Three-dimensional intracardiac echocardiography for left atrial appendage sizing and percutaneous occlusion guidance.

AIMS: Left atrial appendage (LAA) imaging is critical during percutaneous occlusion procedures. 3D-intracardiac echocardiography (ICE) features direct visualization of LAA from multiple cross-sectional planes at a time. We aimed at reporting procedural success of 3D-ICE-guided LAA occlusion and the correlation between pre-procedural transoesophageal echocardiography (TEE) and intraprocedural 3D-ICE for LAA sizing. METHODS AND RESULTS: Among 274 patients undergoing left atrial appendage occlusion (LAAO) with a Watchman FLX, periprocedural ICE guidance was achieved via a commercially available 2D-ICE catheter (220 patients) or a novel (NUVISION™) 3D-ICE one (54 patients). Primary endpoint was a composite of procedural success and LAA sealing at follow-up TEE. Secondary endpoint was a composite of periprocedural device recapture/resizing plus presence of leaks ≥ 3 mm at follow-up TEE. 3D-ICE measurements of maximum landing zone correlated highly with pre-procedural TEE reference values [Pearson's: 0.94; P < 0.001; bias: -0.06 (-2.39, 2.27)]. The agreement between 3D-ICE-based device selection and final device size was 96.3% vs. 79.1% with 2D-ICE (P = 0.005). The incidence of the primary endpoint was 98.1% with 3D-ICE and 97.3% with 2D-ICE (P = 0.99). 2D-ICE patients had a trend towards a higher incidence of periprocedural device recapture/redeployment (31.5% vs. 44.5%; P = 0.09). The secondary endpoint occurred in 31.5% of 3D-ICE patients vs. 45.9% of 2D-ICE ones (P = 0.065). CONCLUSION: Intracardiac echocardiography-guided LAAO showed a very high success, with no major adverse events. A very high level of agreement for LAA sizing was found between pre-procedural TEE and periprocedural 3D-ICE. 3D-ICE performed significantly better than 2D-ICE for FLX size selection and may provide better guidance during device deployment.

Clinical presentation, diagnosis, and treatment of atrioesophageal fistula resulting from atrial fibrillation ablation.

BACKGROUND: Atrioesophageal fistula (AEF) is a worrisome complication of atrial fibrillation (AF) ablation. Its clinical manifestations and time course are unpredictable and may contribute to diagnostic and treatment delays. We conducted a systematic review of all available cases of AEF, aiming at characterizing clinical presentation, time course, diagnostic pitfalls, and outcomes. METHODS: The digital search retrieved 150 studies containing 257 cases, 238 (92.6%) of which with a confirmed diagnosis of AEF and 19 (7.4%) of pericardioesophageal fistula. RESULTS: The median time from ablation to symptom onset was 21 days (interquartile range [IQR]: 11-28). Neurological abnormalities were documented in 75% of patients. Compared to patients seen by a specialist, those evaluated at a walk-in clinic or community hospital had a significantly greater delay between symptom onset and hospital admission (median: 2.5 day [IQR: 1-8] vs. 1 day [IQR: 1-5); p = .03). Overall, 198 patients underwent a chest scan (computed tomography [CT]: 192 patients and magnetic resonance imaging [MRI]: 6 patients), 48 (24.2%; 46 CT and 2 MRI) of whom had normal/unremarkable findings. Time from hospital admission to diagnostic confirmation was significantly longer in patients with a first normal/unremarkable chest scan (p < .001). Overall mortality rate was 59.3% and 26.0% survivors had residual neurological deficits at the time of discharge. CONCLUSIONS: Since healthcare professionals of any specialty might be involved in treating AEF patients, awareness of the clinical manifestations, diagnostic pitfalls, and time course, as well as an early contact with the treating electrophysiologist for a coordinated interdisciplinary medical effort, are pivotal to prevent diagnostic delays and reduce mortality.

Thromboembolic events and need for anticoagulation therapy following left atrial appendage occlusion in patients with electrical isolation of the appendage.

