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Background Catheter ablation of ventricular arrhythmias (VAs) with cryoenergy has not been widely reported. Objective The purpose of this study was to assess the feasibility and safety of cryoablation for VA. Methods Cases where cryoablation of VA was attempted as the initial strategy or was considered to prevent potential damage to other structures such as the coronary arteries, phrenic nerve, and His bundle were collected. Thirty-three patients with either normal heart or structural heart disease undergoing VA ablation using cryoenergy at six different institutions were enrolled in the study. Epicardial access was obtained when appropriate. Results Fifteen patients (7 men) underwent endocardial ablation, 13 (9 men) epicardial ablation (from the coronary sinus in 7), and 5 (2 men) aortic cusp ablation. Mean age was 54 ± 8 years, and ejection fraction was 45% ± 5%. In 15 (45%) patients, VAs were successfully ablated, whereas cryoablation was unsuccessful in the remaining 18 (55%) patients. Cryoablation was successful in all parahisian cases (100%). In three patients, epicardial cryoablation was successful after several failed attempts with open irrigated catheter. An aortic dissection occurred during catheter placement in the aortic cusp. At follow-up of 24 ± 5 months, all patients with acute success were free from clinical VA. Conclusion Use of cryoenergy for ablation of VA has excellent success for arrhythmias near the His bundle; however, success rates at other sites appear less favorable. Cryoablation may be considered as an alternative approach for reducing complications during ablation of VAs originating from sites close to other relevant cardiac structures (conduction system, coronary arteries, phrenic nerve) and, in rare cases, could be used epicardially when radiofrequency energy applications have failed.

International audience; BACKGROUND: Biventricular (BiV) stimulation is the preferred means of delivering cardiac resynchronization therapy (CRT), although left ventricular (LV)-only stimulation might be as safe and effective. B-LEFT HF is a prospective, multicenter, randomized, double-blind study aimed to examine whether LV-only is noninferior to BiV pacing regarding clinical and echocardiographic responses. METHODS: B-LEFT HF randomly assigned 176 CRT-D recipients, in New York Heart Association class III or IV, with an LV ejection fraction < or =35% and QRS > or =130 milliseconds, to a BiV (n = 90) versus LV (n = 86) stimulation group. Clinical status and echocardiograms were analyzed at baseline and 6 months after CRT-D implant to test the noninferiority of LV-only compared with BiV stimulation. RESULTS: The proportion of responders was in line with current literature on CRT, with improvement in heart failure composite score in 76.2% and 74.7% of patients in BiV and LV groups, respectively. Comparing LV versus BiV pacing, the small differences in response rates and corresponding 95% CI indicated that LV pacing was noninferior to BiV pacing for a series of response criteria (combination of improvement in New York Heart Association and reverse remodeling, improvement in heart failure composite score, reduction in LV end-systolic volume of at least 10%), both at intention-to-treat and at per-protocol analysis. CONCLUSIONS: Left ventricular-only pacing is noninferior to BiV pacing in a 6-month follow-up with regard to clinical and echocardiographic responses. Left ventricular pacing may be considered as a clinical alternative option to BiV pacing.

To the Editor: In their article on high-density substrate mapping in Brugada syndrome, Lambiase and colleagues reported striking endocardial conduction delays in such patients predominantly in the anterolateral right ventricular outflow tract.1 Complex and interesting electrophysiological data are presented, giving new insights into Brugada syndrome features. However, we feel that some methodological flaws in patient characterization, mapping procedure, and data interpretation give different perspectives to their conclusions. It is clear that concealed myocardial diseases, such as arrhythmogenic …

Patients with permanent pacemakers (PM) are at high risk of developing atrial fibrillation (AF). Minimal ventricular pacing modalities have been demonstrated to reduce AF in such patients, although they are not suitable for patients with advanced atrioventricular conduction disease. Recent evidences suggest that 3-hydroxy-3-methylglutaryl coenzyme A reductase inhibitors (i.e. statins) may represent a new strategy to prevent AF in patients at risk. In this article, we sought to review data regarding the effectiveness of statin therapy in preventing AF patients with a PM. We reviewed all available studies that assessed the effect of statin therapy on the occurrence of AF in patients with PM, implanted due to sinus node dysfunction or atrioventricular conduction disease. Moreover, a random effect inverse variance-weighted meta-analysis was performed, by entering directly the logarithm of the hazard ratio (HR) of AF provided in the multiple Cox regression analyses from each study. Three studies were identified, including 552 patients, of whom 159 received statins. Follow-up ranged from 1 to 2.77 years. Two studies (one observational and one prospective randomized) included predominantly patients with sinus node dysfunction (70% and 91% of patient population, respectively) and, consistently, showed a beneficial effect of statins on the occurrence of AF. On the other hand, the study including predominantly patients with atrioventricular block (60% of patient population) failed to show a beneficial effect of statins on AF occurrence. The HR for AF occurrence for the cumulative data was found to be 0.43 (95% confidence interval: 0.28-0.67, P < 0.001). Statistical heterogeneity between included studies was not detected (chi(2) = 1.68, P = 0.43, I(2) = 0%), although significant clinical differences were found in terms of study design, patient populations, statins use and dosage and AF-monitoring capabilities. Statins may represent a novel treatment strategy to prevent the occurrence of AF in patients with PM, especially for those who had a PM implanted due to sinus node dysfunction. Basing on our findings, a randomized clinical trial with a proper design to evaluate the utility of statins in preventing AF in these patients is warranted.

