replacements was used to analyse changes over time.Results: During 22 years of data collection, nearly 97,000 first pacemaker generators were implanted. A total of 27,937 (22.4%) generators were explanted within a mean of 6.3 (standard deviation 3.3) years. Reasons for approximately 60% of these explantations were ` end of life' of the pacemaker generator or elective system change. Complications or failures such as infections and recalls accounted for approximately 20% of the explantations. For the remaining 20%, the reasons for explantation had not been registered.Conclusion: Despite progress in technology, a substantial proportion of pacemaker generators is explanted before its expected service time, with one in five generators being replaced due to technical failures, infections or other complications. Furthermore, the time interval between pacemaker implantation and explantation due to normal 'end of life' (battery EOL) decreased. Infections continue to rank highly as a cause for pacing system replacement, despite all current preventive measures.

The implantation of cardiac pacemakers has become a well-established therapy for conduction disorders and sinus node dysfunction. In many countries pacemaker registries have been initiated in order to collect information on patient characteristics, trends in numbers and the types of pacemakers used, to identify problematic devices, and for safety monitoring. For this utilisation study the Central Pacemaker Patients Registration (CPPR) from the Netherlands Pacemaker Registry Foundation (CPPR-SPRN) containing data collected for more than 20 years was used. During this period nearly 97,000 first pacemakers were implanted. Analyses show an increase in the rate of implanted devices. The change in pacemaker type from VVI to DDD, followed by biventricular stimulation, is reflected by the number of simultaneously implanted leads, which is partly a consequence of cardiac resynchronisation therapy. Our data demonstrate that indications for implantation and type of pacemaker are comparable with other European countries.

Myocardial perfusion SPECT (MPS) is frequently used for cardiovascular risk stratification. The significance of MPS in patients with abnormal electrical ventricular activation is often questionable. This review assesses the value of MPS for risk stratification of patients with intrinsic left bundle branch block or that due to right ventricular apical pacing. We reviewed the literature by a search of the MEDLINE database (January 1980 to September 2010). The terms prognosis or prognostic value were combined with SPECT and LBBB or pacing or pacemakers. MPS was categorised as low and high risk according to the original definitions. We identified 11 studies suitable for review. A low-risk MPS is associated with a low risk of cardiac events whereas high-risk MPS carries a 4.8-fold increased risk, 95% CI [3.2 - 7.2] (p < 0.0001). Despite secondary prevention and an improved medical and interventional care, these figures have hardly changed over time. A low-risk MPS permits a policy of watchful waiting whereas a high-risk MPS requires further analysis and treatment. The persistent high cardiac death and acute myocardial infarction rate after a high-risk MPS suggest that the current management of these patients does not suffice and needs reconsideration.

Remote monitoring of implanted cardiac devices is an evolving method for regular checks of their electronic integrity and functioning. The communication with the devices is carried out unsupervised with wireless trans-telephonic or cable-dependent linkage. The interrogation of the device examines several programmed functions and harvests the stored data of numerous events. The collected data constitute the base to decide whether the implanted device is operating properly and can give some information about the physical condition of the device recipient. Preliminary short-term results show favourable effects in terms of safety and cost and time saving as compared with the current face-to-face visits of conventional patient follow-ups. Remote monitoring of implanted devices will extend markedly in the coming years and its development touches many questions ranging from technical accuracy, patient benefit, cost-effectiveness and responsibilities of the provider and receivers of the delivered device data, to the role of the cardiologist and allied professionals and of course privacy rules. In this point of view, these questions are discussed in order to explore the consequences of device remote monitoring with nationwide Trials. (Neth Heart J 2009;17:434-7.19949713)

Background. Correct pacemaker (PM) diagnosis of paroxysmal atrial tachyarrhythmias is crucial for their prevention and intervention with specific atrial pacing programmes. The PM mode switch to only ventricular pacing after detection of atrial tachyarrhythmias is often used as the parameter to quantify the ‘burden’ of atrial tachyarrhythmias. Objectives. This review addresses potential errors in the detection and diagnosis of atrial tachyarrhythmias, sometimes resulting in incorrect mode switches. The interpretation of PM-stored data of patients with atrial tachyarrhythmias and the results of trials of pace prevention and intervention can be better appreciated with more insight into the technical options and pitfalls. Results. Literature and clinical experience demonstrate that the correctness of PM-derived diagnosis of atrial tachyarrhythmias depends on 1) the sensitivity setting to detect the onset and perpetuation of atrial tachyarrhythmias frequently characterised by variable and low-voltage signals, 2) the rejection of far-field R wave sensing by the atrial sense amplifier, 3) the facility for verification of mode switches by a high-quality intracardiac registration of the nonmodified atrial electrogram. The configuration of the atrial lead also contributes to the diagnostic performance of the PM. Conclusion. Not only pacing algorithms and diverse technical PM features but also the atrial lead configuration are currently the limiting factors to the fully reliable, automated detection and diagnosis of atrial tachyarrhythmias. If these technical shortcomings can be improved, better signal processing will result. Then atrial pacing to prevent or suppress atrial tachyarrhythmias will be more justified. (Neth Heart J 2008;16:201-10.)

The diagnostic programmes of modern pacemakers have increased our knowledge of atrial tachyarrhythmias (ATAs) in chronically paced patients. These programmes also support the evaluation of the effects of pharmacological treatment of ATAs. The success of interruption and/or prevention of ATAs with pacemakers depends strongly on the diagnostic accuracy and the properties of the pacing algorithms, their individual programming and the site and configuration of the pacing leads. Atrial septum pacing can be beneficial in patients with paroxysmal atrial fibrillation and prolonged P wave duration. Recent large-scale studies on preventive and interruptive atrial pacing of ATAs show modestly positive or no results. Therefore, atrial pacing therapy for ATAs should be considered cautiously, serving as an adjuvant to pharmacological treatment rather than as a primary intervention. This also applies for pacing interventions for ATAs in cardiac resynchronisation therapy. The pacemaker algorithms for the detection of ATAs and atrial lead configuration are crucial for the success of pacemaker-mediated prevention or interruption of ATAs. The success of these interventions is dependant on future improvements of pacemaker technology. (Neth Heart J 2008;16 (suppl 1): S20-S24.)

Aims Despite an annual rise in the numbers of patients receiving their first pacemaker (PM), the risks of the implantation procedure remains unclear. The purpose of this prospective study is to estimate the incidence of in-hospital events after first PM implantation and to determine the predictors of these events. Methods and results Patients with conventional pacing diagnosis were included in the Dutch multicentre FOLLOWPACE PM registry that prospectively documented patients’ prognosis and quality of life, and PM events after first implantation. From these registry characteristics, implantation data and in-hospital findings were analysed as potential predictors for events in a sample of 1198 patients. In 111 patients studied, at least one serious in-hospital event occurred (incidence 10.1%, 95%CI: 8.9–12.3). Six variables, i.e. a lower body mass index, presence of heart failure in medical history, main indication for implantation, vena subclavia use for venous access, active atrial lead fixation, and the implantation of a dual chamber system, were found to be independent predictors of events after first PM implantation. The overall multivariable model yielded an ROC area of 0.65 (95%CI: 0.60–0.70). Conclusion This large prospective multicentre study identified six variables as independent predictors for serious in-hospital events after first implantation. This may assist the implanting cardiologist and surgeon to identify patients at higher risk, during and immediately after PM implantation.

Literature about pacemaker (PM) implantations shows that several clinical and technical factors determine the short- and long-term complications after the intervention. Annual hospital volume, however, does not negatively affect complications in contrast with the cumulative experience of the operator. In view of this observation, the current required number of 20 to 30 first PM implantations for cardiology training does not match standards for quality of care. In addition, concentration of implants and replacement of pacemakers to a limited number of operators per hospital to comply with the increasing demands of patients and other parties has to be seriously considered.