INTRODUCTION: Electrical isolation of the left atrial appendage (LAA) is an important adjunctive ablation strategy in patients with nonparoxysmal atrial fibrillation (AF). Patients who have impaired LAA contractility following isolation may require long-term oral anticoagulant (OAC) therapy irrespective of their CHADS2 -VASc score. Percutaneous LAA occlusion (LAAO) is a potential alternative to life-long OAC therapy. We aimed to assess the rate of OAC discontinuation and thromboembolic (TE) events following percutaneous LAAO in patients who underwent LAA electrical isolation (LAAI). METHODS: This is a retrospective two-center study of patients who underwent percutaneous LAAO following LAAI. Patients with at least 3-month follow-up were included in the study. The antithrombotic therapy and TE events at the time of the last follow-up were noted. RESULTS: The LAA was successfully occluded in 162 (with Watchman device in 140 [86.4%] and Lariat in 22 [13.6%]). A total of 32 patients had leaks detected on the 45-day transesophageal echocardiogram (TEE); 21 (15%) Watchman and 11 (50%) Lariat cases (P = 0.0001). Two (one Watchman and one Lariat) of the 32 leaks were more than 5 mm. After the 45-day TEE, 150 (92.6%) patients were off-OAC. No TE events were reported in the 150 patients who stopped the anticoagulants. Four (2.47%) patients experienced stroke following the LAAO (three Watchman and one Lariat) procedure while on-OAC, two of which were fatal. At the median follow-up of 18.5 months, 159 (98.15%) patients were off-anticoagulant. CONCLUSION: Up to 98% of patients with LAAI could safely discontinue OAC after undergoing the appendage closure procedure.

Safety/Efficacy of DOAC Versus Aspirin for Reduction of Risk of Cerebrovascular Events Following VT Ablation.

OBJECTIVES: The STROKE-VT (Safety and Efficacy of Direct Oral Anticoagulant Versus Aspirin for Reduction of Risk of Cerebrovascular Events in Patients Undergoing Ventricular Tachycardia Ablation) study is a multicenter, randomized controlled trial that examined the differences in cerebrovascular events between direct oral anticoagulant (DOAC) and aspirin (ASA) use postprocedurally in patients who underwent left ventricular arrhythmia (LVA) ablation (ventricular tachycardia [VT] or premature ventricular contraction [PVC]) using radiofrequency ablation (RFA). BACKGROUND: There exists limited data regarding antiplatelet or anticoagulation strategy following LVA ablation. METHODS: A total of 246 patients scheduled for LVA-RFA were randomized 1:1 postprocedurally to receive DOACs or ASA. The study's primary endpoint was the incidence of stroke or transient ischemic attack (TIA) or asymptomatic cerebrovascular events (ACEs) detected by magnetic resonance imaging at 24 hours and 30 days of follow-up. The secondary endpoints included procedure-related complications (composite of any vascular complication, pericardial complication, heart block, and thromboembolic event, excluding stroke or TIA) and in-hospital mortality. RESULTS: There were no differences between groups regarding baseline and ablation characteristics (except the percentage of patients who underwent VT ablation, rate of amiodarone use, and total RFA time). Postprocedure cerebrovascular events (stroke and TIA) were lower in the DOAC arm versus the ASA arm (0% vs 6.5%; P < 0.001 and 4.9% vs. 18%; P < 0.001, respectively). Patients in the ASA group had more MRI-detected ACEs compared with the DOAC group both at 24-hour (23% vs 12%; P = 0.03) and 30-day (18% vs 6.5%; P = 0.006) follow-up. Acute procedure-related complications and in-hospital mortality were similar between the 2 groups. CONCLUSIONS: DOAC use following endocardial and/or epicardial ablation for LVA-RFA was associated with reduced risk of TIA or stroke and asymptomatic MRI-detected cerebrovascular events.

Catheter ablation of ventricular tachycardia in ischemic cardiomyopathy: Impact of concomitant amiodarone therapy on short- and long-term clinical outcomes.