Background— Whether different ablation strategies affect paroxysmal atrial fibrillation (AF) long-term freedom from AF/atrial tachyarrhythmia is unclear. We sought to compare the effect of 3 different ablation approaches on the long-term success in patients with paroxysmal AF. Methods and Results— One hundred three consecutive patients with paroxysmal AF scheduled for ablation and presenting in the electrophysiology laboratory in AF were selected for this study. Patients were randomized to pulmonary vein antrum isolation (PVAI; n=35) versus biatrial ablation of the complex fractionated atrial electrograms (CFAEs; n=34) versus PVAI followed by CFAEs (n=34). Patients were given event recorders and followed up at 3, 6, 9, 12, and 15 months postablation. There was no statistical significant difference between the groups in term of sex, age, AF duration, left atrial size, and ejection fraction. At 1 year follow-up, freedom from AF/atrial tachyarrhythmia was documented in 89% of patients in the PVAI group, 91% in the PVAI plus CFAEs group, and 23% in the CFAEs group ( P Conclusion— No difference in terms of success rate was seen between PVAI alone and PVAI associated with defragmentation. CFAEs ablation alone had the smallest impact on AF recurrences at 1-year follow-up. These results suggest that antral isolation is sufficient to treat most patients with paroxysmal AF.

Background Pulmonary vein isolation (PVI) achieved using a cryoballoon has been shown to be safe and effective. This treatment modality has limited effectiveness for treatment of persistent atrial fibrillation (AF). Objective The purpose of this study was to evaluate a combined approach using a cryoballoon for treatment of PVI and focal radiofrequency (RF) left atrial substrate ablation for treatment of persistent AF. Methods Twenty-two consecutive patients with persistent AF were included in the study. PVI initially was performed with a cryoballoon. Left atrial complex fractionated atrial electrograms (CFAEs) then were ablated using an RF catheter. Finally, linear ablations using the RF catheter were performed. Results Eighty-three PVs, including five with left common ostia, were targeted and isolated (100%). Seventy-seven (94%) of 82 PVs targeted with the cryoballoon were isolated, and 5 (6%) required use of RF energy to complete isolation. A mean of 9.7 ± 2.6 cryoablation applications per patient was needed to achieve PVI. Median time required for cryoablation per vein was 600 seconds, and mean number of balloon applications per vein was 2.5 ± 1.0. In 19 (86%) patients in whom AF persisted after PVI, CFAE areas were ablated using the RF catheter. Two cases of transient phrenic nerve paralysis occurred. After a single procedure and mean follow-up of 6.0 ± 2.9 months, 86.4% of patients were AF-free without antiarrhythmic drugs. Conclusion A combined approach of cryoablation and RF ablation for treatment of persistent AF is feasible and is associated with a favorable short-term outcome.

Background The proximity of the phrenic nerve (PN) to cardiac tissue relevant to arrhythmias may increase the risk of PN injury. Strategies for preventing PN injury in the pericardial space are limited. Objective The purpose of this study was to compare methods for separating the PN from the epicardial surface in order to prevent PN injury. Methods Eight patients referred for epicardial ablation of arrhythmias were enrolled in the study. All patients required ablation near the PN. Endocardial and epicardial access was obtained in all patients. A three-dimensional mapping system was used to guide mapping and ablation. All patients underwent epicardial catheter ablation. Pacing via the ablation catheter identified the location of the PN. In order to prevent PN injury, four new strategies were tested in each patient. We sought to increase the distance between the epicardium and the PN by (1) placing a large-diameter balloon between the nerve and the myocardium, (2) introducing saline in steps of 20 ml until PN capture was lost or blood pressure dropped below 60 mmHg, (3) introducing air until PN capture was lost or blood pressure dropped below 60 mmHg, or (4) introducing a combination of saline and air until PN capture was lost or blood pressure dropped below 60 mmHg. Results At each step, epicardial pacing was performed to assess for PN stimulation. The combination of air and saline resulted in the greatest decrease of PN stimulation. Saline only failed in all cases. Air only and balloon placement were infrequently successful. Conclusion Controlled and progressive inflation of air and saline together with careful monitoring of hemodynamic parameters appears to be the best strategy for preventing PN injury during epicardial ablation. Placement of a large balloon in the appropriate location can be difficult.

