Acute Kidney Injury Resulting From Hemoglobinuria After Pulsed-Field Ablation in Atrial Fibrillation: Is it Preventable?

BACKGROUND: High-voltage pulses can cause hemolysis. OBJECTIVES: The authors evaluated the occurrence of hemoglobinuria after pulsed-field ablation (PFA) and its impact on renal function in patients with atrial fibrillation (AF). METHODS: A consecutive series of patients with AF undergoing PFA were included in this analysis. The initial patients who did not receive postablation hydration immediately after the procedure were classified as group 1 (n = 28), and the rest of the study patients who received planned fluid infusion (0.9% sodium chloride ≥2 L) after the procedure were categorized as group 2 (n = 75). RESULTS: Of the 28 patients in group 1, 21 (75%) experienced hemoglobinuria during the 24 hours after catheter ablation. The mean postablation serum creatinine (S-Cr) was significantly higher than the baseline value in those 21 patients (1.46 ± 0.28 mg/dL vs 0.86 ± 0.24 mg/dL, P < 0.001). Of those 21 patients, 4 (19%) had S-Cr. >2.5 mg/dL (mean: 2.95 ± 0.21 mg/dL). The mean number of PF applications was significantly higher in those 4 patients than in the other 17 patients experiencing hemoglobinuria (94.63 ± 3.20 vs 46.75 ± 9.10, P < 0.001). In group 2 patients, no significant changes in S-Cr were noted. The group 2 patients received significantly higher amounts of fluid infusion after catheter ablation than did those in group 1 (2,082.50 ± 258.08 mL vs 494.01 ± 71.65 mL, P < 0.001). In multivariable analysis, both hydration (R2 = 0.63, P < 0.01) and number of PFA applications (R2 = 0.33, P < 0.01) were independent predictors of postprocedure acute kidney injury. CONCLUSIONS: On the basis of our findings, both the number of PFA applications and postablation hydration were independent predictors of renal insult that could be prevented using planned fluid infusion immediately after the procedure.

Novel streamlined technique for left atrial appendage closure using a radiofrequency wire-based large access system.

INTRODUCTION: Transseptal puncture (TSP) to allow for large delivery sheath left atrial (LA) access remains a challenging aspect of LA appendage closure (LAAC) in patients with prior history of TSP, thick or lipomatous septum, atrial septal aneurysms, or other complex cardiac anatomies. This study investigates the use of the VersaCross large access (VLA) system (Baylis Medical/Boston Scientific) to improve procedural efficiency of LAAC compared to the standard needle workflow. METHODS AND RESULTS: Fifty LAAC procedures using WATCHMAN FLX between November 2021 and September 2022 were retrospectively analyzed comparing the VLA workflow (n = 25) to the standard needle workflow (n = 25). Study primary endpoint was time to procedural efficiency, and secondary endpoints included TSP time, acute LAAC success, fluoroscopy use, device recaptures, and periprocedural complications. Acute LAAC was successfully completed in all cases with no intraprocedural complications. TSP time was faster, but not significant, using the VLA workflow compared to the standard RF needle workflow (2.6 ± 1.1 min vs. 3.0 ± 1.8 min, p = 0.38). Time to WATCHMAN sheath in LA from TSP was 27% faster (1.5 ± 0.8 min vs. 2.1 ± 0.9 min; p = 0.03), and time to WATCHMAN release from TSP was 19% faster (10.5. ± 2.5 min vs. 13.0 ± 3.7 min; p = 0.01) with the VLA workflow. Overall procedure time was 15% faster (30.4 ± 5.1 min vs. 36.0 ± 6.6 min; p = 0.003) using VLA. Fluoroscopy time was 25% lower (4.0 ± 2.2 min vs. 5.5 ± 2.3 min; p = 0.003) and fluoroscopy dose was 60% lower (97.0 ± 91.7 mGy vs. 241.8 ± 240.6 mGy; p = 0.01) and more consistent [F-test, p ˂ 0.0001] using the VLA workflow compared to the needle workflow. CONCLUSION: The VLA system streamlines LAAC procedures, improving LAAC efficiency and reducing fluoroscopy use by allowing for de novo dilation of the septum for large-bore delivery sheaths, and reducing device exchanges and delivery sheath manipulation.

Prevalence of atrial fibrillation and procedural outcome in patients undergoing catheter ablation for premature ventricular complexes.

