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Introduction Dual-coil leads (DC-leads) were the standard of choice since the first nonthoracotomy implantable cardioverter/defibrillator (ICD). We used contemporary data to determine if DC-leads offer any advantage over single-coil leads (SC-leads), in terms of defibrillation efficacy, safety, clinical outcome, and complication rates. Methods and results In the Shockless IMPLant Evaluation study, 2500 patients received a first implanted ICD and were randomized to implantation with or without defibrillation testing. Two thousand and four hundred seventy-five patients received SC-coil or DC-coil leads (SC-leads in 1025/2475 patients; 41.4%). In patients who underwent defibrillation testing (n = 1204), patients with both lead types were equally likely to achieve an adequate defibrillation safety margin (88.8% vs 91.2%; P = 0.16). There was no overall effect of lead type on the primary study endpoint of "failed appropriate shock or arrhythmic death" (adjusted HR 1.18; 95% CI, 0.86-1.62; P = 0.300), and on all-cause mortality (SC-leads: 5.34%/year; DC-leads: 5.48%/year; adjusted HR 1.16; 95% CI, 0.94-1.43; P = 0.168). However, among patients without prior heart failure (HF), and SC-leads had a significantly higher risk of failed appropriate shock or arrhythmic death (adjusted HR 7.02; 95% CI, 2.41-20.5). There were no differences in complication rates. Conclusion In this nonrandomized evaluation, there was no overall difference in defibrillation efficacy, safety, outcome, and complication rates between SC-leads and DC-leads. However, DC-leads were associated with a reduction in the composite of failed appropriate shock or arrhythmic death in the subgroup of non-HF patients. Considering riskier future lead extraction with DC-leads, SC-leads appears to be preferable in the majority of patients.

Aims Cardiac Contractility Modulation (CCM) is a treatment for heart failure based on electrical signals applied during the absolute refractory period. CCM improves myocardial molecular and biochemical characteristics of heart failure and improves exercise tolerance and quality of life. However, the long term impact on survival has not been described. Methods and results Survival was determined retrospectively from a cohort of 68 consecutive heart failure cases with NYHA II or III symptoms and QRS duration ≤130ms, implanted with a CCM device between May 2002 and July 2013 in either Bochum or Ludenscheid, Germany. Results were compared with predicted survival (Seattle Heart Failure Model; SHFM) pre-implant for each patient. Mean follow-up was 4.5years (range 0.25–10.3years). Baseline characteristics were as follows: mean age 61years, 88% male, 68% with ischemic heart disease, 78% with an ICD, mean NYHA class 2.9±0.3, LVEF 26%±6% (range 15–40%) and mean QRS duration 106±11ms. Mortality rates (Kaplan–Meier analysis) at 1-, 2- and 5-years were lower with CCM than predicted by SHFM for the cohort (0% with CCM vs. 6.1% per SHFM, 3.5% vs. 11.8%, and 14.2% vs. 27.7%, respectively, p=0.007). Conclusions Long-term mortality rates in heart failure patients with NYHA (II–III) and QRS≤130ms are lower when treated by CCM than predicted for the cohort. These findings warrant substantiation in a prospective study.

Background A significant proportion of patients receiving CRT are non-responders. We evaluated the efficacy of Cardiac Contractility Modulation in subjects with reduced LVEF who, despite cardiac resynchronization therapy (CRT), continued to experience clinically significant symptoms. Methods This was a multi-center, open label, treatment-only, feasibility study of 17 CRT non-responders who received CCM therapy. Changes in NYHA class, ejection fraction (EF), Minnesota Living with Heart Failure Questionnaire (MLWHFQ) score, and exercise tolerance (6 minute walk test; 6MWT and peak VO2) were analyzed over 6 months. Mortality and hospitalization rates were determined. Results Patients (82% male) were 69.4 ± 9.6 years of age with baseline EF = 22.8 ± 6.5%. Among primary endpoints, peak VO2 increased 1.1 ± 1.6 ml/kg/min (p = 0.03) and MLWHFQ improved (−16 ± 16 points; p Conclusions Patients with heart failure and reduced ejection fraction who remain moderately to severely symptomatic despite use of CRT, may benefit from CCM therapy with improvement in quality of life and exercise tolerance. A larger prospective study in this population is warranted.

Cardiac contractility modulation (CCM) is an electrical stimulation treatment for symptomatic heart failure (HF) patients. The procedure involves implantation of two ventricular leads for delivery of CCM impulses. The purpose of this study is to compare the efficacy and safety of CCM when the signal is delivered through one vs. two ventricular leads.This prospective blinded randomized trial enrolled 48 patients. Eligible subjects had symptoms despite optimal HF medications, left ventricular ejection fraction40% and peakVOFollowing 6 months, similar and significant (p0.05) improvements from baseline in NYHA (-0.7±0.5 vs. -0.9±0.7) and MLWHFQ (-14±20 vs. -16±22) were observed in Group A and in Group B. PeakVOThe efficacy and safety of CCM in this study were similar when the signal was delivered through either one or two ventricular leads. These results support the potential use of a single ventricular lead for delivery of CCM.

Electrical storm (ES) is defined as the occurrence of ≥ three distinct episodes of ventricular arrhythmia (VA) in patients with implanted defibrillators within 24 h. Whereas conventional strategies for acute rhythm stabilization may be effective in some patients the occurrence of ES impairs survival and predicts recurrent VA. Catheter ablation in the setting of ES is complex and involves decisive strategies for individualized ablation approaches adapted to the patient's cardiac abnormalities. Success rates have been documented to be between 79 and 94% in larger studies and effective ablation improves survival and freedom from any VA. Ablation should be considered early in the treatment plan and availability may be improved by interhospital collaboration with highly experienced VA intervention centers.