BACKGROUND: Substrate catheter ablation of scar-related ventricular tachycardia (VT) is a widely accepted therapeutic option for patients with ischemic cardiomyopathy (ICM). OBJECTIVE: The purpose of this study was to investigate whether concomitant amiodarone therapy affects procedural outcomes. METHODS: A total of 134 consecutive patients (89% male; age 66 ± 10 years) with ICM undergoing catheter ablation of VT were included in the study. Patients were sorted by amiodarone therapy before ablation. In all patients, a substrate-based catheter ablation (endocardial ± epicardial) in sinus rhythm abolishing all "abnormal" electrograms within the scar was performed. The endpoint of the procedure was VT noninducibility. After the ablation procedure, all antiarrhythmic medications were discontinued. All patients had an implantable cardioverter-defibrillator, and recurrences were analyzed through the device. RESULTS: In 84 patients (63%), the ablation was performed on amiodarone; the remaining 50 patients (37%) were off amiodarone. Patients had comparable baseline characteristics. Mean scar size area was 143.6 ± 44.9 cm2 on amiodarone vs 139.2 ± 36.8 cm2 off amiodarone (P = .56). More radiofrequency time was necessary to achieve noninducibility in the off-amiodarone group compared to the on-amiodarone group (68.1 ± 20.1 minutes vs 51.5 ± 19.7 minutes; P <.001). In addition, due to persistent VT inducibility, more patients in the off-amiodarone group required epicardial ablation than in the on-amiodarone group (13/50 [26%] vs 5/84 [6%], respectively; P <.001). During mean follow-up of 23.9 ± 11.6 months, recurrence of any ventricular arrhythmias off antiarrhythmic drugs was 44% (37/84) in the on-amiodarone group vs 22% (11/50) in the off-amiodarone group (P = .013). CONCLUSION: Albeit, VT noninducibility after substrate catheter ablation for scar related VT was achieved faster, with less radiofrequency time and less need for epicardial ablation in patients taking amiodarone, these patients had significantly higher VT recurrence at long-term follow-up when this medication was discontinued.

Left atrial appendage tip: an unusual site of successful ablation after failed endocardial and epicardial mapping and ablation.

Uncommon sites of ablation for arrhythmias can be the cause of failed ablations. This series includes 4 cases requiring ablation at the tip of the left atrial appendage after both endocardial and epicardial mapping and ablation failed.

Epicardial Ablation Complications.

The percutaneous epicardial approach has become an adjunctive tool for electrophysiologists to treat disparate cardiac arrhythmias, including accessory pathways, atrial tachycardia, and particularly ventricular tachycardia. This novel technique prompted a strong impulse to perform epicardial access as an alternative strategy for pacing and defibrillation, left atrial appendage exclusion, heart failure with preserved ejection fraction, and genetically engineered tissue delivery. However, because of the incremental risk of major complications compared with stand-alone endocardial ablation, it is still practiced in a limited number of highly experienced centers across the world.

Outcomes of Catheter Ablation in Arrhythmogenic Right Ventricular Cardiomyopathy Without Background Implantable Cardioverter Defibrillator Therapy: A Multicenter International Ventricular Tachycardia Registry.