INTRODUCTION: Atrial fibrillation (AF) and premature ventricular complexes (PVC) are common arrhythmias. We aimed to investigate AF prevalence in patients with PVC and its impact on PVC ablation outcomes. METHODS: Consecutive patients undergoing PVC ablation at a single institution between 2016 and 2019 were included and prospectively followed for 2 years. Patients with severe valvular heart disease, hyperthyroidism, malignancy, alcohol use disorder and advanced renal/hepatic diseases were excluded. Twelve-lead electrocardiograms were used to diagnose AF and assess PVC morphology. All PVCs were targeted for ablation using 4-mm irrigated-tip catheters at standardized radiofrequency power guided by 3-D mapping and intracardiac echocardiography. Patients were followed with remote monitoring, device interrogations and office visits every 6 months for 2 years. Detection of any PVCs in follow-up was considered as recurrence. RESULTS: A total of 394 patients underwent PVC ablation and 96 (24%) had concurrent AF. Patients with PVC and AF were significantly older (68.2 ± 10.8 vs. 58.3 ± 15.8 years, p < .001), had lower LV ejection fraction (43.3 ± 13.3% vs. 49.6 ± 12.4%, p < .001), higher CHA2 DS2 -VASc (2.8 ± 1.3 vs. 2.0 ± 1.3, p < .001) than those without. PVCs with ≥2 morphologies were detected in 60.4% and 13.7% patients with vs without AF (p < .001). At 2-year follow-up, PVC recurrence rate was significantly higher in patients with vs without AF (17.7% vs. 9.4%, p = .02). CONCLUSION: AF was documented in 1/4 of patients undergoing PVC ablation and was associated with lower procedural success at long-term follow-up. This was likely attributed to older age, worse LV function and higher prevalence of multiple PVC morphologies in patients with concurrent AF.

Endocardial Scar-Homogenization With vs Without Epicardial Ablation in VT Patients With Ischemic Cardiomyopathy.

OBJECTIVES: In this study, the authors investigated the ablation success of scar homogenization with combined (epicardial + endocardial) vs endocardial-only approach for ventricular tachycardia (VT) in patients with ischemic cardiomyopathy (ICM) at 5 years of follow-up. BACKGROUND: Best ablation approach to achieve long-term success rate in VT patients with ICM is not known yet. METHODS: Consecutive ICM patients undergoing VT ablation at our center were classified into group 1: endocardial + epicardial scar homogenization and group 2: endocardial scar homogenization. Patients with previous open heart surgery were excluded. Epicardial ablation was performed despite being noninducible after endocardial ablation in all group 1 patients. All patients underwent bipolar substrate mapping with standard scar settings defined as normal tissue >1.5 mV and severe scar <0.5 mV. Noninducibility of monomorphic VT was the procedural endpoint in both groups. Patients were followed up every 4 months for 5 years with implantable device interrogations. RESULTS: A total of 361 patients (group 1: n = 70 and group 2: n = 291) were included in the study. At 5 years, 81.4% (n = 57/70) patients from group 1 and 66.3% (n = 193/291) from group 2 were arrhythmia-free (P = 0.01) Of those patients, 26 of 57 (45.6%) and 172 of 193 (89.1%) from group 1 and group 2 respectively were on anti-arrhythmic drugs (AAD) (log-rank P < 0.001). After adjusting for age, sex, and obstructive sleep apnea, endo-epicardial scar homogenization was associated with a significant reduction in arrhythmia-recurrence (HR: 0.48; 95% CI: 0.27-0.86; P = 0.02). CONCLUSIONS: In this series of patients with ICM and VT, epicardial substrate was detected in all group 1 patients despite being noninducible after endocardial ablation. Moreover, combined endo-epicardial scar homogenization was associated with a significantly higher success rate at 5 years of follow-up and a substantially lower need for antiarrhythmic drugs after the procedure compared with the endocardial ablation alone.

Intracardiac Echocardiography to Guide Catheter Ablation of Atrial Fibrillation.

Intracardiac echocardiography (ICE) is a valuable tool and should be standard of care in any modern electrophysiology laboratory. Through real-time imaging of cardiac anatomy, ICE is used to guide electrophysiology procedures and monitor for complications. This article is a short overview of the application of real-time ICE imaging during atrial fibrillation ablation procedures.