An electrical storm (ES) is defined as multiple ventricular arrhythmia episodes leading to implantable cardioverter defibrillator interventions. Although conventional rhythm stabilization might be of help acutely, ES involves high mortality and morbidity. We evaluated the effect of catheter ablation strategies in the setting of an interhospital collaborative network on the recurrence of ventricular arrhythmia episodes and mortality in patients with ES. Consecutive patients presenting for invasive treatment of ES from December 2007 to December 2009 were included. All patients underwent catheter ablation of ventricular arrhythmia. The strategies were adapted to the individual cardiac pathologic features. The follow-up examination constituted periodic implantable cardioverter defibrillator interrogation. A total of 32 patients were included. Of the 32 patients, 29 (91%) had monomorphic ventricular tachycardia and 3 ventricular fibrillation. The mean number of implantable cardioverter defibrillator-treated episodes within 7 days before ablation was 16 ± 11. Of the 32 patients, 27 underwent ablation within 24 hours after admission, and 5 underwent acute ablation within 8 hours. In 3 patients, epicardial ablation was performed. In all but 2 patients (6%), the clinical arrhythmia was successfully ablated. During a median follow-up of 15 months, 10 patients (31%) had recurrences of sustained ventricular arrhythmia, including 2 patients (6%) with recurrent ES. Three patients (9%) died during the follow-up period. In conclusion, catheter ablation effectively suppressed ventricular arrhythmia midterm recurrences in patients presenting with ES. Catheter ablation is complex in these severely sick patients. The recurrence rate of ventricular arrhythmia appears to be 31% and the mortality rate to be 9%. Collaborative hospital networks to increase the prompt availability of ES ablation might help to optimize the ES outcome.

The ablation of ventricular tachycardia (VT) can be achieved using anatomically guided approaches using differentiated mapping and ablation techniques. The aim of this study was to evaluate the efficacy of limited linear ablation in the VT exit region identified during sinus rhythm mapping alone. One hundred fifteen consecutive patients presenting for ablation of post-myocardial infarction VT were included. After induction of the target VT during invasive electrophysiology, left ventricular substrate mapping during sinus rhythm to identify scar and border zone on the basis of endocardial bipolar voltage was performed. The exit site of the target VT was regionalized by a simplified vector pace mapping approach and targeted using limited linear ablation within the scar border zone. Seventy-seven percent of all inducible VT was successfully ablated. In 71 patients (62%), no sustained VT was inducible at the end of ablation procedure (complete success). During a median follow-up period of 16 + or - 10 months, 89 patients (77%) had no documented sustained ventricular arrhythmia. Seven patients (2%) had recurrences of the initially ablated VT, and 16 (14%) had new-onset VT. Patients with complete success had a significantly lower number of ventricular arrhythmia reoccurrences than patients with incomplete ablation success (11% vs 37%, p = 0.002). In conclusion, postinfarct VT was effectively ablated in 97% of patients without mapping during ongoing VT using a simplified regional linear ablation approach targeting the scar border zone. Freedom from any ventricular arrhythmia was achieved in 77% of patients during midterm follow-up.

Introduction: Short- and medium-term sinus rhythm (SR) rates after intraoperative radiofrequency ablation to treat permanent atrial fibrillation (AF) are well documented. Is rhythm success stable during a long-term follow-up? Methods and Results: A total of 130 patients who had undergone intraoperative radiofrequency cooled-tip endocardial ablation (SICTRA) of permanent AF (mean AF duration 6±5 years) concomitant to open heart surgery more than 3 years ago were followed up using electrocardiogram (ECG), Holter-ECG, and echocardiography and compared with 12-month follow-up data. In 55% of patients, only the left atrium and in 45%, both atria were treated using SICTRA. Mitral valve replacement was performed in 21, mitral valve reconstruction in 25, aortic valve replacement in 13, CABG procedures in 51 (including 11 patients with additional mitral valve surgery), and complex procedures in 20 patients. Sixty-nine percent of patients (90/130) were in stable SR after a median period of 48 months, whereas 28% (36/130) were in AF and 3% (4/130) were in atrial flutter. In between the 12-month follow-up and the long-term follow-up, seven patients converted to AF after having documented SR, two patients converted to typical right atrial flutter after being in SR, and two patients from AF to left atrial macroreentry. After left and biatrial SICTRA, SR rates were comparable (73% vs 66%, P = 0.45). Echocardiography revealed 73% of patients in SR to have effective left atrial contraction. Conclusions: SICTRA restores long-term stable SR in 69% of all patients. Nine percent of patients reconverted back to atrial arrhythmia after having documented SR at 12 months.

AIMS We evaluated the feasibility of the TULIP (Threshold test using Upper Limit during ImPlantation) protocol, which was designed to provide a confirmed, low defibrillation energy value during implantable cardioverter defibrillator (ICD) implantation with only two induced ventricular fibrillation (VF) episodes. METHODS AND RESULTS Ninety-eight patients (62 +/- 12 years, 86 male) from 13 clinical centres underwent an active can ICD implantation. A single coupling interval derived from electrocardiogram lead II during ventricular pacing was used for VF induction shocks at 13, 11, 9, and 6 J in a step-down manner until the upper limit of VF induction (ULVI) was determined. If ULVI >or=9 J, a defibrillation energy of ULVI + 4 J was tested. For ULVI

Aims To demonstrate the safety and efficacy of saline irrigated cooled-tip atrial linear endocardial radiofrequency ablation (SICTRA) concomitant to open-heart surgical procedures in the treatment of permanent atrial fibrillation (AF). Methods and Results Two hundred and twenty-two patients presenting with permanent AF and the need for cardiac surgery were included. In addition to the cardio-surgical procedure [mitral valve (MV) surgery (n ¼ 94), aortic valve replacement (n ¼ 29), bypass surgery (n ¼ 76 including 24 patients with additional MV surgery), and combined procedures (n ¼ 23)] concomitant SICTRA was performed. In 116 patients, the ablation pattern was restricted to the left atrium alone. During the mean follow-up of 29 months, 174 patients (78%) converted to sinusrhythm (SR). In patients with SICTRA restricted to the left atrium conversion rates were not different compared to a biatrial approach (83 vs. 74%, P ¼ 0.47). Thirty-days mortality was found to be 4% (9/222). Post-mortem evaluation revealed 23% of all lesions to be histologically non-transmural. In the overall group, only 4% of patients developed sustained secondary regular atrial arrhythmia. Conclusions SICTRA safely and effectively restores stable SR in 78% of patients with permanent AF undergoing open-heart surgery. Rhythm outcome is not influenced by treatment of the right atrium. Sustained regular atrial arrhythmia with the need for invasive treatment strategies occurs in 4% although intra-operative ablation lesions are often non-transmural.