OBJECTIVES: This study sought to determine the long-term outcomes of catheter ablation (CA) of ventricular tachycardia (VT) in a series of patients with arrhythmogenic right ventricular cardiomyopathy (ARVC) without background implantable cardioverter-defibrillator (ICD) therapy. BACKGROUND: Endo-epicardial CA of VT has been demonstrated to be highly effective in reducing recurrent VT in patients with ARVC. METHODS: Thirty-two patients (age 45 ± 13 years, 72% male) with ARVC and VT underwent CA in the absence of ICD therapy. ICD was recommended in all cases, but implantation was not performed due to patient refusal (63%) or financial hardship (37%). CA was guided by activation/entrainment mapping for mappable VT and pace mapping/targeting of abnormal substrate in cases of unmappable VT. RESULTS: Symptoms associated with clinical VT included palpitations (78%), chest pain and shortness of breath (22%), pre-syncope (16%), and syncope (13%). Prior to ablation, 22 patients (69%) failed a mean of 1.3 ± 0.5 antiarrhythmic drugs. Epicardial mapping and ablation was performed as first-line strategy (20 [63%]) or in case of recurrent VT or persistent inducibility after endocardial-only ablation (3 [9%]-surgical epicardial cryoablation in 1 patient). After a mean of 1.6 (range 1 to 3) procedures, all patients demonstrated noninducibility of sustained VT from at least 2 RV sites; 75% also had stimulation on isoproterenol with no inducible VT. At a median follow-up of 46 months (range 26 to 65 months) following the last ablation, no deaths were observed and freedom from recurrent VT was 81%. CONCLUSIONS: In this multicenter international registry of patients with ARVC and VT, CA performed in the absence of background ICD was associated with a low rate of symptomatic VT recurrence (19%) without mortality during 46-month median follow-up. These data suggest that further prospective studies may refine selection of patients with structural heart disease at low risk for SCD, possibly obviating the benefit of ICD therapy.

Pulmonary vein antrum isolation for treatment of atrial fibrillation in patients with valvular heart disease or prior open heart surgery.

OBJECTIVES: The goal of this study was to assess the safety and efficacy of pulmonary vein antrum isolation in patients with moderate valvular heart disease or open-heart surgery and atrial fibrillation (AF). BACKGROUND: Valvular heart disease and open-heart surgery are commonly associated with AF and increase the risk of adverse events in AF patients. METHODS: A total of 391 consecutive patients who had pulmonary vein antrum isolation performed between December 2000 and December 2002 were screened. A total of 142 of these patients had clinically significant valvular disease or prior cardiac surgery. End points included AF recurrence and pulmonary vein antrum isolation complication rates. RESULTS: Patients with valvular heart disease or prior open-heart surgery were older, had larger left atria and a more advanced New York Heart Association class. They did not differ significantly with respect to gender, but had a longer history of AF. Procedure times were similar between patients with and without valvular heart disease or prior open-heart surgery. After 18 +/- 7 months in the lone AF patients, 11 +/- 5 months in patients with valvular heart disease, and 10 +/- 5 months in patients with prior open heart surgery, there was a trend toward lower recurrence of AF in patients with lone AF who enjoyed a 98% overall cure rate after up to 2 pulmonary vein antrum isolations versus 93% among patients with valvular heart disease (P = .04) and prior open heart surgery (P = .07). Complication rates were comparable between groups. CONCLUSIONS: Pulmonary vein antrum isolation is safe and effective in patients with moderate valvular heart disease and the patients who developed AF after open-heart surgery. These results have implications for our understanding of the pathophysiology of AF in patients with moderate valvular heart disease or past cardiac surgery and should be considered when discussing treatment options in these patients.

Catheter ablation of atrial fibrillation: state-of-the-art techniques and future perspectives.

The impact of atrial fibrillation on the healthcare systems of Western countries is overwhelming, due to its independent association with death, systemic thromboembolism, impaired quality of life and hospitalizations. Catheter ablation is the only treatment thus far demonstrated capable of achieving cure in a substantial proportion of patients. Pulmonary vein antrum isolation (PVAI) is the cornerstone of current atrial fibrillation ablation techniques, with the greatest efficacy as a stand-alone procedure in patients with paroxysmal atrial fibrillation. Use of general anesthesia, open-irrigated ablation catheters and maintenance of periprocedural therapeutic warfarin has been demonstrated to increase the safety and effectiveness of PVAI. In patients with paroxysmal atrial fibrillation, the systematic addition of superior vena cava isolation increases the long-term freedom from atrial fibrillation recurrence. A more extensive ablation approach extending to the entire left atrial posterior wall and to complex fractionated electrograms (CFAEs) is warranted in nonparoxysmal atrial fibrillation patients, in whom nonpulmonary vein trigger sites are frequently identified. Up to one-third of these patients experiencing atrial fibrillation recurrence after ablation have evidence of triggers from the left atrial appendage. Isolation of this structure is the best treatment strategy to improve the long-term success rate. In recent years, in addition to the development of ablation techniques to increase the success rate, outcomes of atrial fibrillation treatment trials have been reconsidered. In particular, reduction of hospitalization, stroke and mortality, as well as economic factors, have all been considered relevant to evaluate the effectiveness of atrial fibrillation treatment. Large ongoing trials are specifically evaluating the impact of atrial fibrillation ablation on these outcomes. This article will summarize the state-of-the art techniques for atrial fibrillation ablation, and will discuss the contribution of ongoing studies to the future of atrial fibrillation ablation.