Objective Myotonic dystrophy type 1 (DM1) is the most frequent muscular dystrophy in adults. DM1 is a multisystem disorder also affecting the heart with an increased incidence of sudden death, which has been explained with the common impairment of the conduction system often requiring pacemaker implantation; however, the occurrence of sudden death despite pacemaker implantation and the observation of major ventricular arrhythmias generated the hypothesis that ventricular arrhythmias may play a causal role as well. The aim of the study was to assess the 2-year cumulative incidence and the value of noninvasive and invasive findings as predictive factors for sudden death, resuscitated cardiac arrest, ventricular fibrillation, sustained ventricular tachycardia and severe sinus dysfunction or high-degree atrioventricular block. Methods/design More than 500 DM1 patients will be evaluated at baseline with a clinical interview, 12-lead ECG, 24-h ECG and echocardiogram. Conventional and nonconventional indications to electrophysiological study, pacemaker, implantable cardioverter defibrillator or loop recorder implantation have been developed. In the case of an indication to electrophysiological study, pacemaker, implantable cardioverter defibrillator or loop recorder implant at baseline or at follow-up, the patient will be referred for the procedure. At the end of 2-year follow-up, all candidate prognostic factors will be tested for their association with the endpoints. Trial registration ClinicalTrials.gov ID NCT00127582. Conclusion The available evidence supports the hypothesis that both bradyarrhythmias and tachyarrhythmias may cause sudden death in DM1, but the course of cardiac disease in DM1 is still unclear. We expect that this large, prospective, multicenter study will provide evidence to improve diagnostic and therapeutic strategies in DM1.

Pulmonary-vein isolation is increasingly being used to treat atrial fibrillation in patients with heart failure.In this prospective, multicenter clinical trial, we randomly assigned patients with symptomatic, drug-resistant atrial fibrillation, an ejection fraction of 40% or less, and New York Heart Association class II or III heart failure to undergo either pulmonary-vein isolation or atrioventricular-node ablation with biventricular pacing. All patients completed the Minnesota Living with Heart Failure questionnaire (scores range from 0 to 105, with a higher score indicating a worse quality of life) and underwent echocardiography and a 6-minute walk test (the composite primary end point). Over a 6-month period, patients were monitored for both symptomatic and asymptomatic episodes of atrial fibrillation.In all, 41 patients underwent pulmonary-vein isolation, and 40 underwent atrioventricular-node ablation with biventricular pacing; none were lost to follow-up at 6 months. The composite primary end point favored the group that underwent pulmonary-vein isolation, with an improved questionnaire score at 6 months (60, vs. 82 in the group that underwent atrioventricular-node ablation with biventricular pacing; P0.001), a longer 6-minute-walk distance (340 m vs. 297 m, P0.001), and a higher ejection fraction (35% vs. 28%, P0.001). In the group that underwent pulmonary-vein isolation, 88% of patients receiving antiarrhythmic drugs and 71% of those not receiving such drugs were free of atrial fibrillation at 6 months. In the group that underwent pulmonary-vein isolation, pulmonary-vein stenosis developed in two patients, pericardial effusion in one, and pulmonary edema in another; in the group that underwent atrioventricular-node ablation with biventricular pacing, lead dislodgment was found in one patient and pneumothorax in another.Pulmonary-vein isolation was superior to atrioventricular-node ablation with biventricular pacing in patients with heart failure who had drug-refractory atrial fibrillation. (ClinicalTrials.gov number, NCT00599976.)

We evaluated the diagnostic contribution and the therapeutic and prognostic implications of 3-dimensional electroanatomic mapping (EAM)-guided endomyocardial biopsy (EMB) in patients with arrhythmogenic right ventricular cardiomyopathy (ARVC).ARVC is a frequent cause of life-threatening ventricular arrhythmias and sudden death in young people. The value of current diagnostic criteria and the role of imaging techniques and EMB are still debated.We studied 30 consecutive patients (17 male, mean age 43 +/- 17 years) with a noninvasive diagnosis of ARVC according to current criteria. All patients underwent 3-dimensional EAM-guided EMB.Twenty-nine (97%) of 30 patients presented an abnormal voltage map. Histology and immunohistochemistry confirmed the diagnosis of ARVC in 15 patients, and showed active myocarditis according to Dallas criteria in the remaining 15 patients. Patients with ARVC were not distinguishable on the basis of clinical features, presence, and severity of structural and functional right ventricular abnormalities and 3-dimensional EAM findings. On the basis of clinical and histological features, a cardioverter-defibrillator was implanted in 13 patients with biopsy-proven ARVC and in 1 patient only with myocarditis. At a mean follow-up of 21 +/- 8 months, 7 (47%) patients with ARVC experienced a recurrence of symptomatic sustained ventricular arrhythmias with appropriate defibrillator intervention in all cases. All patients with myocarditis remained asymptomatic and free from arrhythmic events.Right ventricular myocarditis frequently mimics ARVC. Three-dimensional EAM-guided EMB is a safe and effective tool in differential diagnosis and in the selection of the most appropriate therapeutic strategy.