UNLABELLED Ablation of Atrial Tachycardia after Antiatrial Fibrillation Surgery. INTRODUCTION Surgical treatment of atrial fibrillation (AF) is gaining widespread acceptance. However, therapeutic modalities for secondary regular atrial tachycardia are still empiric. METHODS AND RESULTS After linear atrial cooled-tip radiofrequency ablation (SICTRA) during cardio-surgical procedures to cure permanent AF, patients with regular atrial tachycardia were identified. Invasive electrophysiology including electroanatomic mapping was performed. Catheter ablation was directed to suppress atrial arrhythmia depending on activation mapping findings. Follow-up was performed after 3 months and then after every 6 months. Of 238 patients, 12 (5.0%) were identified with regular secondary arrhythmias (12 +/- 7 months after surgery) including 9 (3.8%) with persistent forms originating from the right atrium (RA) in six (66%) (isthmus-dependent macroreentry in 4, incisional macroreentry in 1, and RA ectopy in 1). All patients with RA origin of the tachycardia were successfully ablated. Two patients had left atrial (LA)-macroreentry circling around the mitral valve indicating insufficiency of the intraoperative ablation procedure: one patient was successfully ablated within the LA isthmus, in the other patient no complete conduction block could be induced. One patient had LA-macroreentry degenerating into AF, and ablation was not performed. During follow-up (9 +/- 4 months), no recurrences of atrial tachycardias were documented after successful ablation. CONCLUSIONS Persistent regular "secondary" arrhythmia occurred in 3.8% (9/238) of patients after SICTRA to treat permanent AF. Predominantly (67%; 6/9), the arrhythmia was located in the RA mostly incorporating the RA-isthmus. Catheter ablation was highly effective for RA tachycardia (100%). In three cases (33%), LA-macroreentry was documented and catheter ablation was successful in only one patient (overall success 78%).

Introduction: Catheter ablation of ventricular tachycardia (VT) in remote myocardial infarction (MI) often requires excessive mapping procedures. Documentation of the electrical substrate via electrogram amplitude may help to identify regions of altered myocardium resembling exit areas of reentrant VTs. Methods and Results: A patient with multiple symptomatic monomorphic VTs (biventricular ICD, remote MI) underwent electroanatomic substrate mapping (CARTO™) for VT ablation. Regions of scar (bipolar electrogram amplitudes ≤0.5 mV), normal myocardium (≥1.5 mV), and “altered” myocardium (0.5–1.5 mV) were identified. Ablation was directed to regions with “altered” myocardium based on pace map correlation. After ablation the clinical VT did not reoccur. The patient died due to worsening of heart failure 7 days afterward. During postmortal evaluation specified sites of electroanatomic mapping were correlated to histopathological findings. Annotated scar areas were documented to consist of areas with massive fibrosis (≥80% of mural composition). Ablations were found to span through regions with intermediate fibrosis (21–79%) mapped as “altered” myocardium. Ablation produced transmural coagulation necrosis of mesh-like fibrotic tissue with interspersed remnants of myocardial cells up to a maximum depth of 7.0 mm. Subendocardial intramural bleedings were universal findings 7 days after ablation. Conclusions: Electroanatomic substrate mapping for VT ablation sufficiently identified regions of scar and normal myocardium. Regions with bipolar electrogram amplitudes between 0.5 and 1.5 mV were found to correlate to areas of “intermediate” fibrosis (21–79%) with only remnant strands of myocardial cells and were identified as target region for ablation. Cooled-tip endocardial radiofrequency ablation lead to transmural coagulation necrosis up to a depth of 7.0 mm.

Cardiac resynchronization therapy (CRT) devices not only deliver effective treatment but may also serve as valuable diagnostic tools in heart failure management. In the present study, the minutes of daily physical activity and heart rate variability, measured by sensors incorporated into such a device, reflected the effects of CRT and were related to New York Heart Association functional class.

Background Coronary angiographies performed during acute coronary syndrome show different coronary morphologies—vessel occlusions, thrombi and various types of stenoses. In a few cases of acute coronary syndrome, angiography reveals normal coronary arteries. It is the purpose of this study to analyze this specific subset of patients who presented with an acute coronary syndrome but had a normal coronary angiogram with respect to the preangiographic diagnostics, risk stratification and clinical follow-up. Methods and results A total of 897 coronary angiographies were performed as an emergency procedure in our institution. The majority of patients ( n =821) presented with coronary artery disease and the majority was treated by mechanical revascularization (86.3%). In 76 patients (8.5%), no coronary artery stenosis was documented. However, according to the preangiographic risk stratification, coronary artery disease was expected in these patients. Observations documented angiographically included coronary spasms (6.6%) and muscle bridges (5.3%). During a mean follow-up of 11.2±6.4 months, one patient developed an acute myocardial infarction requiring coronary intervention. All other patients were free of any cardiac event. Conclusions In summary, we have to consider that coronary angiography may not always detect the cause of myocardial ischemia in every patient. There is a small group of patients with normal coronary angiograms during acute coronary syndrome. Additional diagnostic procedures like intravascular ultrasound (IVUS) or the assessment of intracoronary physiological parameters may increase the diagnostic value of angiography.

Aggressive antithrombotic medical therapy may increase the rate of access-site complications after percutaneous coronary intervention. Frequently, emergency coronary interventions have to be performed in a situation when thrombolysis therapy was administered as the first-line therapeutic approach in acute myocardial infarction but failed to achieve stable conditions. We analyzed the rate of femoral bleeding complications after emergency coronary intervention in 76 consecutive patients with unsuccessful thrombolysis in acute myocardial infarction. All invasive procedures were performed in a time period no longer than eight hours after thrombolysis was administered. Additional antithrombotic therapy with heparin and glycoprotein IIb/IIIa-inhibitors was given during intervention in 100% and 38.2% of patients, respectively. In three patients (3.9%) femoral hematomas without therapeutic consequences were documented; one patient (1.3%) developed a hematoma requiring blood transfusion. A pseudoaneurysm, fistula or surgical vascular intervention did not occur. Coronary interventional procedures in rescue situations can be performed with excellent safety with respect to access-site bleeding complications even under conditions of ongoing thrombolysis therapy and aggressive antithrombotic medical regimens.