Endo-epicardial homogenization of the scar versus limited substrate ablation for the treatment of electrical storms in patients with ischemic cardiomyopathy.

OBJECTIVES: This study investigated the impact on recurrences of 2 different substrate approaches for the treatment of these arrhythmias. BACKGROUND: Catheter ablation of electrical storms (ES) for ventricular arrhythmias (VAs) has shown moderate long-term efficacy in patients with ischemic cardiomyopathy. METHODS: Ninety-two consecutive patients (81% male, age 62 ± 13 years) with ischemic cardiomyopathy and ES underwent catheter ablation. Patients were treated either by confining the radiofrequency lesions to the endocardial surface with limited substrate ablation (Group 1, n = 49) or underwent endocardial and epicardial ablation of abnormal potentials within the scar (homogenization of the scar, Group 2, n = 43). Epicardial access was obtained in all Group 2 patients, whereas epicardial ablation was performed in 33% (14) of these patients. RESULTS: Mean ejection fraction was 27 ± 5. During a mean follow-up of 25 ± 10 months, the VAs recurrence rate of any ventricular tachycardia (VTs) was 47% (23 of 49 patients) in Group 1 and 19% (8 of 43 patients) in Group 2 (log-rank p = 0.006). One patient in Group 1 and 1 patient in Group 2 died at follow-up for noncardiac reasons. CONCLUSIONS: Our study demonstrates that ablation using endo-epicardial homogenization of the scar significantly increases freedom from VAs in ischemic cardiomyopathy patients.

Radiofrequency ablation of atrial fibrillation in patients with mitral or aortic mechanical prosthetic valves: a feasibility, safety, and efficacy study.

BACKGROUND: Patients with prosthetic valves have a high prevalence of atrial fibrillation (AF). We report a multicenter experience of performing pulmonary vein antral isolation (PVAI) in this challenging, high-risk cohort of patients. OBJECTIVE: The purpose of this study was to assess the feasibility, safety, and efficacy of radiofrequency (RF) ablation for sinus rhythm restoration in AF patients with mitral or aortic mechanical prosthetic valves. METHODS: A total of 50 patients with prosthetic valves (group I) who underwent RF ablation for AF between January 1, 2007, and April 30, 2009, were identified prospectively at four tertiary care centers. A matched group of 50 patients (group II) acted as controls. RESULTS: Total procedural time (199.4 ± 49 minutes vs 166.6 ± 27.5 minutes, P <.001) and fluoroscopy time (60 ± 17 minutes vs 53.8 ± 6.8 minutes, P <.01) were prolonged, with a higher incidence of atrial flutter at 3 months in group I (18% vs 6%, P = .1) compared to group II. At 12 months, 80% of patients in the valve group were in sinus rhythm after an average of 1.3 procedures, and 82% of controls were in sinus rhythm after an average 1.2 procedures (P = .9). There was a trend toward a higher nonfatal complication rate in the valve group than in the control group (8% vs 4%, P = .1). CONCLUSION: In patients with prosthetic valves, RF ablation for AF is feasible, safe, and efficacious, with a trend toward a higher nonfatal complication rate and an increased rate of postablation atrial flutter.

Safety and outcomes of cryoablation for ventricular tachyarrhythmias: results from a multicenter experience.