In the early phase of T1DM, the prevalence of such abnormalities are unknown. We analysed ECG features in young T1DM patients and in controls. onger mean ura on vs con ro s: 98.7±14.3 vs 90.8±11.1 ms (P

Out-of-hospital cardiac arrest (OHCA) accounts for 250.000-350.000 sudden cardiac deaths per year in the United States. The availability of automated external defibrillators (AEDs) promoted the implementation of public access defibrillation programs based on out-of-hospital early defibrillation by non-healthcare professionals.To perform a systematic review and a meta-analysis of the pooled effect of studies comparing the outcome of pts receiving cardiopulmonary resuscitation plus AED therapy (CPR+AED) vs. cardiopulmonary resuscitation (CPR) alone, both delivered by non-healthcare professionals, for the treatment of OHCA.We performed a search of the relevant literature exploring major scientific databases, carrying out a hand search of key journals, analysing conference proceedings and abstracts and discussing the topic with other researchers. Two analyses were planned to assess the outcomes of interest (survival to hospital admission and survival to hospital discharge).Three studies were selected for the meta-analysis. The first meta-analysis evidenced a RR of 1.22 (95% C.I.: 1.04-1.43) of surviving to hospital admission for people treated with CPR+AED as compared to CPR-only. The second meta-analysis showed a RR of 1.39 (95% C.I.: 1.06-1.83) of surviving to hospital discharge for people treated with CPR+AED as compared to CPR-only.The results of our meta-analysis demonstrate that programs based on CPR plus early defibrillation with AEDs by trained non-healthcare professionals offer a survival advantage over CPR-only in OHCA. The conclusions of our meta-analysis add to previous evidence in favour of developing public-health strategies based on AED use by trained layrescuers.

A 57-year-old female was referred to our hospital for radiofrequency (RF) ablation of paroxysmal drug refractory atrial fibrillation. Before ablation, a three-dimensional CT reconstruction of left atrium (LA) was provided with an integrated electroanatomic mapping system (Ensite NavX, St Jude Medical, St Paul, MN, USA). Initially, a segmental pulmonary veins (PVs) isolation guided by a decapolar variable circular mapping catheter (Lasso™, Biosense-Webster, Diamond Bar, CA, USA) was performed (Panel A). Radiofrequency applications, using an irrigated-tip catheter, …

Background Atrial fibrillation (AF) drivers outside pulmonary veins (PV) may account for failure after PV isolation. The aim of this study was to characterize pre-existent areas of complex fractionated atrial electrograms (CFAEs) recorded in right atrium (RA) and in coronary sinus (CS) during catheter-based PV isolation and to assess their relation to outcome. Methods and results With a tricuspid annulus and CS mapping, CFAEs were retrospectively identified in consecutive patients who underwent PV isolation. Of 224 patients, 161 were found to have CFAEs (81%). No clinical variable was found to be predictive of CFAEs presence. By Kaplan-Meier analysis, following a median follow-up of 23.7 months after a single ablation procedure, 62.8% of patients in the CFAEs(+) group and 85.4% of those in the CFAEs(-) group were free from recurrent atrial tachyarrhythmias (p=0.013). Multivariable Cox regression analysis showed that CFAEs evidence was an independent predictor of recurrence (p=0.007). Conclusions Pre-existent CFAEs, that can be easily identified in RA and CS during PV isolation, are a powerful independent predictor for AF recurrence. This finding may be helpful for refining AF ablation strategies.

BACKGROUND : Whether different ablation strategies affect paroxysmal atrial fibrillation (AF) termination mode and long term cure is unclear. We compared the effect of different ablation strategies on the AF termination and long term success in patients with parox-AF presenting to the electrophysiology laboratory in AF. METHODS : One hundred and three (103) consecutive patients with parox-AF scheduled for AF ablation presenting in the lab in AF were selected for this study. The patients were randomized to PVAI only (35 pts) versus bi-atrial ablation of the complex fractionated atrial electrograms (CFAE defragmentation) including the coronary sinus (34 pts) versus CFAE followed by PVAI (34 pts) Modes of AF termination were: conversion to SR, organization into AT or persistence of AF requiring cardioversion following ablation. RESULTS are summarized below: There was no significant difference between the groups in term of sex, age, AF duration, LA size and EF. Follow up after a single procedure with AAD is summarized below CONCLUSION : Defragmentation alone had the smallest impact on both acute AF termination and one year follow-up cure rate. No difference in terms of acute and chronic success was seen between PVAI alone and PVAI asoociated with defragmentation. This suggests that PV isolation is critical to cure AF in paroxysmal AF and that adjunctive strategies have minimal impact on cure rate and should not be considered in all patients.