This study was undertaken to evaluate if a history of episodes of atrial fibrillation (AF) has an effect on survival in patients (pts) with implanted cardioverter defibrillators (ICD).Retrospective analysis of baseline characteristics, medication and endpoints in pts receiving a dual-chamber ICD comparing pts without (group 1: n = 291) and with a history of AF (group 2: n = 68). Pts in groups 1 and 2 did not differ with regard to baseline characteristics. Forty-one pts (8.7%) experienced a detected episode of AF. During the study period (mean follow-up 9.5 months) 25 pts died (5.8% of group 1 vs 11.8% of group 2). Patient survival was found to be 97.9% vs 91.2% ( n = 279 vs 63) at 3 months after implantation, 97.5% vs 89.7% ( n = 244 vs 54) at 6 months, and 93.7% vs 86.5% ( n = 96 vs 28) at 12 months in group 1 vs group 2 (p = 0.005). The risk of death increased after a first episode of AF was experienced during follow-up (RR = 5.0, p = 0.0007). Independent predictors of mortality are NYHA class (p = 0.002, history of AF (p = 0.009 for predicting early mortality), and detected episodes of AF during follow-up (p = 0.001).ICD-patients with a history of AF had a higher than average risk of death early after implantation and after device-detected episodes of AF.

The clinical significance of myocardial contusion (MC) following blunt thoracic trauma is still unknown. Accordingly, in this prospective study in a regional trauma center we investigated the acute and long-term clinical significance of MC.One-hundred eighteen patients with manifest or suspected blunt thoracic trauma were evaluated for cardiac injury. Initial assessment was based on results of electrocardiographic, echocardiographic, and serial enzyme measurements. A follow-up (FU) assessment conducted at 3 and 12 months, respectively, was performed using electrocardiography, echocardiography, and a bicycle ergometry exercise test.Of the 118 patients in the total sample, 67 (56.8%) required admission to the surgical intensive care unit (SICU) because of the severity of their noncardiac injuries. Fourteen patients of the total sample (11.8%) were diagnosed with MC and 13 of these (92.9%) belonged to the intensive care admissions, thus representing an incidence of 19.4% in this patient group. During the hospitalization period none of the patients with MC experienced acute cardiac complications. Eighty-six patients (72.0%) were assessed at FU. No new pathologies were found except in one patient. Exercise testing revealed no ECG abnormalities and none of the patients experienced limitations on the bicycle ergometer due to a cardiac cause.The incidence of 19.7% of MC in our patients with blunt chest injury requiring intensive care treatment indicates that this condition is frequent in polytraumatized patients. Outcome and prognosis in patients with MC is favorable and, thus, routine cardiac work-up is not indicated. Specific diagnostic and therapeutic measures should be limited to cases where cardiac complications develop.

Implantable defibrillators (ICD) are highly effective in reducing arrhythmia-related mortality. ICD shock therapy has been shown to increase psychological distress, health care utilization, and is associated with increased mortality. The Protecta ICDs (Medtronic Inc., Minneapolis, MN, USA) have algorithms designed to reduce unnecessary and inappropriate shock therapy.The PainFree SmartShock™ Technology (PainFree SST) study is a prospective, multicenter, clinical trial with two consecutive phases, a premarket phase safety study and a postmarket phase effectiveness study. We report the results of the PainFree SST safety study. The premarket phase aimed to investigate safety in the first year postimplant, and to determine if the novel algorithms (T-wave discrimination, right ventricular lead noise discrimination and confirmation+) affect appropriate ventricular fibrillation (VF) detection. Patients (total: n = 246 [male 78%, mean age 63 year, primary prevention indication in 76%]) were implanted either with a Protecta XT dual-chamber ICD (n = 114 [46%]) or a defibrillator with cardiac resynchronization therapy (n = 132 [54%]). Appropriate VF detection was measured during VF induction at implantation when the novel algorithms were programmed ON. A two-second delay in VF detection was classified as clinically significant. No delay in VF detection was observed with all algorithms programmed ON. No unanticipated serious adverse device effects occurred during first year postimplant.The results of the premarket phase of the PainFree SST trial demonstrate the safety of the Protecta XT defibrillators. Detection of induced VF was not delayed with SmartShock™ algorithms ON.

Implantable cardioverter–defibrillators (ICD) reduce mortality in patients with severely impaired left ventricular function. In randomized studies, female patients are underrepresented and data on ICD therapy is limited. Atrial fibrillation (AF) is a determinant of poor prognosis but has not been consistently evaluated. We evaluated the risk factors for the occurrence of ventricular arrhythmia episodes in patients with primary ICD prophylaxis. Consecutive patients after ICD implantation for primary prophylaxis were followed. During follow-up, detected sustained episodes of ventricular arrhythmia were documented. Multivariate analysis controlled for propensity score was used to evaluate the correlation between gender, history of AF, and the occurrence of ventricular arrhythmia episodes. A total of 400 patients (19.8% female; n = 79) were included. During follow-up, 64 patients (16%) had appropriate ICD therapy episodes. Men (18%) had significantly more often episodes than women (8%; p = 0.025). Patients with a history of AF (102, 25.5%) had significantly more often episodes (30%) compared to patients without a history of AF (11%; p

Background Atrial fibrillation (AF) is a multifactorial disease of the atria. Objective We studied the differences in the atrial autonomic innervation pattern in subjects with AF compared with sinus rhythm (SR). Methods Preparation of postmortem isolated hearts of subjects with documented persistent AF (group A) and SR (group B) included: (1) histological sectioning of predefined areas and quantification of nerve density, and (2) differentiation using immunohistochemistry in adrenergic (sympathetic, tyrosine-hydroxylase antibody), cholinergic (parasympathetic, choline-acetyltransferase antibody) and mixed (adrenergic and cholinergic staining) nerves. Results Characteristics of subjects in group A (N = 15) and group B (N = 24) did not differ. The mean overall nerve density was similar between groups (A: 0.31 ± 0.25/mm 2 ; B: 0.35 ± 0.25/mm 2 ; P = .87). Nerve density appeared higher in the region of the pulmonary vein ostia and antrum (group A: 0.38 ± 0.21/mm 2 ; group B: 0.32 ± 0.19/mm 2 ,) compared with other locations of the right and left atrium. A total of 2,224 (group A: 685; group B: 1539) nerves were differentiated using immunohistochemistry. There was a high degree of colocalization of adrenergic and cholinergic nerves (group A: 80% mixed staining, group B: 69% mixed staining). In group A hearts there was a significantly lower density of predominantly cholinergic nerves (0.025 ± 0.052/mm 2 vs. 0.058 ± 0.099/mm 2 ; P = .008) and a higher density of nerves containing adrenergic components (0.24 ± 0.18/mm 2 vs. 0.18 ± 0.17/mm 2 , P = .046). Conclusion Overall autonomic nerve density did not differ between atria with persistent AF compared with SR. On a morphological level, we detected a shift toward a lower density of cholinergic nerves and a higher density of nerves containing adrenergic components in AF subjects.