Objective: Of this study was to investigate three groups of highly trained competitive endurance athletes consisting of marathon runners, triathletes and cyclists for differences in left ventricular adaptation. Methods: 25 marathon athletes, 21 triathlon athletes and 38 cyclists underwent a standard echocardiographic and Doppler study. Results: The left ventricular internal diameter in diastole divided by body surface area was significantly larger in cyclists than in marathon runners (31.6 ± 3.0 vs. 30.0 ± 2.0 mm/m2, p < 0.05) but did not differ of that of triathletes. Left ventricular mass was significantly different between marathon runners and triathletes (253.6 ± 63.7 vs. 322.0 ± 62.1 g, p < 0.005) and between marathon runners and cyclists (253.6 ± 63.7 vs. 314.2 ± 79.2 g, p < 0.005). Systolic wall stress was significantly different between the marathon runners and the triathletes (88.4 ± 11.7 vs. 78.9 ± 11.0 g/cm2 p < 0.05). Only a minority of the endurance athletes showed concentric remodeling (7%), whereas a majority showed eccentric remodeling (65%) of the left ventricle. The prevalence of eccentric remodeling was more apparent in cyclists. There were some specific differences in left ventricular diastolic function between the three different endurance sports, but no left ventricular diastolic dysfunction could be detected. Conclusion: There is a sport-specific left ventricular adaptation in endurance athletes. The triathlon heart and the heart of a cyclist differ significantly from a marathon heart.

It is a risk for someone not an expert in arrhythmias to value the contents of the manuscripts of this issue. Although one can safely assume that the reviewing process has filtered out the most significant manuscripts, the choice of the peers often deviates from the interest of the common reader. To reach the common reader with limited arrhythmia experience, I prefer to introduce the arrhythmia studies of this issue with potential consequences for daily patient care rather than giving an in depth description of their contribution to arrhythmia subspecialties and scientific impact.

Background —Radiofrequency (RF) catheter ablation provides curative treatment for idiopathic ventricular tachycardia (VT). Methods and Results —Nineteen consecutive patients with an idiopathic VT underwent RF catheter ablation. An integrated 3-phase mapping approach was used, consisting of the successive application of online 62-lead body surface QRS integral mapping, directed regional paced body surface QRS integral mapping, and local activation sequence mapping. Mapping phase 1 was localization of the segment of VT origin by comparing the VT QRS integral map with a database of mean paced QRS integral maps. Mapping phase 2 was body surface pace mapping during sinus rhythm in the segment localized in phase 1 until the site at which the paced QRS integral map matched the VT QRS integral map was identified (ie, VT exit site). Mapping phase 3 was local activation sequence mapping at the circumscribed area identified in phase 2 to identify the site with the earliest local endocardial activation (ie, site of VT origin). This site became the ablation target. Ten VTs were ablated in the right ventricular outflow tract, 2 at the basal LV septum, and 7 at the midapical posterior left ventricle. A high long-term ablation success (mean follow-up duration, 14±9 months) was achieved in 17 of the 19 patients (89%) with a low number of RF pulses (mean, 3.3±2.2 pulses per patient). Conclusions —This prospective study shows that integrated 3-phase mapping for localization of the site of origin of idiopathic VT offers efficient and accurate localization of the target site for RF catheter ablation.

His-bundle ablation followed by pacemaker implantation is today a widely accepted therapeutic choice when drug refractoriness of symptomatic AF is evident. The selection of pacing mode in patients suffering from paroxysmal AF is still controversial. Preservation of AV synchrony is an attractive option in patients with paroxysmal AF who undergo His-bundle ablation. The purpose of this study was to examine prospectively the contribution of VDDR pacing for preservation of AV synchrony. After His-bundle ablation a VDDR pacing system was implanted in 17 patients with paroxysmal AF, and all antiarrhythmic drugs were withdrawn. The endpoint of the study was defined as the onset of chronic AF. To document the onset of chronic AF 48-hour Holter recordings were made every 6-8 weeks. After a mean followup of 18.2 (range 14-21) months, VDDR pacing is still operative in 13 patients (77%). Four patients developed chronic AF after a mean follow-up of 6 months. Of several baseline characteristics, only the intraatrial P wave at implantation was significantly smaller in patients developing chronic AF than in patients in whom the VDDR mode is still operative. This pilot study suggests that VDDR pacing is an attractive pacing method for patients with paroxysmal AF after His-bundle ablation. A low intraatrial P wave electrogram at implant was associated with a higher risk for the development of chronic AF.

Late Results of Surgery for AF. Introduction: Currently, surgery- and catheter-mediated ablation is applied when drug refractoriness of atrial fibrillation is evident, although little is known about the long-term incidence of new atrial arrhythmia and the preservation of sinus node function. Methods and Results: To address this issue, 30 patients with successful corridor surgery for lone paroxysmal atrial fibrillation and normal preoperative sinus node function were followed in a single outpatient department. Five years after surgery, the actuarial proportion of patients with recurrence of atrial fibrillation arising in the corridor was 8%± 5%, with new atrial arrhythmias consisting of atrial flutter and atrial tachycardia in the corridor 27%± 8%, and with incompetent sinus node requiring pacing therapy 13%± 6%. Right atrial transport was preserved in 69% of the patients without recurrence of atrial fibrillation and normal sinus node function. Stroke was documented in two patients. Conclusions: Corridor surgery for atrial fibrillation is a transient or palliative treatment instead of a definitive therapy for drug refractory atrial fibrillation. This observation strongly affects patient selection for this intervention and constitutes a word of caution for other, non-pharmacologic interventions for drug refractory atrial fibrillation.

OBJECTIVE: To evaluate exercise capacity of patients with chronic atrial fibrillation in whom His bundle ablation followed by ventricular rate response pacing (VVIR) was carried out because of drug refractoriness. DESIGN: Prospective study. PATIENTS: 25 consecutive patients, all with chronic symptomatic drug refractory atrial fibrillation, underwent His bundle ablation. Before this intervention all patients were on antiarrhythmic drugs to attain acceptable heart rate control and to relief symptoms. MAIN OUTCOME MEASURES: Exercise capacity, including measurements of VO2, was examined before and after a mean interval of seven months following His bundle ablation. RESULTS: Exercise capacity after His bundle ablation increased from a mean of 109 (SD 49) W to 118 (46) W (P < 0.002), but VO2 at peak exercise did not change significantly. Maximum exercise capacity was achieved with a significantly lower maximum driven heart rate than the spontaneous heart rate before ablation. CONCLUSIONS: Exercise capacity of patients who underwent His bundle ablation followed by VVIR pacing remained unchanged or improved during a mean follow up of seven months. Larger patient populations with longer follow up are necessary to examine determinants of improved exercise capacity.

Background Postinfarction ventricular tachycardias (VTs) may degenerate into ventricular fibrillation (VF), but this does not happen in all patients. The underlying mechanism is not exactly known, but dispersion of refractory periods is considered a major factor in both induction and persistence of reentrant arrhythmias in general. Hypertrophied, noninfarcted myocardium has altered electrophysiological characteristics. We hypothesized that noninfarcted ventricular tissue may provide the heterogeneities that cause the transition from VT into VF. Local fibrillation intervals, ie, the average interval between local activations during VF, have previously been shown to correlate well with local refractoriness in human and canine atrium and in porcine and canine ventricle and may therefore be used as an index of local refractoriness. This technique permits simultaneous assessment of refractoriness at multiple sites. Methods and Results We measured local fibrillation intervals at 32 to 64 sites in the noninfarcted part of the left ventricle in patients undergoing antiarrhythmic surgery for symptomatic, drug-refractory, postinfarction ventricular tachyarrhythmias. The grid of electrodes (interelectrode distance, 7 mm) was attached to the epicardium of the left ventricle remote from the infarcted tissue. Group 1 consisted of 7 patients with hemodynamically tolerable sustained VT (VT group). Group 2 consisted of 7 patients with cardiac arrest and documented VF (VF group). With the patients on cardiopulmonary bypass, VF was induced by multiple premature stimulation. The VF interval was not significantly different in the two study groups (VT group, 136±5.5 ms; VF group, 129±3.4 ms, mean±SEM). However, spatial dispersion of the VF intervals (remote from the infarcted area) expressed as the coefficient of variation of VF intervals (SD×100/mean VF interval in each heart) was significantly larger in the VF group. It was 3.63±0.56 in the VF group and 1.55±0.40 in the VT group (mean±SEM; P P P Conclusions This study shows larger dispersion in VF intervals and therefore suggests larger dispersion of refractory periods in parts of the myocardium remote from the infarction in patients with postinfarction VF than in patients with postinfarction VT.