Introduction: Transseptal puncture (TSP) is the conventional approach to assess the left atrial chamber. This technique has been widely used in interventional cardiology and, in the last years, this approach is mostly applied to electrophysiologic procedures. For atrial fibrillation (AF) ablation, two or more transseptal sheaths are often positioned in the left atrium in the majority of centers, therefore requiring two or more transseptal punctures. Theoretically, double puncture could bear additional risks or could increase the risk of persistence of septal defects. We reported the results of a retrospective analysis of a single transseptal puncture as a simplified approach for positioning multiple catheters in the left atrium during AF ablation. Methods: Between November 2003 and November 2005, 1,150 consecutive patients (mean age 54 ± 8 years, 75% men) were considered for AF ablation and underwent single transseptal puncture for positioning multiple catheters in the left atrium. Results: In only 6 of 1,150 (0.5%) cases a second transseptal puncture was required to position the ablation catheter in the left atrium. Neither acute complications related to transseptal catheterization such as atrial or aortic perforations, pericardial tamponade, thrombotic formation, or air embolism, nor complications due to the attempts of crossing the septum with the ablation catheter were reported. In all cases, each mapping catheter was properly maneuvered at different sites in the left atrium and at the pulmonary veins. In no patient was a residual septal atrial defect after the transseptal maneuvers detected during a mean follow up of 14 ± 2 months. Conclusions: This retrospective study on a large cohort of patients shows that single transseptal puncture for positioning two or more catheters in the left atrium for AF ablation is a highly successful and safe maneuver with a very low morbidity in the majority of patients. This may avoid potential complications related to a second transseptal puncture.

Aims Women have an increased risk for atrial fibrillation (AF)-related complications and there is evidence towards a reduced efficacy of the rhythm control strategy than men. A catheter-based strategy is therefore widely attractive, but the impact of gender on catheter ablation (CA) of AF remains undefined. Methods and results We included 221 consecutive patients (150 men) who underwent CA of drug-refractory AF. Gender differences in clinical presentation and outcomes were compared. Women were older ( P = 0.002), had a longer history of AF ( P = 0.04), and were more likely to have hypertension ( P = 0.04). Moreover, a concomitant valvular heart disease tended to be more common in women (32.4 vs. 23.3%; P = 0.28) and left atrium dimensions were significantly larger ( P = 0.003). However, acute success rate and complications rate were similar between genders. After 22.5 ± 11.8 months of follow-up, the overall freedom from arrhythmia recurrences was similar (83.1 vs. 82.7% in men), and a similar improvement in SF-36 quality of life scores was achieved in both groups. Conclusion Women are referred for AF ablation later with a more complex clinical pre-operative presentation. Despite this higher risk profile in women, no differences were detected in clinical outcomes. Our findings indicate that CA of AF appears to be safe and effective in women as in men.

Heart Rate Turbulence in Myotonic Dystrophy. Introduction: Myotonic dystrophy type 1 (MD1) is the most common muscular dystrophy of adult life. Cardiac involvement is characterized by disorders of atrioventricular conduction, ventricular arrhythmias, and sudden death. Heart rate turbulence (HRT) is a noninvasive risk predictor in patients affected by ischemic heart disease. The aim of our study is to assess the prognostic value of HRT in MD1 patients. Methods and Results: We performed HRT analysis by 24-hour Holter recording to calculate turbulence onset (TO) and turbulence slope (TS) in 29 MDl patients (mean age 52 ± 10 years), and in 30 patients (mean age 52 ± 13 years) with frequent ventricular arrhythmias and structurally normal heart (VANH). An electrophysiological study (EPS) tested ventricular arrhythmias inducibility in 22 MD1 patients. TO was significantly different between MD1 and VANH patients (-1.66 ± 2.04 and -2.98 ± 1.79%, respectively, P 0.01), while no difference was observed in TS between MDl and VANH patients (11.12 ± 6.46 and 9.12 ± 6 msec/beat, respectively). On EPS, sustained ventricular arrhythmias (SVA) were induced in six MD1 patients. TO was significantly different in inducible MDl patients (0.88 ± 1.95%), as compared with both noninducible (-2.49 ± 1.43%, P < 0.001) or no eligible to EPS (-1.93 ± 1.63%, P < 0.005) MD1 patients and to VANH patients (-2.98 ± 1.79%, P < 0.001). Conclusions: An impairment of TO, a measure of HRT, suggesting impaired cardiac parasympathetic activity, may be a useful, noninvasive predictor of arrhythmic risk in MDl patients.