Primary Outcome Evaluation of a Next-Generation Left Atrial Appendage Closure Device: Results From the PINNACLE FLX Trial.

BACKGROUND: Left atrial appendage (LAA) occlusion provides an alternative to oral anticoagulation for thromboembolic risk reduction in patients with nonvalvular atrial fibrillation. Since regulatory approval in 2015, the WATCHMAN device has been the only LAA closure device available for clinical use in the United States. The PINNACLE FLX study (Protection Against Embolism for Nonvalvular AF Patients: Investigational Device Evaluation of the Watchman FLX LAA Closure Technology) evaluated the safety and effectiveness of the next-generation WATCHMAN FLX LAA closure device in patients with nonvalvular atrial fibrillation in whom oral anticoagulation is indicated, but who have an appropriate rationale to seek a nonpharmaceutical alternative. METHODS: This was a prospective, nonrandomized, multicenter US Food and Drug Administration study. The primary safety end point was the occurrence of one of the following events within 7 days after the procedure or by hospital discharge, whichever was later: death, ischemic stroke, systemic embolism, or device- or procedure-related events requiring cardiac surgery. The primary effectiveness end point was the incidence of effective LAA closure (peri-device flow ≤5 mm), as assessed by the echocardiography core laboratory at 12-month follow-up. RESULTS: A total of 400 patients were enrolled. The mean age was 73.8±8.6 years and the mean CHA2DS2-VASc score was 4.2±1.5. The incidence of the primary safety end point was 0.5% with a 1-sided 95% upper CI of 1.6%, meeting the performance goal of 4.2% (P<0.0001). The incidence of the primary effectiveness end point was 100%, with a 1-sided 95% lower CI of 99.1%, again meeting the performance goal of 97.0% (P<0.0001). Device-related thrombus was reported in 7 patients, no patients experienced pericardial effusion requiring open cardiac surgery, and there were no device embolizations. CONCLUSIONS: LAA closure with this next-generation LAA closure device was associated with a low incidence of adverse events and a high incidence of anatomic closure. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT02702271.

Use of a multi-electrode radiofrequency balloon catheter to achieve pulmonary vein isolation in patients with paroxysmal atrial fibrillation: 12-Month outcomes of the RADIANCE study.

BACKGROUND: The RADIANCE first-in-man study evaluated acute (3-month) safety and design concept in terms of utility of a new multi-electrode radiofrequency (RF) balloon catheter (HELIOSTAR, Biosense Webster) to achieve pulmonary vein isolation (PVI). After study conclusion, a subset of patients was followed up to 12 months. METHODS: Patients with drug refractory paroxysmal atrial fibrillation were enrolled. Neurological assessment, cardiac and cerebral magnetic resonance imagings were performed pre and post procedure. Ablation was delivered at 15 Watts to each PV for 60 seconds (electrodes adjacent to the posterior wall limited to 20 seconds). Adenosine or isoproterenol was administered to confirm PVI. Esophageal endoscopy was performed 48 hours post procedure. Patients were clinically followed up for 12 months. RESULTS: Thirty-nine patients underwent catheter ablation from four centers. Mean age was 60.7 ± 10.0 years with 23 (57.5%) being male. Confirmation of PVI was performed in all PVs treated (152/152). Confirmation of isolation after one delivery was performed solely on 137 of 152 PVs of which 79.6% (109/137) achieved isolation with a single delivery of RF energy. Acute PV reconnection was seen in 4.6% (7/150) of PVs. Freedom from documented atrial arrhythmia at 12 months in those followed up was 86.4% (32/37). A total of 75.7% (28/37) of patients were free from atrial arrhythmia and off antiarrhythmic medications. CONCLUSION: The HELIOSTAR RF balloon catheter allows for rapid and safe PVI with majority of PVs only requiring one application.

First Experience of Transcatheter Leak Occlusion With Detachable Coils Following Left Atrial Appendage Closure.

