Catheter ablation vs advanced therapy for patients with severe heart failure and ventricular electrical storm.

BACKGROUND: Current data on outcomes of an initial strategy of catheter ablation vs advanced therapy in patients with severe heart failure (HF) and electric storm (ES) are limited. OBJECTIVE: The purpose of this study was to evaluate the outcomes of ventricular tachycardia (VT) ablation vs left ventricular assist device (LVAD) or heart transplantation (HT) in patients with severe HF and ventricular ES. METHODS: Patients with severe HF and ES who underwent VT ablation, LVAD, or HT between 2012 and 2022 at our medical center were reviewed. Severe HF was defined as ejection fraction ≤ 35% or presence of severe restrictive, valvular, or genetic cardiomyopathy. We assessed in-hospital adverse events and 1-year outcomes between the 2 groups. RESULTS: Of the 73 patients, 43 (58.9%) underwent VT ablation and 30 (41.1%) received advanced therapy (21 HT (70%) and 9 LVAD (30%)). One-year survival was similar (76.7% vs 86.7%; log-rank, P = .308). However, 10 patients (23.3%) in the ablation group underwent HT during follow-up. After multivariable analysis, United Network for Organ Sharing status 1 or 2 according to VT criteria (hazard ratio 5.52; 95% confidence interval 1.27-24.12; P = .023) and early VT recurrence (hazard ratio 5.67; 95% confidence interval 1.68-19.09; P = .005) were associated with HT or mortality in patients who underwent VT ablation. CONCLUSION: Patients with severe HF and ES who underwent VT ablation had similar overall survival to patients who directly proceeded with advanced therapy, although rates of HT were high during follow-up. Predictors of HT or mortality after catheter ablation include United Network for Organ Sharing status 1 or 2 according to VT criteria and early VT recurrence.

Anticoagulation Alone vs Anticoagulation Plus Aspirin or DAPT Following Left Atrial Appendage Occlusion.

BACKGROUND: The prevalence of and outcomes associated with different antithrombotic strategies after left atrial appendage occlusion (LAAO) are not well described. OBJECTIVES: This study sought to evaluate patterns of antithrombotic medication strategies at discharge following LAAO with the Watchman FLX device in real-world practice and to compare the risk of adverse events among the different antithrombotic regimens. METHODS: The authors evaluated patients in the NCDR (National Cardiovascular Data Registry) LAAO Registry who underwent LAAO with the second-generation LAA closure device between 2020 and 2022. They grouped patients by mutually exclusive discharge antithrombotic strategies and compared the rates of adverse events at 45 days and 6 months using multivariable Cox proportional hazards regression. RESULTS: Among 53,878 patients undergoing successful LAAO with the second-generation LAA closure device, the most common antithrombotic discharge regimens were direct oral anticoagulant (DOAC) plus aspirin (48.3%), DOAC alone (22.6%), dual antiplatelet therapy (8.1%), warfarin plus aspirin (7.7%), and DOAC plus P2Y12 inhibitor (4.9%). In multivariate analysis, DOAC alone had a lower rate of major adverse events and major bleeding at 45 days of follow-up compared with DOAC plus aspirin (major adverse events: HR: 0.78; 95% CI: 0.68-0.91; major bleeding: HR: 0.69; 95% CI: 0.60-0.80). These differences persisted at 6 months. Warfarin without aspirin also showed lower rates of major bleeding at both time points. No differences were seen in stroke/transient ischemic attack or device-related thrombus. CONCLUSIONS: In real-world U.S. practice, discharge on DOAC alone or warfarin alone was associated with a lower rate of adverse events compared with DOAC plus aspirin.

Enhancing patient acceptance of ICD implantation through structured shared decision making: conversation is key.