Remote monitoring of cardiac implanted electronic devices (CIED: pacemaker, cardiac resynchronisation therapy device and implantable cardioverter defibrillator) has been developed for technical control and follow-up using transtelephonic data transmission. In addition, automatic or patient-triggered alerts are sent to the cardiologist or allied professional who can respond if necessary with various interventions. The advantage of remote monitoring appears obvious in impending CIED failures and suspected symptoms but is less likely in routine follow-up of CIED. For this follow-up the indications, quality of care, cost-effectiveneness and patient satisfaction have to be determined before remote CIED monitoring can be applied in daily practice. Nevertheless remote CIED monitoring is expanding rapidly in the Netherlands without professional agreements about methodology, responsibilities of all the parties involved and that of the device patient, and reimbursement. The purpose of this consensus document on remote CIED monitoring and follow-up is to lay the base for a nationwide, uniform implementation in the Netherlands. This report describes the technical communication, current indications, benefits and limitations of remote CIED monitoring and follow-up, the role of the patient and device manufacturer, and costs and reimbursement. The view of cardiology experts and of other disciplines in conjunction with literature was incorporated in a preliminary series of recommendations. In addition, an overview of the questions related to remote CIED monitoring that need to be answered is given. This consensus document can be used for future guidelines for the Dutch profession.

Elevated levels of N-terminal pro BNP (NT-proBNP) excreted by stretched cardiomyocytes are attributed to increased cardiac filling pressures arising, for example, in left ventricular relaxation disorders. These conditions elicit higher atrial wall stress which in turn can initiate mechanisms causing atrial fibrillation (AF). However, the presence of AF itself can also produce increased levels of NT-proBNP, as was demonstrated by a drop of the peptide levels when sinus rhythm resumed after converted AF [1]. Not surprisingly, therefore, in the past decade NT-proBNP has received much attention as a potential new marker for AF detection and management [2]. In 2008, Asselbergs and coworkers reported data of the Groningen PREVEND study and showed that newly detected AF could be related to elevated NT-proBNP 4 years earlier at baseline [3]. A new AF-independent predictor was born but its significance was debatable for several reasons [4]. Some studies examined the relation of the duration or time of onset of AF to NT-proBNP levels, whereas other papers demonstrated variable outcomes of the relationship between success rates of AF cardioversion and the peptide levels (see publications of reference [5]). Conflicting results could not promote the role of NT-proBNP as the ideal guide for AF detection or management due to the dubious cause-effect relationship. The success rate of drug-administered cardioversion of AF depends on many factors such as gender, duration of AF, presence of structural heart disease and so forth. According to our guidelines for drug-administered cardioversion of AF (see www.NVVC.nl), intravenous flecainide, propafenone, ibutilide, or vernakalant are recommended (Class 1, level A) when pharmacological cardioversion is preferred and there is no or minimal structural heart disease. The conversion success rate of flecainide is 67–92 % at 6 hours provided AF is of 48 hours after the onset [6]. Symptomatic

BACKGROUND The purpose of this study was to assess the value of body surface mapping and the standard 12-lead ECG in localizing the site of origin of postinfarction ventricular tachycardia (VT) during endocardial pace mapping of the left ventricle. METHODS AND RESULTS Simultaneous recordings of 62-lead body surface QRS integral maps and scalar 12-lead ECG tracings were obtained in 16 patients with prior myocardial infarction during a total of 26 distinct VT configurations and during subsequent left ventricular catheter pace mapping at 9 to 24 different endocardial sites. Anatomic pacing site locations were computed by means of a biplane cineradiographic method and plotted on a polar projection of the left ventricle. The QRS integral map and the QRS complexes of the 12 standard leads of each VT morphology obtained in a particular patient were compared independently with the different paced QRS integral maps and paced QRS complexes of the 12-lead ECG generated in that same patient. The stimulus site locations of the best matching paced QRS integral map and paced QRS complexes of the 12-lead ECG were indicated on the polar projection and subsequently compared with the endocardial location of the corresponding site of VT origin identified during intraoperative (surgical ablation) or catheter activation sequence mapping (catheter ablation). The localization resolution of pace mapping was established separately for each electrocardiographic technique by computing the size of endocardial areas with similar morphological features of the QRS complex. Pace mapping advocated with body surface mapping or the 12-lead ECG enabled adequate reproduction of the VT QRS morphology in 24 of 26 VTs (92%) and 25 of 26 VTs (96%), respectively. Activation sequence mapping identified the site of origin in 12 of 26 previously observed VT configurations (46%). Ten and 11 VTs were localized by activation sequence mapping and pace mapping combined with body surface mapping or the 12-lead ECG, respectively. Pace mapping applied with body surface mapping identified the site of origin correctly (distance < or = 2 cm) in 8 of 10 compared VTs (80%); an adjacent site (distance between 2 and 4 cm) or a disparate site (distance > or = 4 cm) was identified in the remaining 2 of 10 VTs (20%). Pace mapping used with the 12-lead ECG localized the site of origin correctly in 2 of 11 VTs (18%); the site of origin was identified correctly next to an additional adjacent site in 5 of 11 VTs (55%); and an adjacent site or a disparate site was found in 1 of 11 VTs (9%) and 2 of 11 VTs (18%), respectively. The difference in localization accuracy of both electrocardiographic techniques was statistically significant (P = .02). The mean size of endocardial areas where a comparable QRS morphology was obtained during pace mapping was 6.0 +/- 4.5 cm2 with the application of body surface mapping and 15.1 +/- 12.0 cm2 with the use of the 12-lead ECG. CONCLUSIONS These results demonstrate that application of the 62-lead instead of the 12-lead ECG during endocardial pace mapping enhances the localization resolution of this mapping technique and enables more precise identification of the site of arrhythmogenesis in the majority of compared postinfarction VT episodes.

Self-terminating ventricular fibrillation was recorded in a 47 year old woman without coronary artery or other structural heart disease. Reperfusion was thought to be responsible for the ventricular fibrillation because the arrhythmia started while the ST segment was returning to the baseline during an episode of silent ischaemia that was probably caused by coronary spasm. This case shows that potentially lethal arrhythmias can arise during reperfusion and that ventricular fibrillation during reperfusion may be self-terminating.