OBJECTIVES: The aim of this study was to assess the feasibility and efficacy of transcatheter leak closure with detachable coils in patients with incomplete left atrial appendage (LAA) closure. BACKGROUND: Incomplete LAA closure is common after interventional therapies targeting the LAA, potentially hindering effective thromboembolic prevention. Detachable coils have found a wide range of applications for transcatheter vascular occlusion and embolization procedures. METHODS: Thirty consecutive patients at high thromboembolic risk with clinically relevant residual leaks (mean age 72 ± 9 years, 73.3% men, mean CHA2DS2-VASc score 4.4 ± 1.4, mean HAS-BLED score 3.6 ± 0.8) underwent percutaneous closure of the LAA patency using embolization coils. Transesophageal echocardiography was performed at 60 ± 15 days post-procedure. RESULTS: LAA closure had been previously attempted with the Watchman device in 25 patients, the Amulet device in 2 patients, and the LARIAT device in 3 patients. Baseline transesophageal echocardiography documented moderate and severe leaks in 20 (66.7%) and 10 (33.3%) patients, respectively. After a single procedure, 25 patients (83.3%) showed complete LAA sealing or minimal leaks. Five patients (16.7%) had moderate residual leaks; 3 patients of them were offered repeat procedures. Mean procedure and fluoroscopy times were 76 ± 41 min and 21 ± 14 min, respectively; the mean volume of iodinated contrast medium used was 80 ± 47 ml. Coil deployment was successful in all cases. The overall complication rate was 6.1%. After a median follow-up period of 54 days (range 43 to 265 days) and an average of 1.1 procedures/patient, transesophageal echocardiography revealed complete LAA sealing or negligible residual leaks in 28 patients (93.3%; 25 with no residual leak, 3 patients with minimal to mild residual leaks) and moderate residual leaks in 2 patients (6.7%). CONCLUSIONS: Transcatheter LAA leak occlusion using endovascular coils appears to be a safe, effective, and promising approach in patients at high echo time risk with incomplete LAA closure. (Transcatheter Leak Closure With Detachable Coils Following Incomplete Left Atrial Appendage Closure Procedures [TREASURE]; NCT03503253).

Pulmonary Vein Isolation With a Novel Multielectrode Radiofrequency Balloon Catheter That Allows Directionally Tailored Energy Delivery: Short-Term Outcomes From a Multicenter First-in-Human Study (RADIANCE).

BACKGROUND: Balloon catheters facilitate pulmonary vein (PV) isolation, but current technology is limited by either a single ablative element, potentially leading to over-ablation of thin and under-ablation of thick tissue, or prolonged procedure times. Visualized by electroanatomical mapping, a novel compliant radiofrequency balloon catheter with 10 irrigated, flexible electrodes can simultaneously and independently deliver energy. Herein, we evaluated the feasibility, safety, and short-term efficacy of this radiofrequency balloon in a multicenter, single-arm, first-in-human study. METHODS: Paroxysmal atrial fibrillation patients underwent PV isolation with the radiofrequency balloon delivered over-the-wire with a deflectable 13.5F sheath. Radiofrequency energy is delivered simultaneously from all electrodes-up to 30 s posteriorly and 60 s anteriorly. Esophageal temperature was monitored in all patients; the esophagus was also mechanically deviated in 10 patients. RESULTS: At 4 sites, 39 patients were treated by 9 operators. The radiofrequency balloon isolated all targeted PVs (152/152), 79.6% with a single application. Electrical reconnection occurred in only 7/150 PVs (4.7%) on adenosine/isoproterenol challenge. Mean procedure, balloon dwell, and fluoroscopy times were 101.6, 40.5, and 17.4 min, respectively. Esophagogastroduodenoscopy revealed asymptomatic esophageal erythema in 5 patients. Phrenic nerve palsy occurred in a patient in whom phrenic pacing was inadvertently omitted. At 3 months, imaging revealed no PV stenosis, and early atrial arrhythmia recurrence occurred in only 10/39 (25.6%) patients. CONCLUSIONS: The compliant radiofrequency balloon can directionally tailor energy delivery for efficient, effective, and reasonably safe acute PV isolation. CLINICAL TRIAL REGISTRATION: URL: https://www.clinicaltrials.gov. Unique identifier: ISRCTN 11764506.

Vdrive Evaluation of Remote Steering and Testing in Lasso Electrophysiology Procedures Study: The VERSATILE Study in Atrial Fibrillation Ablation.