BACKGROUND: Implantable cardioverter-defibrillators (ICDs) and cardiac resynchronization therapy defibrillators (CRT-D) are lifesaving treatments for patients at risk for sudden cardiac death. Effective physician-patient communication during the shared decision-making process is essential. Electrophysiologist-patient conversations were targeted to obtain objective data on the interaction, understand the conversation framework, and uncover opportunities for improved communication. METHODS: Individuals previously identified as requiring an ICD/CRT-D but declined implantation were recruited for this four-stage interview and survey-based study. Quantitative analysis of surveys and AI analysis of conversation videos was conducted to evaluate patient participant expectations, analyze feedback about the conversations with study physicians, and gauge willingness for device implantation. RESULTS: The study included 27 patients (mean age 51 years, 51.9% female) and 9 study physicians. Patients were significantly more willing to undergo ICD/CRT-D implantation after conversing with study physicians compared to their own physicians and pre-conversation surveys (mean scores: 5.0, 3.1, and 4.4 out of 7, respectively; p < 0.001). Patient participants had higher satisfaction with the study conversation, rating study physicians higher in effectiveness of explanations, responsiveness to questions, and overall quality of the conversation compared to their own physicians (all p < 0.001). CONCLUSIONS: In a cohort of patients who previously declined ICD/CRT-D implantation, patient satisfaction and willingness to undergo implantation of a guideline-directed device therapy increased significantly following a structured conversation with study physicians. Identified key elements could be integrated into user-friendly tools and educational materials to facilitate these conversations, improving patient engagement with the decision-making process and enhancing informed acceptance of indicated device therapies.

Outcomes With the WATCHMAN FLX in Everyday Clinical Practice From the NCDR Left Atrial Appendage Occlusion Registry.

BACKGROUND: PINNACLE FLX (Protection Against Embolism for Nonvalvular AF Patients: Investigational Device Evaluation of the WATCHMAN FLX LAA Closure Technology) demonstrated improved outcomes and low incidence of adverse events with the WATCHMAN FLX device in a controlled setting. The National Cardiovascular Disease Registry's Left Atrial Appendage Occlusion Registry was utilized to assess the safety and effectiveness of WATCHMAN FLX in contemporary clinical practice in the United States. METHODS: The WATCHMAN FLX Device Surveillance Post Approval Analysis Plan used data from the Left Atrial Appendage Occlusion registry to identify patients undergoing WATCHMAN FLX implantation between August 2020 and September 2022. The key safety end point was defined as all-cause death, ischemic stroke, systemic embolism, or device or procedure-related events requiring open cardiac surgery or major endovascular intervention between device implantation and hospital discharge. Major adverse events were reported at hospital discharge, 45 days, and 1 year. RESULTS: Among 97 185 patients in the Left Atrial Appendage Occlusion registry undergoing WATCHMAN FLX, successful implantation occurred in 97.5% (n=94 784) of patients. The key safety end point occurred in 0.45% of patients. At 45 days post-procedure, all-cause death occurred in 0.81% patients, ischemic stroke in 0.23%, major bleeding in 3.1%, pericardial effusion requiring intervention in 0.50%, device-related thrombus in 0.44%, and device embolism in 0.04% patients. No peri-device leak was observed in 83.1% of patients at 45 days. At 1 year, the rate of all-cause death was 8.2%, the rate of any stroke was 1.5% (ischemic stroke, 1.2%), and major bleeding occurred in 6.4% of patients. CONCLUSIONS: In a large contemporary cohort of patients with the WATCHMAN FLX device, the rates of implant success and clinical outcomes through 1 year were comparable with the PINNACLE FLX study, demonstrating that favorable outcomes achieved in the pivotal approval study can be replicated in routine clinical practice.

Infra-Hisian Conduction Disturbance and Alternating Left Anterior/Posterior Fascicular Block.

We present an unusual case of alternating left anterior and left posterior fascicular block. Given the known risk for progression to complete atrioventricular block with alternating right bundle and left bundle branch block, we performed an electrophysiological study. Findings were consistent with infra-Hisian disease, and the patient underwent pacemaker implantation.