Around 1904 remote monitoring of electrical cardiac activity was carried out for the first time by Willem Einthoven: he recorded the one-lead ECG of a patient admitted to the Leiden University Clinic in his Physiology Laboratory at a distance of 1.5 km from the hospital. Rightly he called this recording the tele-cardiogram (1). Hundred years later remote monitoring has expanded markedly by tremendous technical achievements, information technology, and the worldwide internet, components that underlie the chain between the cardiac implanted electronic device (CIED), the patient at home or outdoors, and the hospital staff responsible for technical controls. The first series of successive outcome studies indicates that remote monitoring and follow-up either at regular periods replacing the in-hospital technical controls (2), or 24-h monitoring to detect timely device failures is safe, highly reliable, prompts replies to failures, and reduces the incidence of inappropriate ICD shocks. Thus remote follow-up and monitoring can be classified as a valuable additional tool for patient care. Afterwards several randomised studies underscored this favourable outcome whereas moderate cost saving (3, 4) could be demonstrated. Consequently a consensus document for remote CIED monitoring was composed for the Dutch cardiology profession that can be applied in daily practice (5). Despite the favourable messages of these papers, several obstacles block the employment of CIED remote monitoring in Western general practice. The overwhelming amount of data that can arrive at the desk of the cardiologist or allied professional 24 h a day/7 days a week (6) and wait for reply or action or not, together with the sometimes unknown potential clinical relevance of the automated generated plots and graphs are serious pitfalls. In addition, lack of justifiable and fair reimbursement, and of legal arrangements of various parties, and in particular the contested willingness of some CIED patients to participate in remote monitoring inhibit further employment of this remote care (7). However, several studies did show obvious patient satisfaction and acceptance of remote ICD follow-up (8), while younger patients and smaller clinics (7), and probably other physical and mental characteristics, are associated with noncompliance and preference for in-hospital checks. In this issue Versteeg and co-workers present the rationale and design of the REMOTE-CIED study that attempts to establish the patient perspective on remote ICD monitoring which ‘could help to support patient-centred care in the future’ and to calculate cost effectiveness of this method (9). In this multicentre, prospective European study patients with a first ICD or CRT-ICD for primary or secondary prevention from fatal arrhythmias, and who have a left ventricular ejection fraction 2 years. To assess patient attitudes and perception of CIED remote monitoring, randomisation between in-hospital follow-up only or the combined patient remote follow-up and annual in-hospital control will be carried out. Several validated questionnaires have to be filled out at scheduled time intervals. Demographic, medical and CIED-related events and failures will be noted to determine factors associated with the perception of remote monitoring of the participants. This study is specifically focused on patient feelings because according to the investigators: ‘previous trials have fallen short in their patient-centredness and have left an important question unanswered: namely what do patients think about remote monitoring?’ (9). This is indeed true because this subject was only studied in (small) outcome studies in selected patients (8) or the patient satisfaction with telemedicine was neither clearly defined nor assessed with validated methods (10). Because patient perception about remote CIED follow-up is without doubt strongly determined by human influences - of the cardiologist, allied professional or family-, the progress of the underlying heart disease, unsatisfying contribution of CRT to the failing cardiac muscle (in about 30 %), comorbidity and negative effects of ageing, inappropriate ICD treatment and so forth, the ultimate comparison of the results of both study arms can become a scientific puzzle and not a clear yes/no answer. This potential problem can be solved by a much longer follow-up of at least 5 years that better reflects real life. Furthermore medicalisation and wish-fulfilling medicine evoked by remote monitoring and follow-up are not addressed at all in this study. Attention to these potential side effects is justified because the Western health care system is under pressure. Third, because the study will be conducted in five European countries assessment of cost-effectiveness is complex and confusing due to large variations in cost calculations of all care components in the participating countries. This part of the objectives has already been sufficiently covered showing clear cost saving in most countries (3, 4). Despite these obstacles, this study warrants implementation and participation of Dutch hospitals with a CIED license and experience because we eventually want to get validated insight into the characteristics of patients who will most profit or not from CIED remote monitoring. These data are strongly desired to also convince health insurance companies that remote ICD follow-up justifies reimbursement and promotes sustainable care with high and measurable quality. In the meantime we go forwards to encourage our CIED patients to profit from remote technical follow-up with the annual medical visit in stable patients while care of heart failure patients with CIED is routinely covered in the specific outpatient departments. In conclusion, we need more and detailed facts to convince ICD and CRT-ICD recipients that remote follow-up is worthwhile and that the patient is more than a computer file (7).

VAN DESSEL, P.F., et al.: Successful Surgical Ablation of Sustained Ventricular Tachycardia Associated with Mitral Valve Prolapse Guided by a Multielectrode Basket Catheter. Ventricular tachycardia occurs frequently in patients with mitral valve prolapse. If antiarrhythmic drug therapy fails or mitral valve surgery is indicated, concomitant arrhythmia surgery may be considered. This report describes the first clinical use of an atrial transseptally inserted multielectrode basket catheter, placed across the mitral valve, to guide intraoperative mapping and ablation of monomorphic sustained ventricular tachycardia in association with mitral valve prolapse. Endocardial covering and signal quality of this percutaneous mapping catheter were of good quality, allowing an accurate localization of the site of origin of the tachycardia.

Mechanical dyssynchrony has proven to be superior to QRS duration in predicting response to cardiac resynchronisation therapy (CRT). Whether time to peak longitudinal strain delay between the mid-septum and mid-lateral left ventricular wall better predicts CRT response than tissue Doppler imaging (TDI) is unclear. This study compares the value of the two methods for the assessment of mechanical dyssynchrony and prediction of CRT responders. 66 clinical responders and 17 nonresponders to CRT with severe systolic heart failure (LVEF 130 ms with left bundle branch block were evaluated by peak longitudinal strain and TDI. Doppler echocardiograms and electromechanical time delay (EMD) intervals were acquired before and after pacemaker implantation. In all responders EMD measured by peak longitudinal strain was >60 ms before implantation, compared with 76% of the patients measured by TDI. Nonresponders had EMD 60 ms. Peak longitudinal strain delay appears to be superior to TDI to predict the response to CRT. (Neth Heart J 2010;18:574-82.)

To improve electrocardiographic localization of the site of origin of ectopic left ventricular (LV) impulse formation in the heart with prior myocardial infarction, 62-lead body surface QRS integral maps were studied during LV pacing at a total of 221 endocardial sites in 14 patients with previous anterior (AMI), inferior (IMI), lateral (LMI), or anterior and inferior (AMI/IMI) myocardial infarction. The anatomic location of each pacing site was computed using digitized biplane fluoroscopic images and plotted on standardized LV endocardial polar projections. A data base of characteristic AMI and IMI mean QRS integral maps was developed after visually selecting subgroups with nearly identical QRS integral morphology from the ectopic activation sequences produced at 110 sites in eight patients with AMI and at 66 sites in four patients with IMI. Intrasubgroup pattern uniformity and intersubgroup pattern variability were statistically verified. The endocardial pacing site locations belonging to each AMI and IMI subgroup were depicted as segments on the respective LV polar projections. In patients with AMI, a total of 18 typical mean QRS integral patterns were obtained, whereas 22 different mean total QRS integral patterns showing more substantial intersubgroup variation were acquired in patients with IMI. Posterolateral regions exhibited a relatively low electrocardiographic sensitivity (six AMI and five IMI patterns) as compared with anteroseptal regions (12 AMI and 17 IMI patterns). Total QRS integral patterns obtained at 24 sites in one patient with LMI were largely compatible with the IMI mean total QRS integral patterns, whereas the majority of total QRS integral patterns acquired at 21 sites in one patient with AMI/IMI corresponded with the AMI mean total QRS integral patterns. The results show that total body surface QRS integral maps generated during LV pacing in patients with prior myocardial infarction cluster by pattern and that each QRS integral pattern is related to a circumscribed endocardial segment of ectopic impulse formation. The relation between a given QRS integral pattern and the position and size of the corresponding paced segment is dependent on infarct location. The present infarct-specific data base of characteristic total body surface QRS integral patterns provides a clinical tool to obtain detailed electrocardiographic localization of ventricular arrhythmias in patients with previous myocardial infarction.

Cardiac resynchronisation therapy (CRT) aims to restore left ventricular electrical/mechanical dyssynchrony, which can underlie impaired systolic left ventricular (LV) function and congestive heart failure. Several large prospective studies were able to document clearly that chronic electrical synchronisation does improve the systolic dysfunction and ameliorates symptoms, patient functioning and prognosis. If the conventional criteria are applied, this positive response can be observed in roughly 70% of patients, depending on the definition used for ‘positive response’.

Endocardial mapping of electrical activity was carried out in 150 patients to guide antiarrhythmic surgery for drug-resistant ventricular tachycardia in the chronic phase of myocardial infarction. In 20 of these patients, the activation pattern of 27 distinct tachycardias was focal and diastolic potentials were recorded at three or more sites. In 26 tachycardias, the sequence of diastolic potentials progressed from the area of latest activation of one cycle toward the “origin” of the next cycle. In two patients, the heart was stimulated during tachycardia, resulting in entrainment of the tachycardia in both. Late potentials were recorded during entrainment at sites where diastolic potentials occurred during tachycardia.In 11 of the 20 patients, endocardial mapping was performed during sinus rhythm. In four of these, late potentials were observed during sinus rhythm at sites where diastolic potentials were recorded during tachycardia. In two patients without late potentials during sinus rhythm, late potentials were observed during stimulation and induced ectopic beats.The results support the concept that the mechanism of several of these tachycardias is based on reentry in a macrocircuit comprising a tract of surviving tissue traversing the infarct and the remaining healthy tissue. They also indicate that the absence of late potentials during sinus rhythm does not guarantee the absence of arrhythmogenic pathways.