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.

The risk of thromboembolism and need for oral anticoagulation after successful atrial fibrillation ablation.

OBJECTIVES: The aim of this multicenter study was to evaluate the safety of discontinuing oral anticoagulation therapy (OAT) after apparently successful pulmonary vein isolation. BACKGROUND: Atrial fibrillation (AF) is associated with an increased risk of thromboembolic events (TE) and often requires OAT. Pulmonary vein isolation is considered an effective treatment for AF. METHODS: We studied 3,355 patients, of whom 2,692 (79% male, mean age 57 +/- 11 years) discontinued OAT 3 to 6 months after ablation (Off-OAT group) and 663 (70% male, mean age 59 +/- 11 years) remained on OAT after this period (On-OAT group). CHADS(2) (congestive heart failure, hypertension, age [75 years and older], diabetes mellitus, and a history of stroke or transient ischemic attack) risk scores of 1 and > or =2 were recorded in 723 (27%) and 347 (13%) Off-OAT group patients and in 261 (39%) and 247 (37%) On-OAT group patients, respectively. RESULTS: During follow-up (mean 28 +/- 13 months vs. 24 +/- 15 months), 2 (0.07%) Off-OAT group patients and 3 (0.45%) On-OAT group patients had an ischemic stroke (p = 0.06). No other thromboembolic events occurred. No Off-OAT group patient with a CHADS(2) risk score of > or =2 had an ischemic stroke. A major hemorrhage was observed in 1 (0.04%) Off-OAT group patient and 13 (2%) On-OAT group patients (p < 0.0001). CONCLUSIONS: In this nonrandomized study, the risk-benefit ratio favored the suspension of OAT after successful AF ablation even in patients at moderate-high risk of TE. This conclusion needs to be confirmed by future large randomized trials.

Transiliac ICD implantation: defibrillation vector flexibility produces consistent success.

BACKGROUND: The transiliac approach to implantable cardioverter-defibrillator (ICD) implantation is an alternative in patients for whom pectoral placements are contraindicated. The defibrillation vector is altered from the pectoral configuration because of pulse generator placement in one of the upper abdominal quadrants and separate single-coil, active-fixation defibrillation leads positioned in the high right atrium and right ventricular apex. OBJECTIVE: The feasibility, safety, and complications of this approach and the results of defibrillation testing (DFT) with this configuration are described. METHODS: Twenty-three patients (16 male and 7 female, mean age 65.7 +/- 13.2 years) required transiliac approach to ICD placement. The leads were inserted through the iliac vein immediately superior to the inguinal ligament. When required, a subcutaneous coil was tunneled posterior to the left ventricle from the left axilla. RESULTS: The right iliac vein entry was used in 17 patients, with placement of the pulse generator in the left upper quadrant in 16 patients. Atrial and ventricular lead pacing and sensing function were acceptable. Initial defibrillation success with a safety margin of 10 J was achieved in 15 patients. With the placement of an additional subcutaneous coil in the remaining 8 patients, defibrillation success with a safety margin of 10 J was increased to 19 patients, whereas defibrillation success with a safety margin of 5 J was achieved in all patients, although 1 patient required repeat testing 24 hours after implantation. There were no acute complications. Late complications occurred in 3 patients, comprised of atrial lead malfunction, device infection, and right ventricular defibrillation lead fracture. CONCLUSION: The iliac vein approach to ICD implantation is a safe and effective alternative technique. Flexibility in lead placement, defibrillation vectors, and careful DFT are required to produce a consistently effective system.

Esophageal capsule endoscopy after radiofrequency catheter ablation for atrial fibrillation: documented higher risk of luminal esophageal damage with general anesthesia as compared with conscious sedation.