Impact of artificial intelligence arrhythmia mapping on time to first ablation, procedure duration, and fluoroscopy use.

INTRODUCTION: Artificial intelligence (AI) ECG arrhythmia mapping provides arrhythmia source localization using 12-lead ECG data; whether this information impacts procedural efficiency is unknown. We performed a retrospective, case-control study to evaluate the hypothesis that AI ECG mapping may reduce time to ablation, procedural duration, and fluoroscopy. MATERIALS AND METHODS: Cases in which system output was used were retrospectively enrolled according to IRB-approved protocols at each site. Matched control cases were enrolled in reverse chronological order beginning on the last day for which the technology was unavailable. Controls were matched based upon physician, institution, arrhythmia, and a predetermined complexity rating. Procedural metrics, fluoroscopy data, and clinical outcomes were assessed from time-stamped medical records. RESULTS: The study group consisted of 28 patients (age 65 ± 11 years, 46% female, left atrial dimension 4.1 ± 0.9 cm, LVEF 50 ± 18%) and was similar to 28 controls. The most common arrhythmia types were atrial fibrillation (n = 10), premature ventricular complexes (n = 8), and ventricular tachycardia (n = 6). Use of the system was associated with a 19.0% reduction in time to ablation (133 ± 48 vs. 165 ± 49 min, p = 0.02), a 22.6% reduction in procedure duration (233 ± 51 vs. 301 ± 83 min, p < 0.001), and a 43.7% reduction in fluoroscopy (18.7 ± 13.3 vs. 33.2 ± 18.0 min, p < 0.001) versus controls. At 6 months follow-up, arrhythmia-free survival was 73.5% in the study group and 63.3% in the control group (p = 0.56). CONCLUSION: Use of forward-solution AI ECG mapping is associated with reductions in time to first ablation, procedure duration, and fluoroscopy without an adverse impact on procedure outcomes or complications.

Characterizing cardiac contractile motion for noninvasive radioablation of ventricular tachycardia.

Background: Respiratory motion management strategies are used to minimize the effects of breathing on the precision of stereotactic ablative radiotherapy for ventricular tachycardia, but the extent of cardiac contractile motion of the human heart has not been systematically explored. Objective: We aim to assess the magnitude of cardiac contractile motion between different directions and locations in the heart. Methods: Patients with intracardiac leads or valves who underwent 4-dimensional cardiac computed tomography (CT) prior to a catheter ablation procedure for atrial or ventricular arrhythmias at 2 medical centers were studied retrospectively. The displacement of transvenous right atrial appendage, right ventricular (RV) implantable cardioverter-defibrillator, coronary sinus lead tips, and prosthetic cardiac devices across the cardiac cycle were measured in orthogonal 3-dimensional views on a maximal-intensity projection CT reconstruction. Results: A total of 31 preablation cardiac 4-dimensional cardiac CT scans were analyzed. The LV lead tip had significantly greater motion compared with the RV lead in the anterior-posterior direction (6.0 ± 2.2 mm vs 3.8 ± 1.7 mm; P = .01) and superior-inferior direction (4.4 ± 2.9 mm vs 3.5 ± 2.0 mm; P = .049). The prosthetic aortic valves had the least movement of all fiducials, specifically compared with the RV lead tip in the left-right direction (3.2 ± 1.2 mm vs 6.1 ± 3.8 mm, P = .04) and the LV lead tip in the anterior-posterior direction (3.8 ± 1.7 mm vs 6.0 ± 2.2 mm, P = .03). Conclusion: The degree of cardiac contractile motion varies significantly (1 mm to 15.2 mm) across different locations in the heart. The effect of contractile motion on the precision of radiotherapy should be assessed on a patient-specific basis.

Pulsed Field Ablation Index-Guided Ablation for Lesion Formation: Impact of Contact Force and Number of Applications in the Ventricular Model.