Transcatheter aortic valve implantation (TAVI) is an alternative therapy for symptomatic severe aortic valve stenosis in high-risk patients with several co-morbidities. We evaluated the 1-year effects of TAVI on quality of life, exercise capacity, neurohormonal activation, and myocardial hypertrophy. From June 2008 to October 2009, consecutive patients aged ≥75 years with symptomatic severe aortic valve stenosis (area1 cm(2)) and a logistic euroSCORE ≥15% or aged60 years with additional specified risk factors underwent TAVI. An aortic valve prosthesis (CoreValve) was inserted in a retrograde fashion. Examinations were performed before and 30 days and 1 year after TAVI. An assessment of the quality of life (Minnesota Living with Heart Failure Questionnaire), a 6-minute walking test, measurement of B-type natriuretic peptide, and echocardiography were performed. In 51 patients (mean age 78 ± 6.6 years, mean left ventricular ejection fraction 58.4 ± 12.2%), the follow-up examinations were performed after TAVI. The 1-year follow-up visit after TAVI revealed significantly improved quality of life (baseline Minnesota Living with Heart Failure Questionnaire score 39.6 ± 19 vs 26.1 ± 18, p0.001) and more distance covered in the 6-minute walking test (baseline 185 ± 106 vs 266 ± 118 m, p0.001). The B-type natriuretic peptide level had decreased (baseline 642 ± 634 vs 323 ± 266 pg/ml, p0.001), and the left ventricular mass index had decreased (156 ± 45 vs 130 ± 42 g/m(2), p0.001). The left ventricular diameter and ejection fraction remained unchanged. In conclusion, TAVI leads to significantly reduced neurohormonal activation, regression of myocardial hypertrophy, and lasting enhancement of quality of life and exercise capacity in patients with symptomatic and severe aortic stenosis 1 year after intervention.

Although a low-energy cardioversion (LEC) shock from an implantable cardioverter-defibrillator (ICD) can terminate ventricular tachycardia (VT), it frequently triggers ventricular fibrillation (VF) and is therefore not used in clinical practice. We tested whether a modified LEC shock with a very short duration (0.12-0.36 ms), termed "field stimulus," can terminate VT without triggering VF.In 13 sedated patients with implanted ICDs, we attempted to induce VT and to terminate the arrhythmias by field stimuli during hospital predischarge tests.In eight patients, 27 VT episodes were induced and treated with a total of 46 high-voltage (25-200 V) field stimuli, which terminated 11 VT episodes (41% efficacy) and never accelerated VT into VF. VT episodes slower than 230 beats per minute (bpm) (median rate) were terminated more successfully than faster arrhythmia episodes (69% vs 15%, P0.01). The strength of the field stimulus had no major influence on the effectiveness. We therefore postulate that suboptimal timing of field stimuli (delivered simultaneously with a sensed event in the right ventricular apex) was the main reason for failed VT terminations.A short (0.12-0.36 ms), high-voltage (50-100 V) field stimulus delivered from the shock coil of an implanted ICD system can safely terminate VT, especially for VT rates below 230 bpm. We believe that it would be reasonable to test the effectiveness of automatic field-stimulus therapy from implanted ICDs in VT episodes up to 230 bpm that are not susceptible to termination by antitachycardia pacing.

Aims We performed a randomized, double blind, crossover study of cardiac contractility modulation (CCM) signals in heart failure patients. Methods and results One hundred and sixty-four subjects with ejection fraction (EF) < 35% and NYHA Class II (24%) or III (76%) symptoms received a CCM pulse generator. Patients were randomly assigned to Group 1 ( n = 80, CCM treatment 3 months, sham treatment second 3 months) or Group 2 ( n = 84, sham treatment 3 months, CCM treatment second 3 months). The co-primary endpoints were changes in peak oxygen consumption (VO2,peak) and Minnesota Living with Heart Failure Questionnaire (MLWHFQ). Baseline EF (29.3 ± 6.7% vs. 29.8 ± 7.8%), VO2,peak (14.1 ± 3.0 vs. 13.6 ± 2.7 mL/kg/min), and MLWHFQ (38.9 ± 27.4 vs. 36.5 ± 27.1) were similar between the groups. VO2,peak increased similarly in both groups during the first 3 months (0.40 ± 3.0 vs. 0.37 ± 3.3 mL/kg/min, placebo effect). During the next 3 months, VO2,peak decreased in the group switched to sham (−0.86 ± 3.06 mL/kg/min) and increased in patients switched to active treatment (0.16 ± 2.50 mL/kg/min). MLWHFQ trended better with treatment (−12.06 ± 15.33 vs. −9.70 ± 16.71) during the first 3 months, increased during the second 3 months in the group switched to sham (+4.70 ± 16.57), and decreased further in patients switched to active treatment (−0.70 ± 15.13). A comparison of values at the end of active treatment periods vs. end of sham treatment periods indicates statistically significantly improved VO2,peak and MLWHFQ ( P = 0.03 for each parameter). Conclusion In patients with heart failure and left ventricular dysfunction, CCM signals appear safe; exercise tolerance and quality of life (MLWHFQ) were significantly better while patients were receiving active treatment with CCM for a 3-month period.