INTRODUCTION: Circular mapping catheters (CMC) are an essential tool in most atrial fibrillation ablation procedures. The Vdrive™ with V-Loop™ system enables a physician to remotely manipulate a CMC during electrophysiology studies. Our aim was to compare the clinical performance of the system to conventional CMC navigation according to efficiency and safety endpoints. METHODS AND RESULTS: A total of 120 patients scheduled to undergo a CMC study followed by pulmonary vein isolation (PVI) were included. Treatment allocation was randomized 2:1, remote navigation:manual navigation. The primary effectiveness endpoint was assessed based on both successful navigation to the targeted pulmonary vein (PV) and successful recording of PV electrograms. All PVs were treated independently within and between patients. The primary safety endpoint was assessed based on the occurrence of major adverse events (MAEs) through seven days after the study procedure. Primary effectiveness endpoints were achieved in 295/302 PVs in the Vdrive arm (97.7%) and 167/167 PVs in the manual arm (100%). Effectiveness analysis indicates Vdrive non-inferiority (pnon-inferiority = 0.0405; δ = -0.05) per the Cochran-Mantel-Haenszel test adjusted for PV correlation. Five MAEs related to the ablation procedure occurred (three in the Vdrive arm-3.9%; two in the manual arm-2.33%). No device-related MAEs were observed; safety analysis indicates Vdrive non-inferiority (pnon-inferiority = 0.0441; δ = 0.07) per the normal Z test. CONCLUSION: Remote navigation of a CMC is equivalent to manual in PVI in terms of safety and effectiveness. This allows for single-operator procedures in conjunction with a magnetically guided ablation catheter.

Management of Periprocedural and Early Pericardial Effusions With Tamponade Following Ablation of Atrial Fibrillation With Uninterrupted Factor Xa Inhibitors: A Case Series.

INTRODUCTION: Because of the absence of a dedicated reversal agent, the outcome of pericardial effusion (PE) following procedures performed with uninterrupted apixaban or rivaroxaban is unknown. We report the characteristics of PEs presenting with tamponade in patients undergoing AF ablation with uninterrupted factor Xa inhibition (FXaI) to understand their management and prognosis. METHODS AND RESULTS: We performed a multicenter cross-sectional survey in 10 centers across the United States. Patient data were obtained by chart review. In all patients the procedure was performed with uninterrupted FXaI. A total of 16 PEs requiring intervention were reported from 5 centers. Two patients were on apixaban 5 mg BD, the remaining on rivaroxaban 20 mg OD. Eleven PEs occurred in the periprocedural setting, and 5 PEs occurred from 1 to 28 days after the procedure. Pericardiocentesis and drainage were performed in all cases. Protamine and 4-factor prothrombin complex concentrate (4F-PCC) were given in all periprocedural cases. Two patients required surgery: in one case coagulation of the pericardial blood prevented effective drainage, and in the other bleeding was secondary to a steam pop-induced atrial tear. None of the postprocedural cases required FXaI reversal and the dose of rivaroxaban was temporarily reduced. No fatal outcomes or thromboembolic events were reported. CONCLUSION: Pericardiocentesis and drainage with FXaI reversal proved effective in the management of acute PEs with tamponade occurring periprocedurally in patients undergoing AF ablation with uninterrupted FXaI. Early postprocedural effusions can be treated with pericardiocentesis without the need of a reversal agent.

Hybrid Procedure (Endo/Epicardial) versus Standard Manual Ablation in Patients Undergoing Ablation of Longstanding Persistent Atrial Fibrillation: Results from a Single Center.

INTRODUCTION: Ablation of longstanding persistent atrial fibrillation (LSPAF) is the most challenging procedure in the treatment of AF, either by surgical or by percutaneous approach. OBJECTIVE: We investigated the difference in success and complication rates between combined surgical epicardial and endocardial catheter ablation procedure and our standard endocardial ablation procedure. METHODS AND RESULTS: Twenty-four consecutive patients (group 1) with LSPAF and enlarged left atrium (>4.5 cm) underwent a combined procedure, consisting of surgical, closed-chest, epicardial, radiofrequency ablation (nContact, NC, USA) via pericardial access, and concomitant endocardial ablation (hybrid procedure). Procedural complications and long-term outcomes were compared to those of 35 consecutive patients who refused the hybrid procedure and underwent standard endocardial only ablation (group 2). Baseline characteristics were comparable. In group 1, 1 patient (4.2%) developed post-procedural cardio-embolic stroke and 3 (12.5%) died (1 atrio-esophageal fistula, 1 fatal stroke, 1 of unknown cause in early follow-up), while no strokes or deaths occurred in group 2. Overall complication rates were higher for group 1 (P = 0.036). At 24-month follow-up, 4 (19%) patients in group 1 and 19 (54.3%) in group 2 were arrhythmia-free after a single procedure, on or off antiarrhythmic drugs (P<0.001). Total procedural time (276.9 ± 63.5 vs. 203.15 ± 67.3 minutes) and length of hospital stay (5 [IQR 3-8] vs. 1 [IQR 1-3] days were significantly shorter for group 2 (P <0.001). CONCLUSIONS: In patients with LSPAF and enlarged left atrium, a concomitant combined surgical/endocardial ablation approach increases complication rate and does not improve outcomes when compared to extensive endocardial ablation only.