BACKGROUND: The effect of contact force (CF) on lesion formation is not clear during pulsed field ablation (PFA). The aim of this study was to evaluate the impact of CF, PFA, and their interplay through the PFA index (PF index) formula on the ventricular lesion size in swine. METHODS: PFA was delivered through the CF-sensing OMNYPULSE catheter. Predefined PFA applications (×3, ×6, ×9, and ×12) were delivered maintaining low (5-25 g), high (26-50 g), and very high (51-80 g) CFs. First, PFA lesions were evaluated on necropsy in 11 swine to investigate the impact of CF/PFA-and their integration in the PF index equation-on lesion size (study characterization). Then, 3 different PF index thresholds-300, 450, and 600-were tested in 6 swine to appraise the PF index accuracy to predict the ventricular lesion depth (study validation). RESULTS: In the study characterization data set, 111 PFA lesions were analyzed. CF was 32±17 g. The average lesion depth and width were 3.5±1.2 and 12.0±3.5 mm, respectively. More than CF and PFA dose alone, it was their combined effect to impact lesion depth through an asymptotically increasing relationship. Likewise, not only was the PF index related to lesion depth in the study validation data set (r2=0.66; P<0.001) but it also provided a prediction accuracy of the observed depth of ±2 mm in 69/73 lesions (95%). CONCLUSIONS: CF and PFA applications play a key role in lesion formation during PFA. Further studies are required to evaluate the best PFA ablation settings to achieve transmural lesions.

Predicting Major Adverse Events in Patients Undergoing Transcatheter Left Atrial Appendage Occlusion.

BACKGROUND: The National Cardiovascular Data Registry Left Atrial Appendage Occlusion Registry (LAAO) includes the vast majority of transcatheter LAAO procedures performed in the United States. The objective of this study was to develop a model predicting adverse events among patients undergoing LAAO with Watchman FLX. METHODS: Data from 41 001 LAAO procedures with Watchman FLX from July 2020 to September 2021 were used to develop and validate a model predicting in-hospital major adverse events. Randomly selected development (70%, n=28 530) and validation (30%, n=12 471) cohorts were analyzed with 1000 bootstrapped samples, using forward stepwise logistic regression to create the final model. A simplified bedside risk score was also developed using this model. RESULTS: Increased age, female sex, low preprocedure hemoglobin, no prior attempt at atrial fibrillation termination, and increased fall risk most strongly predicted in-hospital major adverse events and were included in the final model along with other clinically relevant variables. The median in-hospital risk-standardized adverse event rate was 1.50% (range, 1.03%-2.84%; interquartile range, 1.42%-1.64%). The model demonstrated moderate discrimination (development C-index, 0.67 [95% CI, 0.65-0.70] and validation C-index, 0.66 [95% CI, 0.62-0.70]) with good calibration. The simplified risk score was well calibrated with risk of in-hospital major adverse events ranging from 0.26% to 3.90% for a score of 0 to 8, respectively. CONCLUSIONS: A transcatheter LAAO risk model using National Cardiovascular Data Registry and LAAO Registry data can predict in-hospital major adverse events, demonstrated consistency across hospitals and can be used for quality improvement efforts. A simple bedside risk score was similarly predictive and may inform shared decision-making.

Pulsed field ablation versus thermal energy ablation for atrial fibrillation: a systematic review and meta-analysis of procedural efficiency, safety, and efficacy.