Decisions for coronary revascularisation are frequently based on visual assessment of the severity of a stenosis. In patients with intermediate left main stem lesions clinical decision making based on FFR is safe and feasible. This study was performed to assess the accuracy of visual angiographic assessment of intermediate or equivocal left main coronary artery (LMCA) stenoses by experienced interventional cardiologists when taking fractional flow reserve (FFR) measurements as the gold standard.Fifty-one patients with intermediate (40-80% diameter stenosis by angiography) or equivocal LMCA disease were evaluated by FFR. Angiograms were then reviewed by 4 experienced interventionalists from different university hospitals blinded to FFR results. Lesions were visually assessed and their significance classified as 'significant', 'not significant', or 'unsure' if the observer was unable to make a decision regarding lesion significance based on the angiogram.Results were compared with two different FFR cutoff values (0.75 andor = 0.80) for hemodynamic significance. The 4 reviewers achieved correct lesion classification in no more than approximately 50% of cases each, regardless of FFR threshold. The interobserver agreement between two reviewers in excess of the agreement expected due to chance was outperformed on average by only 16%. Furthermore, interobserver variability was large resulting in unanimously correct lesion classification in only 29% of all cases.The functional significance of intermediate and equivocal LMCA stenoses should not be based solely on angiographic assessment even by experienced interventional cardiologists.

Cardiac resynchronization therapy has been shown to be an effective treatment for patients with systolic ventricular dysfunction, prolonged (120 ms) QRS duration, and New York Heart Association (NYHA) functional class III or IV symptoms despite optimal medical therapy. However, studies show that a majority of heart failure patients have QRS duration120 ms. We have been investigating the potential utility of cardiac contractility modulating (CCM) signals as a treatment option for such patients. Cardiac contractility modulating signals are non-excitatory signals applied during the absolute refractory period using a pacemaker-like device that connects to the heart with pacemaker leads. Acute studies carried out in animals and humans with heart failure suggest that CCM signals can enhance the strength of left ventricular contraction. Results of initial long-term studies designed mainly to demonstrate feasibility and provide preliminary indication of safety in patients with medically refractory NYHA functional class III heart failure are summarized. The results of these preclinical and clinical studies formed the basis for proceeding with two prospective, randomized clinical studies currently underway to definitively test the safety and efficacy of this treatment.

The correct detection of atrial arrhythmias by pacemakers is often limited by the presence of far-field R waves (FFRWs) in the atrial electrogram. Digital signal processing (DSP) of intracardiac signals is assumed to provide improved discrimination between P waves and FFRWs when compared to current methods. For this purpose, 100 bipolar and unipolar intracardiac atrial recordings from 31 patients were collected during pacemaker replacement and used for the off-line application of a novel DSP algorithm. Digital processing of the atrial intracardiac electrogram (IEGM) signals (8 bit, 800 samples/s) included filtering and calculation of the maximum amplitude and slope of the detected events. The form parameter was calculated, being the sum of the most negative value of the amplitude and that of the slope of the detected event. The algorithm collects form parameter data of P waves and FFRWs and composes histograms of these data. A sufficiently large gap between the FFRW and P wave histograms allows discrimination of these two signals based on form parameters. Three independent observers reviewed the reliability of classification with this algorithm. Sensitivity and specificity of FFRW detection were 99.63% and 100%, respectively, and no P waves were falsely classified. It can be concluded that this novel DSP algorithm shows excellent discrimination of FFRWs under off-line conditions and justify the implementation of this algorithm in future pacemakers for real-time discrimination between P waves and FFRWs. This method prevents false mode switching and allows correct and immediate intervention pacing for atrial tachyarrhythmias.

To assess the practical application and safety of prehospital antithrombotic therapy with the glycoprotein (GP) IIb/IIIa inhibitor eptifibatide for patients with suspected acute coronary syndrome (ACS) or myocardial infarction (MI).Open-labeled pilot study. Patients with typical chest pain who were seen within 6 h of the onset of symptoms were enrolled in the mobile emergency ambulance. Patients were stratified by even/uneven days to receive standard treatment or standard treatment plus an IV bolus of eptifibatide (180 microg/kg body weight) followed by a continuous eptifibatide infusion (2 microg/kg/min). The main outcome measurement was a combination of prehospital or in-hospital death, reinfarction, revascularization of target vessels, and major bleeding complications.A total of 356 patients (age range, 29 to 75 years; women, 24.7%) were included in the analysis. On admission to the hospital, the diagnosis of ACS or MI was confirmed in approximately 60% of patients, and alternative diagnoses were made in 40% of patients. The rates of complications, including fatal and nonfatal complications occurring during transportation and during subsequent hospitalization, were similar in both study groups. The primary end point occurred in 11.8% of patients in the control group, and in 9.6% of those in the eptifibatide group (difference not significant).The prehospital administration of the GP IIb/IIIa inhibitor eptifibatide is feasible and safe in patients with clinically suspected ACS and MI. The benefit of this treatment has yet to be established in a large-scale multicenter study.

The treatment especially of frequent ischemic VT remains a challenge for medical and catheter ablation procedures. We evaluated the efficacy of a substrate-based procedure to eliminate clinical VTs in this patient collective.In 25 consecutive patients (ejection fraction 37+/-12%) with frequent symptomatic medically refractory ischemic VT (with recurrent ICD-shocks), left ventricular anatomic scar mapping (Biosense Webster CARTO) was performed in order to modify the underlying myocardial substrate. Scar tissue was identified as having bipolar voltages0.5 mV. Prior to the procedure an electrophysiological study (EPS) to determine number and morphology of inducible VTs was performed. Linear ablation procedures (8 mm tip, 70 Watts, 70 degrees C) were based on the findings of scar areas and proximity to anatomic obstacles. Correct location of ablation was documented by similarity of the morphology during pace-mapping. Follow-up included clinical evaluation, ICD holter interrogation plus holter ECG recording.The clinical VT was eliminated by linear catheter ablation in 23/25 patients (92%) (failure due to unstable catheter position during transaortic approach in 1 and epicardial origin of VT in 1). In 16/23 patients (70%) complete success could be produced with no VT inducible after substrate modification (1.7+/-1.0 lines per patient). In 7 patients (30%) only partial success was documented with further VTs inducible after ablation. No procedure-related complications occurred. During follow- up (10+/-4 months) 4 patients (16%) had occurrences of new VTs documented on ICD holter (3 patients with initially partial success and 1 with initial complete success) differing in cycle length and morphology from the clinical VT. Comparing patients with complete to those with partial success, there was a statistically significant difference of 93 vs. 48% freedom of arrhythmia (p=0.03). No difference in regard to baseline characteristics existed in these two patient subgroups.Ablation of frequent VTs in patients with ischemic cardiomyopathy can be safely performed using electro-anatomic scar mapping with a high procedural success of 90%. Based on the morphological findings, linear ablation can suppress inducibility of all VTs in 70% of patients with high mid-term efficacy. In patients with only partial ablation success, non-clinical VTs often occur early during follow-up (50%).