Catheter ablation of inappropriate sinus tachycardia.

Catheter ablation for inappropriate sinus tachycardia (IST) is recommended for patients symptomatic for palpitations and refractory to other treatments. The current approach consists in sinus node modification (SNM), achieved by ablation of the cranial part of the sinus node to eliminate faster sinus rates while trying to preserve chronotropic competence. This approach has a limited efficacy, with a very modest long-term clinical success. To overcome this, proper patient selection is crucial and an epicardial approach should always be considered. This brief review will discuss the current role and limitations of catheter ablation in the management of patients with IST.

Pulmonary Vein Isolation Using the Visually Guided Laser Balloon: Results of the U.S. Feasibility Study.

INTRODUCTION: Visually guided laser balloon (VGLB) ablation is unique in that the operator delivers ablative energy under direct visual guidance. In this multicenter study, we sought to determine the feasibility, efficacy, and safety of performing pulmonary vein isolation (PVI) using this VGLB. METHODS: Patients with symptomatic, drug-refractory paroxysmal atrial fibrillation (AF) underwent PVI using the VGLB with the majority of operators conducting their first-ever clinical VGLB cases. The primary effectiveness endpoint was defined as freedom from treatment failure that included: Occurrence of symptomatic AF episodes ≥1 minutes beyond the 90-day blanking, the inability to isolate 1 superior and 2 total PVs, occurrence of left atrial flutter or atrial tachycardia, or left atrial ablation/surgery during follow-up. RESULTS: A total of 86 patients (mean age 56 ± 10 years, 67% male) were treated with the VGLB at 10 US centers. Mean fluoroscopy, ablation, and procedure times were 39.8 ± 24.3 minutes, 205.2 ± 61.7 minutes, and 253.5 ± 71.3 minutes, respectively. Acute PVI was achieved in 314/323 (97.2%) of targeted PVs. Of 84 patients completing follow-up, the primary effectiveness endpoint was achieved in 50 (60%) patients. Freedom from symptomatic or asymptomatic AF was 61%. The primary adverse event rate was 16.3% (8.1% pericarditis, phrenic nerve injury 5.8%, and cardiac tamponade 3.5%). There were no cerebrovascular events, atrioesophageal fistulas, or significant PV stenosis. CONCLUSIONS: This multicenter study of operators in the early stage of the learning curve demonstrates that PVI can be achieved with the VGLB with a reasonable safety profile and an efficacy similar to radiofrequency ablation.

Endocardial (Watchman) vs epicardial (Lariat) left atrial appendage exclusion devices: Understanding the differences in the location and type of leaks and their clinical implications.

BACKGROUND: Watchman and Lariat left atrial appendage (LAA) occlusion devices are associated with LAA leaks postdeployment. OBJECTIVE: The purpose of this study was to compare the incidence, characteristics, and clinical significance of these leaks. METHODS: We performed a multicenter prospective observational study of all patients who underwent LAA closure. Baseline, procedural, and imaging variables along with LAA occlusion rates at 30-90 days and 1-year postprocedure were compared. RESULTS: A total of 478 patients (219 with the Watchman device and 259 with the Lariat device) with successful implants were included. Patients in the Lariat group had a higher CHADS2 (congestive heart failure, hypertension, age >74 years, diabetes, stroke) score and a larger left atrium and LAA. A total of 79 patients (17%) had a detectable leak at 1 year. More patients in the Watchman group had a leak compared with those in the Lariat group (46 [21%] vs 33 [14%]; P = .019). All the leaks were eccentric (edge effect) in the Watchman group and concentric (gunny sack effect) in the Lariat group. The size of the leak was larger in the Watchman group than in the Lariat group (3.10 ± 1.5 mm vs 2.15 ± 1.3 mm; P = .001). The Watchman group had 1 device embolization requiring surgery and 2 pericardial effusions requiring pericardiocentesis. In the Lariat group, 4 patients had cardiac tamponade requiring urgent surgical repair. Three patients in each group had a cerebrovascular accident and were not associated with device leaks. CONCLUSION: The Lariat device is associated with a lower rate of leaks at 1 year as compared with the Watchman device, with no difference in rates of cerebrovascular accident. There was no correlation between the presence of residual leak and the occurrence of cerebrovascular accident.