We report our combined experience with operative therapy for atrioventricular nodal tachycardia using an anatomically guided procedure. The operative rationale was to dissect the AV node with the intent of modifying perinodal tissues (skeletonization). The anterior septal and posterior septal regions were initially approached epicardially to facilitate endocardial dissection. Under normothermic cardiopulmonary bypass, the right atrial septum was mobilized and the intermediate AV node was exposed anterior to the tendon of Todaro. Ablation of concomitant accessory pathways was done prior to AV nodal skeletonization. Forty-six patients aged 9-71 years (mean 36) were operated upon. Five patients had accessory pathways in addition to AV nodal reentry. At electro-physiological study prior to discharge, no patient had an AV block although anterograde and retrograde Wenckebach cycle lengths were significantly prolonged. Ten patients had a retrograde AV block. The 46 patients were free of arrhythmia and not taking antiarrhythmic medication after a follow-up of 1-45 months (mean 17). Three patients had a recurrence of the tachycardia 10 days, 2 months and 7 months post-operatively, respectively. All patients had a subsequently successful reoperation.

Aims This communication describes the design of the FOLLOWPACE study. The overall aim of FOLLOWPACE is to quantify the cost-effectiveness of routine follow-up visits in patients with a pacemaker (PM). Specific aims are (i) to quantify the incidence of complications and the quality of life 1 year after PM implantation; (ii) to quantify which baseline characteristics measured during implantation are predictors of the occurrence of complications and quality of life after 1 year; (iii) to determine the added predictive value of follow-up measurements to improve the efficiency of follow-up and to demonstrate which follow-up measurements are redundant. Methods and results FOLLOWPACE is a prospective, observational, prognostic cohort study. About 40 PM centres in the Netherlands will participate to include about 2500 patients. Each patient aged � 18 receiving a PM for the first time is eligible. At baseline, i.e. time of implantation, all potential predictors of complications and quality of life after 1 year are documented. After implantation, follow-up visits will be carried out conforming with routine care, usually three in the first year. At these visits, other potential prognostic predictors will be documented. Primary outcome is the incidence of PM- or cardiac complications at 1 year. Secondary outcome parameters are quality of life and costs after 1 year. Conclusion This study will lead to definition of a more efficient routine follow-up schedule for patients with a PM, aiming to reduce time and energy while preserving the safety of pacing therapy and the prognosis of the patient. The study will ultimately provide evidence-based guidelines for PM follow-up including knowledge of the responsibilities of cardiologists, technicians, and representatives of PM manufacturers.

Background: Radiofrequency (1717) catheter ablation is highly effective with a low complication rate. However, lesions created by RF energy are irreversible, inhomogeneous, and therefore potentially proarrhythmic. Objectives: The aim of this study was to examine the magnitude and importance of long-term proarrhythmic effects of RF energy. Methods and Results: Between 1991 and 1995, 120 patients underwent RF ablation for atrioventricular nodal reentrant tachycardia (AVNRT). Patient data were collected by contacting patients and/or filling out a questionnaire, and medical files were screened for recurrent, documented arrhythmias, pharmacological treatment, and repeated EP study. Referring cardiologists were asked about recurrences of tachyarrhythmias. Fourteen patients (11%) were lost to follow-up. During a mean follow-up of 10 years, six patients died. Recurrences of AVNRT were not any more observed after 3 years after ablation. A total of 29 patients (24%) suffered from new arrhythmias, 6 from type 1 atria] flutter, 6 from atrial tachycardia, 9 from atrial fibrillation, and finally 16 from symptomatic premature atria] contractions (PACs), needing medical treatment or a combination of these arrhythmias. Nine patients underwent pacemaker implantation, 4 after developing procedural atrioventricular (AV) conduction disturbances, 2 after His ablation for permanent atria] fibrillation, 1 patient for sick sinus syndrome, and another 2 patients after developing late AV block, respectively, 7 and 9 years after ablation. Conclusion: During long-term follow-up after RF ablation for AVNRT, no AVNRT recurrences were observed, but 29 patients (24%) suffered from new arrhythmias or late AV block. This potential proarrhythmic effect of RF energy promotes the application of alternative energy sources for ablative therapies for cardiac arrhythmias.

The earliest available working document of the Netherlands Society of Cardiology, prepared in 1951 [1], declared that the objectives of our Society, which was founded in 1934, were ‘the promotion of the knowledge of cardiovascular diseases and the support of measures in the fight against these diseases, and secondly promotion of the professional interests of the members’. In the notarial articles of 1977 [2], these objectives remained unchanged, except for the one on supporting measures in the fight against cardiovascular diseases, which had disappeared. Thirty years later, our Society articles (2007) show that the objectives now have a wider horizon, namely the development of cardiology and vascular medicine, the promotion of quality of care and the economic and social benefits of the members. It is assumed that these three pillars of Society policy are and will be able to cope with the requirements and questions emerging in the changing conditions of our time and the next decades. Consider for example the implementation of ‘hospital office hours’ versus the former 24 h/7 day duties to reduce fatigue in physicians and residents [3], the growing female emancipation in medicine [4], and the expending influence of patient organisations, health authorities, insurance companies and specifically the media. These factors not only affect the Society as an institute and organisation but also the cardiology community defined as its individual members spread out over the country. Intense mutual understanding and interaction is needed from both the Society and the local cardiology community. At the occasion of the 80th birthday of our Society, I prefer to address two supportive topics for our Society because I would regret if our Society were to become a ‘bloodless’ organisation, comparable with the crumbling Dutch trade unions due to the disinterest of their members. In the area of development of cardiology and vascular medicine, our Society has reduced its steering role in creating facilities for cardiovascular presentations of Dutch origin at the bi-annual national congresses; these are clustered between professional business and quality of care discussions. It is taken for granted that our Society is not actively involved in complex cellular, experimental or human studies. The independent cardiology departments of universities, fighting for their impact factor, and large general hospitals are better equipped to embark alone or together with the Netherlands Heart Foundation, ICIN-Netherlands Heart Institute, or drug and device companies on this type of (multicentre) study. I doubt whether this policy promotes warm feelings from the members for our Society. For most of those working outside large cardiology centres, Dutch cardiology research is a no-go area. Because the Society manages several large national patient data registries for cardiology specialities [5], the opportunity exists to encourage ‘applied clinical studies’ with the accumulated data which, according to Chalmers et al., provides more impact on care than most experimental research [6]. The cardiology community would undoubtedly profit if members nationwide were to participate in this type of clinical study. The national Followpace study with 23 participating Dutch centres resulting in many insights towards modern long-term conventional cardiac pacing constitutes a nice example of a large and long clinical study based on cooperation and low costs [7]. Daily bedside and outpatient practice in conjunction with involvement in a clinical study strongly promotes the quality of patient care and collegial assessment, such as I experienced for years. Our Society can take the necessary initiatives for these studies. In the past three decades our Society has devoted major efforts to improving the professionalism of the cardiology community and thereby increasing the quality of care. The implementation of a national cardiology training program in the 1990s, the postgraduate educational CVOI programs and guidelines that almost completely cover cardiac care have equipped our Society to respond adequately to increasing demands from Dutch society in general. These achievements rely on the long-term contribution of many members and deserve applause. However, after several assessments of the quality of departments and thus of the offered care, I could conclude that not the skill and knowledge of physicians but rather the lack of daily communication most often underlies professional shortcomings. Individual positive attitudes to care and compassion with the patient are indispensable but cannot compensate for insufficient communication in the ward and office. The origin of the saying ‘who is my doctor in charge?’ cannot only be attributed to the obliged shortening of the working hours—which has, however, promoted female participation in cardiology—but also to inadequate patient counselling and too few discussions with colleagues in the local cardiology community. As our Society rightly strives to preserve the role of ‘chef’ of our cardiovascular care menu, communication with all members and other involved parties should be more focused, otherwise the organisation will be put at risk. In view of our increasingly individualised world, communication cannot escape from receiving more attention in the initial and postgraduate cardiology training. This cultural change can result in a better cooperation between our Cardiology Society and its members and our patients will profit from this development.

In this study we reviewed the history of the surgical treatment of atrial fibrillation (AF). Of the various types, the maze operation has become nowadays the most successful surgical treatment of AF with or without concomitant cardiac surgery. We report on our 10-year experience with conventional maze III surgery: 203 patients were operated on without in-hospital mortality and acceptable morbidity. Success defined as the freedom of AF and other supraventricular arrhythmias was 80.1% for the patients with lone AF and 64.5% for the patients with concomitant AF after a mean of 4 years after surgery. We conclude that despite the complexity of the maze III operation this approach remains the golden standard from which future surgical and other ablative treatments of AF will be derived.