Aims Efficacy of pace-termination of atrial arrhythmias (ATP) may depend on atrial cycle length and regularity. Whether device programming of ATP therapies can improve ATP efficacy and alter atrial tachyarrhythmia burden is unknown. Methods and results ATP efficacy was evaluated in 61 patients (39 males; 66 10 years) with a standard indication for pacing, 95% with a history of AT/AF. Each patient was implanted with a novel DDDRP pacemaker capable of delivering ATP therapy. ATP efficacy and AT/AF frequency and burden were compared within each patient during a period of nominal ATP programming (NP) followed by a period of aggressive incremental programming (IP). Adjusted ATP-termination efficacy was higher during IP than during NP (54.8% vs 37.9%, P\0:05). No differences in AT/AF frequency (3.3 5.9 vs 3.2 6.9 day 1 )o r burden (18 28% vs 18 29%) were observed comparing NP with IP. The majority of episodes during both the NP (81%) and IP (77%) periods terminated within 10 min. Episodes lasting 24 h or more accounted for only 0.4% of the episodes in both groups, but accounted for 38% of the average burden during NP and 51% during IP. Conclusions Device programming of ATP therapies can influence the number of treated episodes and the efficacy of ATP therapies although arrhythmic frequency and burden may not change. Total atrial arrhythmia burden is disproportionately influenced by long ([24 h) episodes.

Many different stent types are available for intracoronary placement. No clinical trial has demonstrated clearly the superiority of any stent design over another.This study was designed to analyze clinical and angiographic results after using intracoronary PURA-VARIO (Devon Medical, Hamburg, Germany) (PUVA) stents. A total of 306 implanted stents were investigated in a series of 217 unselected patients (61.2 +/- 10.7 years, 74.3% male). Stenting was performed electively and during acute coronary syndromes. Stents were manually mounted on angioplasty balloons and expanded in the target lesion. Angiographic measurements were carried out by quantitative coronary angiography.Stenting was successful in 214/217 patients (98.8%). During hospitalization (median three days) 206 patients (94.9%) were free from adverse cardiac events. Stent thrombosis occurred in five patients (2.3%), Q-wave infarction in one (0.5%) and urgent percutaneous target vessel revascularization in four (1.8%). Follow-up angiography, performed in 170 patients (78.3%) showed a restenosis (/=50% diameter stenosis) in 44/170 patients (25.9%), requiring angioplasty in 29 (17.2%). A surgical revascularization was recommended in 13 patients (7.6%). One patient died during follow-up from an unknown cause; however, sudden cardiac death was most likely.PUVA stents are characterized by a high level of safety and efficacy. Clinical and angiographic results are comparable with those of other approved stents.

Next to noninvasive-recently also invasive-diagnostics, ambulant care in patients with coronary heart disease (CHD) should focus on optimal medication and prevention. The aim of this study was to evaluate actual health care quality concerning drug prescription and preventive care in patients with CHD.This prospective study was conducted from March 1999 to February 2002 at the University Hospital Bergmannsheil, Bochum, Germany. 300 patients admitted with a suspected CHD and without previous coronary angiography or myocardial infarction were enrolled. Diagnostic and therapeutic regimen complied with actual guidelines. 248 patients (82.7%) including 116 patients with angiographically confirmed CHD were examined after 1 year.On follow-up, only 70.9% of patients with confirmed CHD received a beta-blocker, 83.6% were treated with platelet aggregation inhibitors. Body mass index, portion of overweight patients, and HbA(1c) in patients with diabetes did not change during observation. After 1 year, 48.0% of the subjects had a systolic blood pressure139 mmHg, in 22.6% diastolic pressure level was89 mmHg. Blood level of low-density cholesterol exceeded the recommended range in 57.0% of the cases observed with equally high portion of inadequately treated patients in the group with confirmed CHD and in the group without CHD.Drug therapy, primary and secondary prevention in the observed subjects were fairly poor. Remarkable deficits in health care quality became obvious. There is no lack in availability of evaluated, effective and efficient measures. Thus, physicians' efforts to implement evidence-based guidelines into clinical practice have to be strengthened.

We sought to determine whether limited left atrial Maze surgery encircling each of the pulmonary veins, using cooled-tip radiofrequency (RF) ablation, is as effective as the bi-atrial approach?The original Cox/Maze operation effectively restores sinus rhythm (SR) in patients with atrial fibrillation (AF). Ablation procedures aimed at eliminating pulmonary vein foci have produced promising short-term success.This was a prospective analysis of patients with chronic AF undergoing open-heart surgery in addition to the Maze operation, using intraoperatively cooled-tip RF ablation either in the left atrium alone (group A) or in both atria (group B).Patients in group A (n = 21) and group B (n = 49) did not differ in terms of their baseline characteristics. Concomitant open-heart surgical procedures included mitral valve replacement (3 vs. 25), mitral valve plasty (0 vs. 2), mitral and aortic valve replacement (1 vs. 1), aortic valve replacement (4 vs. 6) and coronary artery bypass grafting (13 vs. 15) in groups A and B, respectively. Follow-up ranged from 1 to 50 months. The overall cumulative rates of SR were 82% in group A and 75% in group B, without a statistically significant difference (p = 0.571). Bi-atrial contraction was revealed in 92.3% of patients in SR in group A and in 79.2% in group B. The cumulative survival rates were 90.5% in group A and 77.9% in group B (p = 0.880).A left or bi-atrial Maze operation using intraoperatively cooled-tip RF ablation can safely be combined with open-heart surgery. A left atrial Maze procedure seems to be as effective as the bi-atrial procedure and restores SR in 82% of patients.