Myotonic Dystrophy Type 1. Introduction: Conduction disturbances and arrhythmias characterize the cardiac feature of myotonic dystrophy type 1 (MD1); a myocardial involvement has been suggested as part of the cardiac disease. The aim of our study was to investigate the underlying myocardial alterations using electroanatomic mapping (CARTO) and their possible correlation with genetic and neurological findings. Methods and Results: Right atrial and ventricular CARTO maps were obtained in 13 MD1 patients. Thirteen age-matched patients with paroxysmal supraventricular tachycardia and normal heart served as controls. Unipolar voltage (UNI-v), bipolar voltage (BI-v) amplitudes, bipolar potential duration (Bi-dur), and atrial propagation time (A-pt) were measured. UNI-v and BI-v in interatrial septum, anterolateral atrial wall, and right ventricle outflow tract were lower in MD1 patients than controls (P < 0.001). Bi-dur and A-pt were longer in MD1 patients than controls (P < 0.001, P = 0.046, respectively). A significant relationship was documented between CTG triplets and the percentage of Bi-v

Aims This study is a single centre long-term experience on a consecutive cohort of patients with paroxysmal or persistent atrial fibrillation (AF) undergoing electrical disconnection of pulmonary veins (PVs) by means of catheter ablation. Long-term outcome was analyzed in relation to acute procedure success and to the clinical presentation. Methods and results Two hundred and thirty-four patients (182 males, mean age 55.9+/-10.6 years), affected by paroxysmal (78%) or persistent AF, underwent an electrophysiologically guided isolation of PVs. ECG, Holter and clinical follow-up were obtained at 1, 3, 6 and 12 months. At discharge an antiarrhythmic drug, Flecainide, was given only in cases with incomplete disconnection; Amiodarone was administered in all persistent AF pts. Successful disconnection of all PVs was achieved in 90% of cases. The rate of stable sinus rhythm maintenance was 85%, 74%, 72% and 65% at 1, 3, 6 and 12 months, respectively. The one-year arrhythmia free survival rates were higher among patients with paroxysmal AF (68% vs. 54%, P 0.008), those with complete disconnection of all PVs and in patients younger than 55 years. Conclusions The electrical disconnection of all the pulmonary veins should be the minimal endpoint of radiofrequency catheter ablation in patients with either paroxysmal or persistent AF. Incomplete disconnection of the PVs is predictive of recurrence. Long-term results of the ablation procedure were significantly better in patients with paroxysmal AF.