Long-term outcome of catheter ablation in atrial fibrillation patients with coexistent metabolic syndrome and obstructive sleep apnea: impact of repeat procedures versus lifestyle changes.

INTRODUCTION: Metabolic syndrome (MS) and obstructive sleep apnea (OSA) are well-known independent risk factors for atrial fibrillation (AF) recurrence. This study evaluated ablation outcome in AF patients with coexistent MS and OSA and influence of lifestyle modifications (LSM) on arrhythmia recurrence. METHODS AND RESULTS: We included 1,257 AF patients undergoing first catheter ablation (30% paroxysmal AF). Patients having MS + OSA were classified into Group 1 (n = 126; 64 ± 8 years; 76% male). Group 2 (n = 1,131; 62 ± 11 years; 72% male) included those with either MS (n = 431) or OSA (n = 112; no CPAP users) or neither of these comorbidities (n = 588). Patients experiencing recurrence after first procedure were divided into 2 subgroups; those having sporadic events (frequency < 2 months) remained on previously ineffective antiarrhythmic drugs (AAD) and aggressive LSM, while those with persistent arrhythmia (incessant or ≥2 months) underwent repeat ablation. After 34 ± 8 months of first procedure, 66 (52%) in Group 1 and 386 (34%) in Group 2 had recurrence (P < 0.001). Recurrence rate in only-MS, only-OSA, and without MS/OSA groups were 40%, 38%, and 29%, respectively. Patients with MS + OSA experienced substantially higher recurrence compared to those with lone MS or OSA (52% vs. 40% vs. 38%; P = 0.036). Of the 452 patients having recurrence, 250 underwent redo-ablation and 194 remained on AAD and LSM. At 20 ± 6 months, 76% of the redo group remained arrhythmia-free off AAD whereas 74% of the LSM group were free from recurrence (P = 0.71), 33% of which were off AAD. CONCLUSIONS: MS and OSA have additive negative effect on arrhythmia recurrence following single procedure. Repeat ablation or compliant LSM increase freedom from recurrent AF.

Administration of isoproterenol and adenosine to guide supplemental ablation after pulmonary vein antrum isolation.

BACKGROUND: Pulmonary vein antrum isolation (PVAI) remains associated with atrial fibrillation (AF) recurrence. We administered adenosine and isoproterenol (ISP) after PVAI to uncover non-PV atrial triggers and PV reconnection, potentially increasing ablation success rate. METHODS: One hundred and ninety-two consecutive patients with symptomatic AF presenting for PVAI were prospectively studied (group 1). Following PVAI, adenosine (18-24 mg) and ISP (20-30 mcg/min) were administered intravenously. Supplemental ablation was performed in patients with non-PV triggers that induced AF (group 1A). Other subgroups included patients with (group 1B) or without (group 1C) consistent non-PV atrial foci that did not induce AF. A cohort of 196 matched control patients undergoing PVAI without drug challenge was used for comparison (group 2). RESULTS: A total of 132 atrial non-PV foci were revealed (31 inducing AF). The majority of atrial foci were observed with ISP (113/132, 86%). Less than 5% of patients had persistent PV recovery during the drug challenge. During a mean follow-up of 22 ± 8 months, PVAI was successful in 110/192 (57%, group 1) versus 100/196 (52%, group 2), P = 0.038. Furthermore, the success rate was statistically different between group 1A (25/32, 78%), group 1B (28/83, 34%), and group 1C (57/74, 74%), P < 0.001. CONCLUSION: After PVAI, ablation guided by the administration of adenosine and ISP to target non-PV triggers inducing AF increased AF ablation outcomes. Patients with non-PV foci that did not induce AF had no further ablation, with the lowest ablation success rate. This group may likely benefit from further ablation after PVAI.