Aims This study is the first prospective randomized trial evaluating the efficacy of an antiarrhythmic surgical procedure in patients with chronic atrial fibrillation undergoing mitral valve replacement. Methods and Results Thirty consecutive patients with chronic atrial fibrillation undergoing mitral valve replacement were randomized for an additional modified MAZE-operation using intra-operatively cooled-tip radiofrequency ablation (group A) or mitral valve replacement alone (group B). Biatrial contraction was studied and functional capacity was evaluated in spiro-ergometry 6 months after surgery. Thirty-day mortality was 0% in both groups. After 12 months, sinus rhythm was reinstituted significantly more often in patients of group A (cumulative rate of sinus rhythm 0·800) compared to patients in group B (0·267) ( P

Primary success rates, and the angiographic and clinical outcome after percutaneous coronary intervention, are influenced by many different factors. Clinical features and morphologic characteristics of the target lesion are important. Also, interventionally caused endothelial trauma may trigger atherogenetic and procoagulatory factors leading to intraluminal thrombosis. The study population consisted of 228 consecutive, unselected patients with symptomatic coronary artery disease or exercise-induced myocardial ischemia and coronary artery stenoses eligible for percutaneous intervention. We analyzed different clinical, morphological, and laboratory (total cholesterol, high-density lipoprotein-cholesterol, low-density lipoprotein-cholesterol, triglycerides, fibrinogen) features in those patients with adverse cardiac events (stent thrombosis, myocardial infarction, urgent target vessel revascularization, death) after primary successful coronary artery stenting, compared with a control group without adverse events. In the group with adverse cardiac events we found a significantly higher level of fibrinogen compared with the control group. Other laboratory data and clinical characteristics were not significantly different between the two groups. The study shows a possible association between hyperfibrinogenemia and adverse cardiac events after intracoronary stenting. In clinical practice, the potential role of elevated levels of fibrinogen in an unfavorable outcome after percutaneous coronary interventions should be considered when planning coronary artery stenting.

Pacing for Treatment of Atrial Tachyarrhythmias.Introduction: Patients with bradycardia requiring permanent pacing frequently suffer from additional atrial tachyarrhythmias (ATs). This study evaluated the safety and efficacy of atrial antitachycardia pacing (ATP) and the performance of pacing for AT prevention implemented into a new pacemaker. Methods and Results: In patients with conventional indications for permanent pacing, an investigational DDDRP pacemaker (Medtronic AT500, model 7253) was implanted. The primary study objectives were to determine the safety of overall device functioning and its efficacy in terminating spontaneous AT. A secondary endpoint was to determine the reliability of AT detection. Pacemaker memory functions were used to analyze the impact of dedicated pacing algorithms on AT prevention. In 33 European and Canadian centers, 325 patients were enrolled (mean follow-up 2.3 ± 1.3 months). Complication-free survival at 3 months was 88%. In 2,145 episodes stored with atrial electrograms, AT detection was confirmed in 97%. The algorithm for continuous overdrive pacing increased the percentage of atrial pacing to 97%. After ATP activation, 16,683 of 52,468 AT episodes were treated (120 patients). Of these, 8,903 episodes (53%) were terminated successfully by ATP. No proarrhythmic effect of preventive pacing or atrial ATP was observed. Preventive pacing algorithms increased the median percentage of atrial pacing from 62% to 97%. However, the number of AT/AF (atrial fibrillation) episodes (4.1 vs 4.1 per patient per day) and the time in AT/AF (13.7% vs 12.8%) was not significantly different before and after activation of preventive pacing. Conclusion: DDDRP pacing with a new system for AT therapy was safe and associated with successful pace-termination of AT in 53% of episodes. Preventive pacing and atrial ATP algorithms represent two new functions that can be implemented safely into pacemaker systems for nonpharmacologic treatment of ATs in patients requiring pacemaker therapy.

OBJECTIVES This study prospectively analyzed atrial tachyarrhythmia (AT) organization and antitachycardia pacing (ATP) success in patients with an implanted device for AT therapy. BACKGROUND In patients with atrial fibrillation (AF), the incidence of regular, slow ATs amendable by ATP is unknown. METHODS Forty patients with previously documented AT (70% with AF) received a new pacemaker with atrial electrogram (AEG) storage and atrial ATP capabilities for standard pacing indications. The AEGs acquired during the first month (study phase 1) were classified into high (type I), intermediate (type II) and low (type III) degrees of organization. Atrial ATP was then activated, and treated AT episodes were retrieved three and six months after implantation (study phase 2). RESULTS Of 824 AEGs retrieved before ATP activation (study phase 1), 351 (43%) were classified as type I, 47% as type II and 10% as type III. Episodes of AT starting as type I (35%) and type II or III (65%) maintained their type over 1 min in 73%. All patients with an exclusive history of AF also showed type I AEGs. In 361 subsequently treated AT episodes (study phase 2), ATP was successful in 62% of type I and 34% of type II episodes, but not in type III (p CONCLUSIONS The majority of patients with a history of AF show not only disorganized but also highly organized AT episodes, which can be successfully terminated by ATP.

UNLABELLED Pacing algorithms for prevention of atrial tachyarrhythmia (AT) are under clinical evaluation. The present study prospectively evaluated the efficacy of three simultaneously active algorithms for AT prevention and aimed at identifying patients in whom atrial preventive pacing (APP) may be particularly successful. METHODS In 31 patients with conventional pacing indications and paroxysmal AT, a DDDRP pacing system was implanted, which stores 35 AT episodes with atrial electrograms and marker annotations. Counters and stored AT episodes were retrieved 30 days after implant. APP algorithms (atrial preference pacing, atrial rate stabilization, postmode switching overdrive) were activated. Counters and stored AT episodes were again retrieved 60 days later. The number and duration of AT episodes was measured. Several clinical variables were examined with respect to their ability to identify candidates for APP. RESULTS During APP, the mean number of AT episodes/patient/day decreased from 7.67 to 1.68 (P = 0.04). However, time in AT was not significantly reduced (9.45% versus 10.41%). APP decreased the number of episodes/day in 11 patients and increased it in 9 patients. No clinical parameters predicting APP success was identified. CONCLUSIONS APP using three algorithms significantly reduced the mean number of AT episodes/patient/day. However, the time during which patients were in AT was not reduced. No clinical variable predicted the success or failure of APP.