BACKGROUND: Pulsed field ablation (PFA) induces cell death through electroporation using ultrarapid electrical pulses. We sought to compare the procedural efficiency characteristics, safety, and efficacy of ablation of atrial fibrillation (AF) using PFA compared with thermal energy ablation. METHODS: We performed an extensive literature search and systematic review of studies that compared ablation of AF with PFA versus thermal energy sources. Risk ratio (RR) 95% confidence intervals (CI) were measured for dichotomous variables and mean difference (MD) 95% CI were measured for continuous variables, where RR < 1 and MD < 0 favor the PFA group. RESULTS: We included 6 comparative studies for a total of 1012 patients who underwent ablation of AF: 43.6% with PFA (n = 441) and 56.4% (n = 571) with thermal energy sources. There were significantly shorter procedures times with PFA despite a protocolized 20-min dwell time (MD - 21.95, 95% CI - 33.77, - 10.14, p = 0.0003), but with significantly longer fluroscopy time (MD 5.71, 95% CI 1.13, 10.30, p = 0.01). There were no statistically significant differences in periprocedural complications (RR 1.20, 95% CI 0.59-2.44) or recurrence of atrial tachyarrhythmias (RR 0.64, 95% CI 0.31, 1.34) between the PFA and thermal ablation cohorts. CONCLUSIONS: Based on the results of this meta-analysis, PFA was associated with shorter procedural times and longer fluoroscopy times, but no difference in periprocedural complications or rates of recurrent AF when compared to ablation with thermal energy sources. However, larger randomized control trials are needed.

Frailty and associated outcomes in patients undergoing percutaneous left atrial appendage occlusion: findings from the NCDR LAAO registry.

BACKGROUND: Frailty is associated with significant morbidity and mortality and may have clinical implications in an advanced age population with atrial fibrillation undergoing left atrial appendage occlusion (LAAO). We sought to develop a novel frailty scale to predict worse outcomes in patients undergoing LAAO. METHODS: Patients in the NCDR LAAO Registry between 2016 and 2021 receiving percutaneous LAAO devices were categorized as non-frail (0 points), pre-frail (1-3 points), or frail (4-5 points) based on a 5-point scale representing multiple domains of frailty: hemoglobin <13.0 g/dL in male, <12.0 g/dL in female; creatinine ≥1.2 mg/dL; albumin <3.5 g/dL; body mass index <20 kg/m2; and increased risk of falls. RESULTS: Of 57,728 patients, 44,360 (76.8%) were pre-frail and 7693 (13.3%) were frail. Compared to non-frail, pre-frail and frail patients were older, had a higher burden of co-morbidities, and more disability based on the Modified Rankin Scale. Compared to non-frail patients after adjustment, frail patients were at higher risk of in-hospital major complication (OR 1.29, 95% 1.02-1.62, p = 0.01), any complication (OR 1.29, 95% CI 1.09-1.52, p = 0.0005), and death (OR 5.79, 95% CI 1.75-19.17, p = 0.001), while no difference was observed in pre-frail patients. At 45-day follow-up, there was no difference in the risk of complications in frail patients as compared to non-frail, although mortality was significantly higher (OR 3.01, 95% CI 1.97-4.85, p < 0.0001). CONCLUSION: A simple and practical frailty scale accurately predicts adverse events in patients undergoing LAAO. The 13% of patients considered frail were at significantly higher risk of in-hospital adverse events and 45-day mortality.

Stroke Prevention in Atrial Fibrillation: Our Current Failures and Required Research.

Nonvalvular atrial fibrillation is a common rhythm disorder of middle-aged to older adults that can cause ischemic strokes and systemic embolism. Lifelong use of oral anticoagulants reduces the risk of these ischemic events but increases the risk of major and clinically relevant hemorrhages. These medications also require strict compliance for efficacy, and they have nontrivial failure rates in higher-risk patients. Left atrial appendage closure is a nonpharmacological method to prevent ischemic strokes in atrial fibrillation without the need for lifelong anticoagulant use, but this procedure has the potential for complications and residual embolic events. This workshop of the Roundtable of Academia and Industry for Stroke Prevention discussed future research needed to further decrease the ischemic and hemorrhagic risks among patients with atrial fibrillation. A direct thrombin inhibitor, factor Xa inhibitors, and left atrial appendage closure are FDA-approved approaches whereas factor XIa inhibitors are currently being studied in phase 3 randomized controlled trials for stroke prevention. The benefits, risks, and shortcomings of these treatments and future research required in different high-risk patient populations are reviewed in this consensus statement.