Impact of cardiac resynchronization therapy on the severity of mitral regurgitation.

AIMS: Functional mitral regurgitation (MR) could be managed by both cardiac resynchronization therapy (CRT) and mitral-valve surgery. Clinical decision making regarding the appropriateness of mitral-valve surgery vs. CRT is a challenging task. This study assessed the prevalence and prognosis of various degrees of functional MR in CRT candidates. Additionally, we sought to identify functional MR patients who either can be adequately managed by CRT only or will need surgery. METHODS AND RESULTS: Cardiac resynchronization therapy recipients (n= 794) were followed-up for 26 ± 18 months. Mitral regurgitation severity was quantified on scale 0-4. Cardiac resynchronization therapy responders were identified based on improvement in the New York Heart Association class and left-ventricular ejection fraction. Severity of MR and LV reverse remodelling were assessed at 3 and 12 months. Predictors of long-term MR change and CRT response were explored with multivariable models. Mitral regurgitation was present in 86%, with 35% prevalence of advanced MR (grade 3-4). Improvement of MR ≥ 1° after 12 months occurred in 46% of patients. It was relatively more frequent in patients with advanced MR at baseline (63%, P< 0.01). Baseline MR severity and change in MR at 3-month follow-up predicted response to CRT. Patients with ≥ 1° MR improvement at 12 months had more reverse remodelling compared with those with no change or worsening of MR. CONCLUSIONS: Mitral regurgitation improvement at 3 months predicts CRT response and MR improvement at 12-month follow-up. This finding could have implications for subsequent MR surgical therapies.

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.

Stiff left atrial syndrome after catheter ablation for atrial fibrillation: clinical characterization, prevalence, and predictors.

BACKGROUND: There have been no studies of atrial diastolic function after catheter ablation of atrial fibrillation (AF). We encountered a few patients with symptomatic left atrial (LA) diastolic dysfunction and associated pulmonary hypertension (PH) that developed after catheter ablation for atrial fibrillation. Similar findings were described in patients after cardiac surgery and were referred to as the "stiff left atrial syndrome." OBJECTIVE: The purpose of this study was to prospectively quantify the incidence of patients developing PH associated with diastolic hemodynamic abnormalities of the LA after radiofrequency ablation of AF and to identify the possible predictors. METHODS: Between January 2009 and July 2010, data on 1,380 consecutive patients were prospectively collected. Before ablation and at follow-up, all patients had an echocardiogram to assess for the presence of PH. Patients with no echocardiographic evidence of PH but complaining of unexplained dyspnea with LA diastolic abnormalities were evaluated with right heart catheterization (RHC). Patients were included in the analysis if they developed new or worsening PH postablation with evidence of LA diastolic dysfunction by RHC or direct LA pressure measurement. All patients were evaluated for pulmonary vein stenosis and excluded if this condition was identified. RESULTS: The mean age was 62 ± 11 (75% male), and nonparoxysmal AF was the predominant arrhythmia (71%). New or worsening PH with associated LA diastolic abnormalities was detected in 19 (1.4%) patients after ablation. The prevalence of PH did not differ between AF types (P = .612). Compared with patients who did not develop PH, LA scarring (P <.001), diabetes (P = .026), and obstructive sleep apnea (OSA; P = .006) were more frequently observed among those who developed PH. In a multivariable logistic model, preprocedure LA size ≤45 mm (odds ratio [OR] = 6.13; P = .033), mean LA pressure (OR 1.14; P = .025), severe LA scarring (OR = 4.4; P = .046), diabetes mellitus (OR = 9.5; P = .004), and OSA (OR = 6.2; P = .009) were independently associated with the development of PH postablation. CONCLUSIONS: After radiofrequency catheter ablation of atrial fibrillation (RFCAF), PH with LA diastolic dysfunction or the so-called stiff LA syndrome is a rare but potentially significant complication of AF ablation. Severe LA scarring, LA ≤45 mm, diabetes mellitus, OSA, and high LA pressure are clinical variables that predict the development of this syndrome. The main clinical findings include dyspnea, congestive heart failure, PH, and large V waves on pulmonary capillary wedge pressure (PCWP) or LA pressure tracings in the absence of mitral regurgitation.