Target of ablation of peri-mitral flutter: mitral valve isthmus or triggers? {#article-title-2} Introduction Patients with previous ablation for atrial fibrillation (AF) may experience the recurrence of peri-mitral flutter (PMFL). These arrhythmias are usually triggered from sources that may also induce atrial fibrillation. We sought to determine whether ablation of triggers or completing mitral valve isthmus (MVI) block prevents more arrhythmia recurrences. Methods A total of 65 patients with recurrent PMFL after initial ablation of long-standing persistent AF were included in the study. Thirty-two were randomized to MVI ablation only (Group 1) and 33 were randomized to cardioversion and repeat pulmonary vein (PV) isolation plus ablation of others non-PV triggers (Group 2). Results MVI bidirectional block was achieved in all but one patient from Group 1. In Group 2, reconnection of 17 PVs was detected in 14 patients (42%, 1.21 veins per patient). With isoproterenol challenge, 44 non-PV trigger sites were identified in 28 patients (85%, 1.57 sites per patient). With a follow-up of 18 months, 27 patients (84%) from Group 1 had recurrent atrial arrhythmias and 15 remained on AAD, while 28 patients from Group 2 (85%, P < 0.0001 vs. Group 1) were free of arrhythmia off AAD. Cox regression model revealed that the ablation strategy used in Group 2 was associated with a significant lower risk of recurrence of atrial tachyarrhythmia (hazard ratio = 0.10, 95% CI = 0.04–0.28, P < 0.001). The Kaplan–Meier curves demonstrated significant better arrhythmia-free survival in Group 2 compared with Group 1 (log rank P < 0.0001). Conclusions In patients presenting with PMFL after ablation for long-standing persistent AF, MVI block had limited impact on arrhythmia recurrence. On the other hand, elimination of all PV and non-PV triggers achieved higher freedom from atrial arrhythmias at follow-up. # Comparison of sensitivity of transthoracic, transoesophageal, and intracardiac echocardiography for guiding transeptal puncture {#article-title-3} Objective Compare the sensitivity of transthoracic (TTE), transoesophageal (TEE), and intracardiac (ICE) echocardiography for guiding interatrial septum (IAS) puncture. Methods The study consisted of 208 patients (48 females, mean age 56.4 ± 11.3 years) who underwent RFA of LA because of atrial fibrillation. Transeptal puncture was performed after IAS visualization using TTE in 32 (15.4%), TEE in 26 (12.5%), ICE in 150 (72.1%) patients. Adequate contact of transeptal needle with IAS was defined as a tension of septum using echocardiographic techniques. Verification of tenting and following transeptal puncture with LA catheterization was defined as a true positive result. Lack of visualization of tenting with successful transeptal puncture under fluoroscopy was defined as a false-negative result. Results Clear visualization of the IAS using TTE technique was demonstrated in 2 (6%) cases, and the sensitivity amounted for 6.7%. Obvious verification of IAS by TEE was revealed in 20 (77%) patients, and sensitivity of this technique was 86.9%. ICE control of septum puncture was performed in 127 patients. ICE allowed visualizing septum and tenting in 125 patients and the tension of septum was unable to be determined in two cases despite of the efforts of specialists. ICE sensitivity for IAS verification was 98.4%. Conclusion ICE is the most sensitive ultrasound technique for verification of optimal location of the transeptal needle in the region of IAS comparing with TTE and TEE. # Pulmonary antrum radial-linear ablation: a new therapy for atrial fibrillation {#article-title-4} The abnormality of substrates in pulmonary vein antrum (PVA) plays a critical role in maintaining atrial fibrillation (AF). PVA radial-linear ablation (PVARA) was performed for an organized modification of substrates in paroxysmal AF. This study consisted of two phases: preclinical phase using 22 canine models with acutely induced AF, and clinical phase in patients with paroxysmal AF ( n = 15) in paired control with PV isolation. Radial-linear lesions were created from PV orifice to left atrium-PV junction in both dogs and patients. Successful creation of chronic radial-linear lesions was confirmed pathologically in dogs. The AF inducibility and duration decreased by 89 and 90%, respectively, after ablation in dogs. All the patients showed inducible AF prior to the procedure. No AF was inducible immediately after PVARA in 14 patients. The procedural time was significantly shorter in patients with PVARA than PV isolation. Within 1 week after ablation, there were six patients with early recurrent AF and seven with atrial tachycardia (AT) in PVARA group, and three patients with AF and six with AT in control. During follow-up of 6–12 months, 11 patients were free of AF and AT with four patients taking propafenone or amiodarone in the PVARA group, and nine patients free of AF and AT with seven patients taking propafenone or amiodarone in control. No complication related to the ablation developed in the two groups. This pilot study demonstrated that PVARA was a simple and safe strategy for paroxysmal AF ablation, and might provide a better long-term outcome than PV isolation. # Pulmonary vein isolation with a multi-electrode ablation catheter using duly-cycled bipolar and unipolar radiofrequency energy {#article-title-5} Background Traditional catheter ablation of atrial fibrillation (AF) requires long procedure times and high level of operator skill. A multielectrode catheter (PVAC, ablation frontier) combining circular mapping and duly-cycled bipolar and unipolar radiofrequency energy delivery has been developed to map and isolate the pulmonary veins. Aim The aim of this study to evaluate the efficacy of PVAC for pulmonary vein isolation in paroxysmal AF ablation. Methods Fifty consecutive patients with paroxysmal AF who had failed at least one anti-arrhythmic drug and eligible for catheter ablation were included in the study. All four pulmonary veins were isolated and confirmed the absence of pulmonary vein potentials with PVAC. At six months, 48 h Holter monitoring was performed to determine freedom of AF. Results All patients had structurally normal hearts with a mean duration of AF of 4.28 + 4.39 years. The mean procedure time was 109.74 + 28.35 min. Mean fluoroscopy time was 36.52 + 12.29 min. Mean number of RF applications were 27.79 + 13.80 min. The mean follow-up duration was 9.39 + 4.90 months. After AF ablation with PVAC, 36 patients completed 6-month follow-up and 25 patients (69.4%) were in sinus rhythm without drugs. No procedure-related complication was observed. Conclusions Pulmonary vein isolation using the PVAC has a success rate of ∼70% with the first ablation. # Autonomic mechanism for complex fractionated atrial electrograms: evidence by pathology {#article-title-6} Background The mechanism(s) underlying complex fractionated atrial electrograms (CFAEs) has not been well elucidated. The present study addressed to observe the histological characteristics at the area with CFAEs in canine atria to investigate the mechanism of CFAEs. Methods Ten adult mongrel dogs were involved in the present study. AF was induced through rapid atrial pacing with vagosympathetic nerve stimulation. CFAEs was recorded by Lasso catheter. Irrigated ablation was performed at sites with CFAEs. After finishing procedures above, all dogs were sacrificed and the whole hearts were taken out and fixed in 4¢Hformalin for more than 48 hours for histological examination. The specimens were divided into CFAEs group and non-CFAEs group. Serial sections were taken and stained with hematoxylin and eosin(HE) and general neural marker protein gene product 9.50(PGP9.50), respectively. Compare the characteristics of myocardial and autonomic nerve distribution between the CFAEs and non-CFAEs groups. Results Sections stained by HE: The myocardium in non-CFAEs group was well-arranged, usually in parallel with little interstitial and epicardial adipose tissue. However, the myocardium in CFAEs group distributed in disorganization with more interstitial tissue and epicardial adipose tissue. Nerve fibers and ganglionated plexi (autonomic nerves) in CFAEs group were more abundant than non-CFAEs group (7±5.4 vs. 1.9±2.7; P