Our current knowledge of the arrhythmic genesis of atrial fibrillation (AF) converges to the AF multiple wavelets concept of Moe and Allessie of the 1970s, which was further elaborated by many other investigators. Around 1990, spontaneous automaticity arising in muscular sleeves of pulmonary veins was documented by Haissaguerre and his rhythm experts of Bordeaux. Therefore, it made sense that after failed antiarrhythmic drug treatment to prevent or suppress AF, these concepts were translated into invasive therapy. Around 1985, cardiac surgeons Cox and Guiraudon were the first to eliminate the type of AF based on the multiple wavelets concept with different cut-and-sew approaches. Due to the large impact of surgery, catheter ablation to eliminate automaticity with pulmonary vein isolation and (gradually more) atrial ablation lines followed. The assumption that the percutaneous approach would be a promising, less aggressive alternative for surgery, however, evaporated due to the inferior long-term results compared with current minimal invasive surgery [1]. These disappointing results conceivably prompted many groups to explore additional measures for the eradication of AF, such as energy sources different from radiofrequency, ablation of the cardiac nervous ganglia and elimination of zones of slow or non-uniform conduction guided by voltage differences or fragmentation mapping of atrial tissue [2]. Fragmented atrial signals and low electrogram voltages are often recordable in AF [3] for example after repair of congenital heart disease and various AF types and manifestations [2]. Their documentation with modern automated signal analysis and 3D mapping raises questions such as their relation to the amount and depth of scarred tissue, stability during sinus rhythm (P wave characteristics) and/or other types of AF and/or atrial tachycardia. Most crucial for therapeutic application is their reproducible contribution to the onset and perpetuation of AF with critical conduction pathways. Studies showed that the incidence and duration of fragmentation are larger in ‘chronic’ compared with ‘paroxysmal’ AF patients and are also related to ageing, left atrial dilatation, shorter excitable periods and non-uniform conduction or anisotropy in atrial tissue. Non-uniform conduction is caused by fibrosis and observed at higher ages and increased atrial pressure. Evidence also exists that mapping of fragmented P waves in sinus rhythm also points to patients prone to or known to have atrial tachyarrhythmias, reflecting functional or structural changes. These observations strongly suggest that fragmentation can potentially guide the ablation procedure in drug refractory AF. In this issue, De Vries et al. [4]. report on a comparative study of RF catheter ablation with pulmonary vein isolation and left atrial lines with or without additional ablative ‘shaving’ of atrial sites with fragmented signals in patients with chronic AF, the so-called defragmentation method. Because this approach takes more time and burning, it is not surprising that more (minor) complications occurred in the defragmentation group. However, it is unclear why defragmentation could not bring out a better result in terms of suppression of AF at 3, 6 and 12 months after the procedure. The report by De Vries et al. [4]. cannot be compared with the results of previous studies, because the applied method of additional defragmentation has not been carried out before. The authors attributed the lack of increased success to resumed conduction from the automatic foci in the pulmonary veins or through the atrial ablation lines, despite all procedural measurements of (successful) conduction block. Furthermore they discussed the risk of ‘insufficient defragmentation’, an ill-defined term, and speculated whether more defragmentation would have ameliorated the outcome. Unfortunately, the authors did not correlate the findings of atrial mapping with the number of recurrences of AF. Finally, weighting the 12-month AF outcome versus complication rate and prolonged procedural time, they concluded that defragmentation should not be considered a routine part of catheter ablation for AF. It should be emphasised that this advice results from a retrospective study of two Dutch invasive arrhythmia groups that undermines the power of this advice. Second, because defragmentation is guided by analysis of endocardial atrial signals, information about the epicardial conduction is missing. Simultaneous endocardial and epicardial recordings of atrial arrhythmias in the dog heart showed a clear discordant activation. Another study in the goat showed that this dissociation is related to an increase in separation between the epicardial layer and endocardial bundles and it is suggested that the thin epicardial layer of the atrial wall can conduct fibrillatory waves [5]. This layer is probably not (always) reachable or too risky with current ablative techniques. Third, our knowledge of the degree of structural and functional temporo/spatial differences of (slow) conduction or block and its relation to the ‘severity’ of AF is limited. More experimental work is necessary to understand the significance of fragmented signals in the individual patient at a certain time of the AF disease. Therefore, before classifying defragmentation a bridge too far, more investigations are needed. We learn little from success but more from failures, reason to thank the authors and the Journal for publication of this initially unsuccessful therapeutic method. The investigators are encouraged to contact the experimental lab to study fragmented atrial signals and to consider a prospective, well-defined, study in a comparable group of AF patients after they have gained more insight into the role of these fragmented atrial signals.

We developed a procedure that is able to detect, quantify and localize late potentials that will also be applicable to patients with abnormally wide QRS complexes.

The annual absolute number of cardiovascular implantable devices (CIEDs) is steadily increasing and is expected to rise even further, mostly due to the ageing demographic changes. [1] Consequently this will have a major impact on the post-implantation follow-up of monitor device function and patient condition both in terms of time and personnel. In a recent survey in 14 European countries remote monitoring (RM) was used in about 85% of all centres and the responding centres estimated that this percentage will increase to 93% by 2015. [2] In the same survey, guidelines and/or recommendations for the use of RM available from national scientific societies were reported to be totally absent in 93%. This lack of structural guidelines and/or recommendations will undoubtedly lead to a wide heterogeneity among centres using RM for the optimal care of patients after implantation. In addition responsibility related to remote follow-up is not clearly defined and leaves the device specialist and allied professionals in doubt with respect to the legal issues of RM. In 2009 the Netherlands Heart Rhythm Association (NHRA) took the initiative to develop a consensus document for RM in order to make a more uniform approach for RM and remote follow-up of the device patient. Close to 60 individuals have contributed to this expert consensus report. All aspects related to RM were divided into subgroups focussing on well-defined issues. The following subgroups were defined: Description of remote CIED monitoring Indications, benefits and limitations of remote CIED monitoring Patient perception of remote CIED monitoring Contribution of manufacturer to remote CIED monitoring Costs and reimbursement of remote CIED monitoring Preliminary recommendations for remote CIED monitoring For each subgroup a working group was formed. For each working group a chairperson was appointed and 5 to 8 members were carefully selected based on personal experience and individual expertise in the field. During half-day sessions working groups focussed on their specific subject which resulted in a concept document which was subsequently distributed by the chairperson for additional review. All sessions were also attended by the first three authors of the final expert consensus documents (CdC, JE and NvH) for process surveillance without interference with the contents. Finally the concept consensus report was reviewed during half-day sessions with all chairpersons. Despite the fact that RM was introduced more than 10 years ago, guidelines are available in only 5% of European countries, although RM is already widely implemented in medical practice. [2] A uniform approach to patients with CIED permitting RM is essential for a safe and optimal treatment. Clear and standardised information to the patient is also needed for optimal transmissions. In the CONNECT trial up to 45% of all alerts were not transmitted simply because the setup of the system was inappropriate.[3] In the Dutch expert consensus document a brochure is presented with patient instructions and education emphasising the responsibilities of the patient with respect to RM. [4] In addition a minimal set of parameters and alerts has been defined which may impose early medical treatment and prevent appropriate and inappropriate shocks. [5] Furthermore the introduction of RM into a device clinic needs a tailored organisation with structured appointments on scheduled or unscheduled visits, reason and type of device reprogramming etc. Of interest, the present expert consensus document has made a clear statement that RM can and will not be capable to be used as a 24/7 emergency system. The Heart Rhythm Society/European Heart Rhythm Association expert consensus document on monitoring of CIEDs was published in 2008 and lacks a clear statement on 24/7 surveillance, which fuelled concern with respect to legal issues for alerts. Finally, reimbursement will be a key issue for a wide implementation of RM. For private insurance companies and national health services the major challenge is in demonstrating improved health care with no rise in health rise costs. [6] In 82% of the countries in Europe there is no reimbursement structure despite the fact that preliminary studies demonstrated the cost effectiveness of RM and a high patient acceptance and satisfaction. [7] More prospective studies are needed with health economic costs as one of the primary endpoints before RM will be standard of care for all patients after device implantation. [8, 9]