BACKGROUND: Left atrioesophageal fistula is a rare but devastating complication that may occur after catheter ablation of atrial fibrillation. We used capsule endoscopy to assess esophageal injury after catheter ablation for atrial fibrillation in a population randomized to undergo general anesthesia or conscious sedation. METHODS AND RESULTS: Fifty patients undergoing atrial fibrillation ablation for paroxysmal symptomatic atrial fibrillation refractory to antiarrhythmic drugs were enrolled and randomized, including those undergoing the procedure under general anesthesia (25 patients, group 1) and those receiving conscious sedation with fentanyl or midazolam (25 patients, group 2). All patients underwent esophageal temperature monitoring during the procedure. The day after ablation, all patients had capsule endoscopy to assess the presence of endoluminal tissue damage of the esophagus. We observed esophageal tissue damage in 12 (48%) patients of group 1 and 1 esophageal tissue damage in a single patient (4%) of group 2 (P<0.001). The maximal esophageal temperature was significantly higher in patients undergoing general anesthesia (group 1) versus patients undergoing conscious sedation (group 2) (40.6+/-1 degrees C versus 39.6+/-0.8 degrees C; P< 0.003). The time to peak temperature was 9+/-7 seconds in group 1 and 21+/-9 seconds in group 2, and this difference was statistically significant (P<0.001). No complication occurred during or after the administration of the pill cam or during the procedures. All esophageal lesions normalized at the 2-month repeat endoscopic examination. CONCLUSIONS: The use of general anesthesia increases the risk of esophageal damage detected by capsule endoscopy.

Atrial fibrillation ablation strategies for paroxysmal patients: randomized comparison between different techniques.

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<0.001) after a single procedure and with antiarrhythmic drugs. CONCLUSIONS: 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.

Clinical predictors and relationship between early and late atrial tachyarrhythmias after pulmonary vein antrum isolation.

BACKGROUND: Several studies have reported early (EAT) and late (LAT) atrial tachyarrhythmias following atrial fibrillation (AF) ablation, but the factors associated with them and their clinical significance are not well known. OBJECTIVE: The purpose of this study was to investigate the predictors and the relationship between EAT and LAT after AF ablation. METHODS: A total of 1298 patients with paroxysmal (54%), persistent (18%), or permanent (28%) AF underwent intracardiac echocardiography-guided pulmonary vein antrum isolation and were followed for 41 +/- 10 months. EAT and LAT were defined as an episode of AF or atrial flutter/tachycardia lasting longer than 1 minute that occurred within the first 3 months of ablation and after 3 months postablation, respectively. RESULTS: After a single ablation procedure, EAT developed in 514 (40%) patients and LAT in 292 (22%) patients. At a multivariable analysis, longer AF duration (odds ratio [OR] 1.03), history of hypertension (OR 1.32), left atrial enlargement (OR 1.55), permanent AF (OR 1.72), and lack of superior vena cava isolation (OR 1.60) were significantly associated with EAT. Independent predictors of LAT were longer AF duration (OR 1.03), history of hypertension (OR 1.65), persistent (OR 2.17) or permanent AF (OR 2.28), and occurrence of EAT (OR 30.62). The risk of LAT was inversely related to the time to first EAT occurrence (OR 20, 54, and 1,052 in first, second, and third month, respectively). Notably, 49% of patients with EAT did not experience LAT. CONCLUSION: EAT strongly predict LAT. However, EAT did not automatically mean ablation failure. Delaying redo procedure may be appropriate during the first 2 months after ablation. Longer AF duration, hypertension, and nonparoxysmal AF are independent predictors of EAT and LAT.

Catheter ablation of ventricular fibrillation storm in patients with infiltrative amyloidosis of the heart.

Recent studies have demonstrated that premature ventricular contractions (PVCs) originating from the Purkinje system are responsible for initiation of ventricular fibrillation (VF) in patients with and without structural heart disease. Ablation of the PVCs has been shown to be feasible. We report 2 patients with repetitive VF associated with cardiac amyloidosis. Each episode of ventricular arrhythmia was preceded by monomorphic PVC. The electrical storms were drug resistant. Electrophysiological testing was performed and the sites of earliest activation were localized within the left ventricle in the absence of significant scar tissue. After ablation, PVCs subsided and there were no further VF recurrences.