Extraction of pacemaker leads represents the optimal therapy in patients with endocarditis involving the pacemaker leads. The percutaneous approach is becoming popular. However, complications of percutaneous extraction are not rare and incomplete removal of the vegetations with embolization in the pulmonary arteries has been described. This case report describes for the first time a case of incomplete removal of the fibrous sheath covering the lead, with residual tissue floating in the right atrium after pacemaker/ICD extraction. ICE monitoring was essential for early detection and correct diagnosis of this complication.

A 58-year-old woman affected by drug refractory paroxysmal atrial fibrillation (AF) was referred for pulmonary veins (PV) disconnection by radiofrequency (RF) ablation. Bidimensional echocardiography documented normal left ventricular dimension and function; a moderate enlargement of left atrium (LA) was present. Before ablation, a cardiac contrast-enhanced computed tomography was performed with multidetector CT scanner (MDCT, LightSpeed Pro 16, GE, Phy-USA). The CT scan was loaded into an electroanatomic mapping system equipped with an image integration software (CartoMerge, Biosense Webster Inc.) to provide three-dimensional CT …

Video capsule endoscopy (VCE) is a useful diagnostic tool in patients with unknown blood loss, particularly when there is a high suspicion of small bowel disease, but because of its use of radio frequency, it is relatively contraindicated in patients with a cardiac device. We report the case of a patient with an implantable cardiac defibrillator (ICD) who underwent VCE because of anaemia and previous surgery for colorectal cancer. Device interrogations were performed before and after the procedure. No interference between VCE and ICD was found. VCE is feasible and relatively safe in patients with ICDs.

We report the case of a 14-year-old boy with ventricular preexcitation. A standard, fluoroscopy guided, ablation procedure was successfully performed in a postero-midseptal region with a total fluoroscopy time of about 45 min (2430 cGy.cm(2)). A few hours after the procedure, preexcitation reappeared. A second ablation procedure was scheduled using the EnSite NavX™ mapping system. During mapping along the tricuspid groove, preexcitation suddenly disappeared due to mechanical "bumping" of the accessory pathway and it did not recover over the next 30 min. As per our routine practice, the phase of geometry reconstruction has been continuously recorded by the system; thus, an off-line analysis allowed to pinpoint the site of earliest activation and the site of mechanical bumping, where radiofrequency obtained the accessory pathway ablation. The second procedure was performed without using fluoroscopy at all. Thanks to the geometry reconstruction, the procedure was completely successful thus avoiding a further rehospitalization.

Background The risk of cerebrovascular embolic events with atrial fibrillation (AF) is potentially linked to an increased risk of cognitive decline and dementia. However, epidemiologic studies exploring the association between AF and incident dementia have reported conflicting results. Objective The purpose of this study was to perform a meta-analysis of observational studies specifically designed to evaluate the prospective relationship between AF and incident dementia. Methods We searched PubMed, CENTRAL, BioMedCentral, Embase, Cardiosource, clinicaltrials.gov, and ISI Web of Science (January 1980 to May 2012). No language restriction was applied. Two independent reviewers screened titles and abstracts to identify population-based studies that prospectively evaluated the association between AF and the incidence of dementia in patients not suffering an acute stroke and with normal cognitive function at baseline, providing the hazard ratio (HR) obtained in multiple Cox regression analyses, and adjusted for all confounding variables. Two independent reviewers assessed risk of bias according to the Cochrane Collaboration, and extracted patient and study characteristics and the adjusted HR of incident dementia with its 95% confidence interval (CI) of patients with AF vs those without AF. Results Eight studies with 77,668 patients were included in the analysis. All studies had a prospective observational design and included elderly patients (mean age range 61–84 years) with normal cognitive function at baseline, of whom 11,700 (15%) had AF. After a mean follow-up of 7.7 ± 9.1 years (range 1.8–30 years), 4773 of 73,321 (6.5%) patients developed dementia. Two studies did not report the rates of dementia at follow-up but reported the adjusted HR and were included in the pooled analysis. At pooled analysis adjusted for baseline confounders and covariates, AF was independently associated with increased risk of incident dementia (HR = 1.42 [95% CI 1.17–1.72], P Conclusion AF is independently associated with increased risk of dementia. Patients with AF should be periodically screened for dementia, which should be included among the outcomes assessed in AF treatment trials.