Background Tissue mass and structure are relevant for initiation and persistence of fibrillation. Modification of the right atrium during maze surgery may change the arrhythmogenic substrate of atrial fibrillation (AF). Methods and Results Epicardial mapping was performed in 9 patients undergoing unmodified maze III surgery for lone paroxysmal AF. Simultaneous recording of AF on the right and left. atrium was carried out with two spoon-electrodes each harbouring 64 terminals. Activation maps of AF were made to study AF wavelet organization. The recording position on right and left atria was outside the surgical field and remained unchanged before and after surgery. Before surgery, mean right and left fibrillatory intervals were 174 +/- 123 ms, and 175 +/- 26 ms, respectively, and did not differ. After completed right atrial surgery, these fibrillary intervals remained unchanged. Mean right and left atrial dispersion of refractoriness (expressed as the coefficient of variation) were 4.2 +/- 0.8 and 5.2 +/- 3.8 ms. Only right atrial dispersion of refractoriness increased significantly after right-sided surgery. Prior to surgery, activation patterns of the left atrium were more complex than that of the right atrium. The left activation patterns became less complex afterwards; the right atrial activation patterns did not change. Conclusion The right atrial modification of maze III surgery neither affects atrial refractoriness during human lone AF nor changes AF wavelet organization. Thus, right atrial surgery does not modify the arrhythmogenic substrate of AF. These findings may imply that maze surgery can be restricted to the left atrium. (C) 2003 The European Society of Cardiology. Published by Elsevier Science Ltd. All rights reserved.

Little information is available about short-term and none about long-term follow-up of cardiac rhythm after percutaneous mitral balloon valvotomy (PTMV).We studied the long-term course of the supraventricular rhythm in 137 consecutive patients with severe mitral stenosis, who underwent PTMV. The rhythm before PTMV was sinus rhythm (SR) in 55% and chronic AF in 45% of patients. The mean follow-up time was 3.7+/-2.5 years (n=126). In patients with SR before PTMV, SR persisted in 91% of patients at the end of follow-up. In patients with chronic AF before PTMV, 84% of these patients were still in chronic AF at the end of follow-up, spontaneous conversion to SR did not occur. In 12 of 14 patients (85%), selected for cardioversion, SR was achieved, by DC cardioversion (n=11) or by drugs alone (n=1). After 2 years this outcome persisted, but after 4 years only 38% remained in SR.Pre-procedural SR will persist following PTMV. However in patients with chronic AF PTMV is not associated with reversion to SR, suggesting that measures should be undertaken to restore sinus rhythm.

Body surface mapping (BSM) can be used to identify the site of earliest endocardial activation of ventricular tachycardias (VTs). The multielectrode QRS morphology during VT is determined by both the site of earliest activation and the subsequent spread of electrical activation through the ventricles. This study investigated the relationship between the site of earliest endocardial activation, endocardial spread of activation, and the morphology of the multielectrode surface map in patients with remote myocardial infarction. In 14 patients with VT late (8.2+/-5.2 years) after myocardial infarction, BSM and simultaneous left ventricular 64-site basket endocardial mapping was performed during a total of 17 monomorphic VTs. In addition, multisite pacing by sequential use of the 64 basket electrodes was performed in 9 patients. BSM and basket mapping revealed the same endocardial breakthrough sites in 8 (47%) of 17 VTs and 189 (59%) of 322 pacing sites; adjacent sites were found in 2 (12%) of 17 VTs and 36 (11%) of 322 pacing sites. Large zones of conduction block explained the mismatch in localization in 2 (12%) of 17 VTs and 52 (16%) of 322 pacing sites. Regional differences in endocardial electrogram amplitudes were found as a cause for dissimilarity in 3 (18%) of 17 VTs and 73 (23%) of 322 pacing sites. Multiple endocardial breakthrough sites were found in 1 (6%) of 17 VTs and 8 (2%) of 322 pacing sites Finally, an epicardial exit site was suggested in 3 (18%) of 17 VTs as an explanation for mismatch, as no early endocardial activity could be recorded. Zones of conduction block, regional differences in signal amplitude, and multiple endocardial breakthrough sites are frequent causes for mismatch between BSM and basket catheter activation mapping

For a long time, it was a matter of debate whether fast rate or ventricular irregularity during atrial fibrillation (AF) was primarily responsible for the perception of palpitations, development of cardiomyopathy, and system emboli from the fibrillating atria. Recent studies have shown that ventricular irregularity associated with AF and manifested by random QRS intervals that constitute the diagnostic clue in scalar electrocardiography, can elicit symptoms and cardiomyopathy regardless of the rate. 1,2 Reduction of ventricular irregularity in AF patients in addition to control of fast ventricular rates, therefore, appears sensible to reduce symptoms and minimize the risk of cardiomyopathy. The underlying mechanisms of ventricular irregularity are uncertain and include concealed conduction within the atrioventricular (AV) node secondary to decremental conduction or electrical modulation of AV nodal propagation or pacemaker activity in the AV node. 1 If rate control is preferred to rhythm control, suppression of AV conduction with pharmacologic treatment and ablation of the AV junction are nowadays the established methods according to guidelines. However, the side effects and non-compliance associated with drug treatment or pacemaker dependency after ablation with potentially unfavourable effects of long-term right ventricular apical pacing often undermine the effectiveness of these therapies. These disadvantages urge the search for other therapeutic modalities for a safe and easy reduction of ventricular irregularity in AF. In 1983, Wittkampf and De Jongste 3 showed that continuous pacing in the right ventricle reduced the irregularity of QRS intervals during AF; faster pacing rates produced even more regularity by elimination of a large proportion of longer QRS intervals observed during slower ventricular rates. This phenomenon of rate stabilization is attributed to suppression or delay in AV nodal conduction by retrograde penetration of ventricular stimuli. This concept was incorporated in rate smoothing pacing algorithms that indeed significantly reduced variability of successive QRS intervals in AF patients. Unfortunately, the application of this algorithm was associated with a concomitant increase in mean heart rate by 21‐29%. 3 This drawback limited the widespread use of rate smoothing algorithms in paced patients with paroxysmal or permanent AF. In 1997, we tested a new rate smoothing programme delivered by the former Vitatron company, that uses a dynamic average of successive sensed or paced heart rates as a reference point. 4 The pacing rate followed the average heart rate and started pacing when the average ventricular rate dropped by 2.5 bpm. In addition, the algorithm prevented the occurrence of sudden brady- or tachyarrhythmia by pacing at a decelerating or accelerating rate at 2 bpm. In the acute pacing study, we observed that variability of the RR intervals could be reduced by 73% while the heart rate during pacing did not increase significantly (2%) compared with the preceding period without pacing. 5 In the unpublished randomized, single-blinded cross-over trial of patients with permanent (n ¼ 91) and paroxysmal AF (n ¼ 93), we observed a significant reduction in the variance of RR intervals in both patients categories. 6 However, quality of life, measured

Aim In patients with and without a permanent pacemaker His bundle ablation was performed for symptomatic drug-refractory atrial fibrillation. This study was performed to examine the complications of temporary pacing in patients without an already implanted pacemaker. Methods and Results Between January 1996 and December 1998, 152 consecutive patients, both referred and our own (non-referred), underwent His bundle ablation for drug-refractory atrial fibrillation. Primary end-point complications were temporary lead dislodgement requiring immediate repositioning (1), severe arrhythmia (2), death (3) and persistent damage to an already implanted pacing system (4). Secondary end-points were malsensing and malpacing of the temporary lead, and blood vessel problems. Lead dislodgement of the temporary pacemaker occurred in three patients (2·9%), all of whom were in the referred group. Severe arrhythmia and death did not occur. Persistent damage of the already implanted pacing system was not observed. Secondary end-points occurred in 15·8% of the patients and were successfully managed by a conservative approach. Conclusion Permanent pacemaker implantation is recommended prior to His bundle ablation in order to avoid haemodynamic deterioration due to dislocation of the temporary pacemaker lead. RF current used for His bundle ablation caused no permanent damage to permanent pacing systems.