DAPT Is Comparable to OAC Following LAAC With WATCHMAN FLX: A National Registry Analysis.

BACKGROUND: Left atrial appendage occlusion (LAAO) is an approved alternative for stroke prevention in atrial fibrillation for patients with an "appropriate rationale" to avoid long-term oral anticoagulation (OAC). Many patients undergoing LAAO are at high risk of bleeding. OBJECTIVES: This study sought to investigate whether dual antiplatelet therapy (DAPT) is a safe alternative to OAC (direct oral anticoagulation [DOAC] or warfarin) with aspirin after LAAO. METHODS: Using National Cardiovascular Data Registry LAAO registry data, patients undergoing Watchman FLX (Boston Scientific) implantation (August 5, 2020-September 30, 2021) were included in 1:1 propensity-matched analyses comparing discharge medication regimens (DAPT, DOAC/aspirin, or warfarin/aspirin). A composite endpoint (death, stroke, major bleeding, and systemic embolism), its components, and device-related thrombus between discharge and 45 days were evaluated. RESULTS: In 49,968 patients implanted with the Watchman FLX during the study period, the mean age was 77 years, and 40% were women. Postimplant DOAC/aspirin was prescribed in 24,497 patients, warfarin/aspirin in 3,913, and DAPT in 4,155. DAPT patients had more comorbid conditions than patients receiving OAC/aspirin. After propensity score matching, the 45-day composite endpoint rates were similar among the groups (DAPT = 3.44% vs DOAC/aspirin: 4.06%; P = 0.13 and DAPT = 3.23% vs warfarin/aspirin: 3.08%; P = 0.75). Death, stroke, and device-related thrombus were also similar; major bleeding was slightly increased in DOAC/aspirin patients (DAPT = 2.48% vs DOAC/aspirin = 3.25%; P = 0.04 and DAPT = 2.25% vs warfarin/aspirin = 2.22%; P = 0.93). CONCLUSIONS: In a large registry, DAPT had a similar safety profile compared with current Food and Drug Administration-approved postimplant drug regimens of OAC with aspirin following LAAO with the Watchman FLX. Shared decision making for nonpharmacologic stroke prevention should include a discussion of postprocedure medical therapy options.

Safety and acute efficacy of catheter ablation for atrial fibrillation with pulsed field ablation vs thermal energy ablation: A meta-analysis of single proportions.

Background: Pulsed field ablation (PFA) has emerged as a novel energy source for the ablation of atrial fibrillation (AF) using ultrarapid electrical pulses to induce cell death via electroporation. Objective: The purpose of this study was to compare the safety and acute efficacy of ablation for AF with PFA vs thermal energy sources. Methods: We performed an extensive literature search and systematic review of studies that evaluated the safety and efficacy of ablation for AF with PFA and compared them to landmark clinical trials for ablation of AF with thermal energy sources. Freeman-Tukey double arcsine transformation was used to establish variance of raw proportions followed by the inverse with the random-effects model to combine the transformed proportions and generate the pooled prevalence and 95% confidence interval (CI). Results: We included 24 studies for a total of 5203 patients who underwent AF ablation. Among these patients, 54.6% (n = 2842) underwent PFA and 45.4% (n = 2361) underwent thermal ablation. There were significantly fewer periprocedural complications in the PFA group (2.05%; 95% CI 0.94-3.46) compared to the thermal ablation group (7.75%; 95% CI 5.40-10.47) (P = .001). When comparing AF recurrence up to 1 year, there was a statistically insignificant trend toward a lower prevalence of recurrence in the PFA group (14.24%; 95% CI 6.97-23.35) compared to the thermal ablation group (25.98%; 95% CI 15.75-37.68) (P = .132). Conclusion: Based on the results of this meta-analysis, PFA was associated with lower rates of periprocedural complications and similar rates of acute procedural success and recurrent AF with up to 1 year of follow-up compared to ablation with thermal energy sources.