Left ventricular (LV) dysfunction can occur due to chronic right ventricular apical pacing. Upgrading of the pacemaker to biventricular pacing is an option to reverse LV dysfunction but reprogramming of the atrioventricular (AV) timing can also be favourable. In this case report we describe the effect of AV-time reprogramming in a patient with LV function deterioration that emerged two years after implantation of a dual chamber system for sick sinus syndrome. Echocardiographc studies demonstrated a tremendous improvement in LV function during two years follow-up whereas the percentage of right ventricular pacing diminished dramatically. Careful analysis of the cause of LV deterioration can avoid unnecessary upgrading to biventricular pacing. (Neth Heart J 2010;18:604-5.).

Recent studies have indicated that nomen were less likely to receive sophisticated pacemaker devices than men. These differences could not be fully explained by demographic and clinical variables. The purpose of the present study was to assess whether a gender related difference might exist in pacemaker mode selection in patients undergoing their first implantation in The Netherlands. Records of first implants (n = 39,217) collected from 1988 through 1997 covering 93'% of all implantations in The Netherlands. From this population 33,564 (85.6%) patients were included for final analysis. I We observed no significant sex differences in pacemaker selection in patients with atrioventricular conduction disorders and bundle branch block. In patients with sick sinus syndrome, only very old women (greater than or equal to 85 years) had more atrial systems implanted than men of similar age (6.5% vs 3.5%), whereas men received more double chamber pacemakers (12.3% vs 10.3%) (P = 0.002). However, the relative distribution of physiological versus nonphysiological pacemakers in this subgroup rr as similar for men and women. In patients with chronic atrial fibrillation/flutter associated with bradycardia, sex differences were only apparent in the age group of 75-85 years; women received more dual chamber pacemakers (8.8% vs 5.3%) whereas men received more single chamber ventricular pacemakers (94.2% vs 89.8%) (P = 0.0011). With increasing age, sex differences in pacemaker selection rt ere absent, but there n as a considerable drop in implantation rate of dual chamber systems. Our study showed no major sex differences in the selection of pacemaker devices. Physicians select pacemaker devices by age rather than gender, which might be a rational choice

Aims Although arrhythmia surgery and radiofrequency catheter ablation to cure atrioventricular nodal reentrant tachycardia differ in technical concept, the late results of both methods, in terms of elimination of the arrhythmogenic substrate and procedure-related new and different arrhythmias, have never been compared. This constituted the purpose of this prospective follow-up study. Methods and Results Between 1988 and 1992, 26 patients were surgically treated using perinodal dissection or ‘skeletonization’, and from 1991 up to 1995, 120 patients underwent radiofrequency modification of the atrio-ventricular node for atrioventricular nodal reentrant tachycardia. The acute success rates of surgery and radiofrequency catheter ablation were 96% and 92%, respectively. Late recurrence rate in the surgical and radiofrequency catheter ablation groups was 12% and 17%, respectively. Mean follow-up was 53 months in the surgical group and 28 months in the radiofrequency catheter ablation group. The final success rate after repeat intervention was 100% in the surgical group and 98% in the radiofrequency catheter ablation group. Comparison of the initial and recent series of radiofrequency catheter ablated patients showed an increased initial success rate with fewer applications. In the radiofrequency catheter ablation group, a second- or third-degree block developed in three patients (2%), requiring permanent pacing, whereas in the surgical group no complete atrioventricular block was observed. Inappropriate sinus tachycardia needing drug treatment was observed in 13 patients (11%), mostly after fast pathway ablation, but was never observed after surgery. New and different supraventricular tachyarrhythmias arose in 27% of the patients in the surgical group and in 11% of the radiofrequency catheter ablation group, but did not clearly differ. Conclusion This one-institutional follow-up study demonstrated comparable initial and late success rates as well as incidence of new and different supraventricular arrhythmias following arrhythmia surgery and radiofrequency catheter ablation for atrioventricular nodal reentrant tachycardia. Today radiofrequency catheter ablation has replaced arrhythmia surgery for various reasons, but the late arrhythmic side-effects warrant refinement of technique.

In this issue of the Netherlands Heart Journal, the results of a substudy of the PREVEND trial are published.1 This prospective registry of presumably healthy citizens of Groningen aims to establish the association between microalbuminuria and the emergence of renal and cardiovascular diseases.2 This general population based long-term study extends the series of previous large-scale epidemiological trials conducted in the Netherlands. We recall among them the 1970 Vlagtwedde study for epidemiological cardiology and ischaemic heart disease, the 1982 Zutphen study of diet and cardiovascular diseases, the 1997 Maastricht study of circulatory arrest and sudden death, the 1998 Amsterdam study of out-of-hospital cardiac arrest and the 1999 Rotterdam study of prolonged QT interval and mortality.

After the introduction of temporary transcutaneous cardiac pacing by Paul Zoll in 1952, and of the temporary endocardial approach by Seymour Furman in the USA in 1958, the first definitive electronic pacemaker was implanted by Senning and Elmqvist in Sweden on 8 October 1958 using a thoracotomy to suture two epicardial electrodes. Actually, the ‘definitive’ unit placed in the abdominal wall of the pacemaker recipient, Arne Larsson, fired for only three hours. The first replacement, done the following morning, was followed by more than 22 units and numerous surgical interventions until Mr Larsson died in 2001.

Background —The morphology and polarity of the P wave on 12-lead ECG are of limited clinical value in localizing ectopic atrial rhythms. It was the aim of this study to assess the spatial resolution of body surface P-wave integral mapping in identifying the site of origin of ectopic right atrial (RA) impulse formation in patients without structural atrial disease. Methods and Results —Sixty-two–lead ECG recordings were obtained during RA pacing at 86 distinct endocardial sites in nine patients with normal biatrial anatomy. After P-wave integral maps were generated for each paced activation sequence, 17 groups with nearly identical map features were visually selected, and a mean P-wave integral map was computed for each group. Supportive statistical analysis to corroborate qualitative group selection was performed by assessment of (1) intragroup pattern uniformity by use of jackknife correlation coefficient analysis of the integral maps contained in each group and (2) intergroup pattern variability by use of the calculation of cross correlations between the 17 mean integral maps. The spatial resolution of paced P-wave body surface mapping in the right atrium was obtained by estimating the area size of endocardial segments with nearly identical P-wave integral maps by use of a biplane fluoroscopic method to compute the three-dimensional position of each pacing site. The latter approach yielded a mean endocardial segment size of 3.5±2.9 cm 2 (range, 0.79 to 10.75 cm 2 ). Conclusions —Use of the P-wave morphology on the 62-lead surface ECG in patients with normal biatrial anatomy allows separation of the origin of ectopic RA impulse formation into one of 17 different endocardial segments with an approximated area size of 3.5 cm 2 . This database of paced P-wave integral maps provides a versatile clinical tool to perform detailed noninvasive localization of right-sided atrial tachycardia before radiofrequency catheter ablation.

Background It is still unknown whether a fast heart rate or an irregular ventricular response in atrial fibrillation causes tachycardiomyopathy. Reduction in the variability of RR intervals without an increase in heart rate might be an alternative treatment when antiarrhythmic drugs fail to control the irregularity accompanying atrial fibrillation. Subjects and methods Eight patients underwent temporary right ventricular pacing, using a novel rate-smoothing algorithm prior to DC cardioversion or His bundle ablation. A rate-smoothing algorithm was utilized by right ventricular apical stimulation. Spontaneous and paced RR intervals during atrial fibrillation were quantified and processed for statistical analysis. Results The rate-smoothing algorithm resulted in a substantial reduction in the variance of the RR intervals (slow mode 73·1%, fast mode 40·0%) and RR range (slow mode 49·3%, fast mode 34·3%). In contrast to previous algorithms, the mean heart rate during pacing intervention in atrial fibrillation did not change significantly to the heart rate directly preceding the pacemaker intervention (+2%). Conclusions This initial study of the novel rate-smoothing algorithm shows that pacing intervention is a relatively safe, rapid and reliable alternative therapy for controlling irregular ventricular rhythms due to atrial fibrillation. Incorporation of the algorithm in implantable pacemakers appears justified, but demands further prospective studies in patients to evaluate relief of symptoms and reduction of tachycardiomyopathy due to atrial fibrillation.