Srivathsan, Komandoor

ABSTRACT Background Pulsed field ablation (PFA) is an emerging non‐thermal ablation modality with proven safety in atrial arrhythmia ablation. However, data on its performance for ventricular arrhythmias (VA) remain limited. Objective To evaluate the feasibility, safety, and efficacy of PFA for complex VA in a multicenter real‐world US registry. Methods This retrospective study included consecutive patients undergoing PFA for ventricular tachycardia (VT) or premature ventricular contractions (PVCs) at three Mayo Clinic centers (April 2024 to July 2025). The primary feasibility outcome was the successful delivery of PFA lesions to the intended target substrate. Primary efficacy outcomes included acute procedural success; sustained VT recurrence requiring implantable cardioverter‐defibrillator (ICD) shocks or multiple antitachycardia pacing therapies; and ≥ 80% reduction in PVC burden. Safety outcomes included procedural complications, valvular function, thromboembolic events, renal function, and conduction disturbances. Results Twenty‐six patients were included (13 PVC, 13 VT). Acute success was achieved in all VT ablations (69.2% complete; 30.8% partial) and in 92.3% of PVC ablations. Complications occurred in 11.5% of patients (transient LBBB [ n = 1] and vascular complications [ n = 2]). No thromboembolic events, intracardiac thrombus, or acute kidney injury were observed. Lesions near the mitral valve apparatus did not worsen mitral regurgitation, including in patients with pre‐existing valve disease. After a median follow‐up of 365 days, one patient experienced VT recurrence requiring ICD shocks. Estimated recurrence‐free survival after VT ablation was 61.5% at 12 months; 58.3% of PVC patients achieved ≥ 80% burden reduction. Conclusion PFA for VA appears feasible and acutely effective, with a low rate of procedure‐related complications. While acute success was high, long‐term outcomes were acceptable for VT ablation and relatively modest for PVC ablation, highlighting the need for continued refinement of technology and energy‐delivery strategies. Larger prospective studies are warranted.

Abstract Aims Randomized trials comparing percutaneous left atrial appendage occlusion (LAAO) with oral anticoagulation (OAC) for stroke prevention in patients with atrial fibrillation have yielded conflicting results across device generations and anticoagulant eras. This Bayesian meta-analysis of randomized trials aimed to compare LAAO vs. OAC for stroke or systemic embolism (SSE) and non-procedural clinically relevant bleeding (CRB). Methods and results We conducted a systematic search across five databases (PubMed, Embase, Scopus, Web of Science, and Cochrane CENTRAL) to identify randomized trials of LAAO vs. OAC. Primary outcomes of stroke or systemic embolism, non-procedural CRB and clinical benefit composite were estimated using a Bayesian hierarchical random effects model and findings confirmed across robust sensitivity and subgroup analyses. Posterior probabilities for superiority, non-inferiority and equivalence were estimated using clinically meaningful margins. Six randomized trials including 7004 participants in the intention-to-treat groups, were analysed. LAAO was not associated with lower SSE vs. OAC (pooled RR, 1.11; 95% CrI, 0.80–1.49), with a 74.6% posterior probability of favouring OAC. The posterior probability of crossing non-inferiority was P(HR < 1.4) of 89%. In contrast, LAAO reduced non-procedural CRB (pooled RR, 0.59; 95% CrI, 0.45–0.78). The net clinical benefit composite, pooling contemporary trials, demonstrated a pooled RR of 0.90 (95% CrI 0.51–1.50), with P(RR < 1) of 76%, with substantial heterogeneity for this outcome. Conclusion This Bayesian meta-analysis found no clear evidence supporting clinically meaningful non-inferiority of LAAO over OAC for stroke prevention. Despite reduced non-procedural bleeding, LAAO did not demonstrate a similar reduction in major bleeding.

ABSTRACT Patients requiring permanent pacing after tricuspid valve intervention present challenges due to the need to cross tricuspid valve prostheses. We report three cases of successful dual coronary sinus (CS) lead implantation for biventricular pacing following a range of tricuspid interventions—surgical tricuspid annuloplasty, transcatheter edge‐to‐edge repair, and transcatheter tricuspid valve replacement. The approach avoided tricuspid valve traversal, was technically feasible and resulted in satisfactory pacing performance without procedural complications. Dual CS lead configurations were individualized based on CS anatomy and pacing characteristics. The degree of QRS narrowing achieved varied according to lead location and ventricular activation patterns, highlighting the importance of individualized lead placement strategies and device programming. Dual CS lead pacing may represent a viable alternative for biventricular pacing in selected patients with prior tricuspid valve interventions. Larger studies are needed to evaluate long‐term outcomes and define the optimal role of this approach among available pacing strategies in this patient population.

Abstract Background/Introduction Atrial fibrillation (AF) is a common finding in patients with wild-type TTR amyloidosis. AF ablation represents a cornerstone of rhythm control in this population; however, the role of pulsed field ablation (PFA) remains unclear. Purpose This study aimed to describe the safety and efficacy of PFA for the treatment of atrial fibrillation in patients with wild-type TTR amyloidosis. Methods We conducted a prospective data collection of consecutive patients who underwent PFA for AF and had a confirmed diagnosis of wild-type TTR amyloidosis. The study included three centres within a major US health system. All procedures were performed between May 2024 and May 2025. A standardised follow-up strategy was applied, including 48-hour Holter monitoring between 90 and 180 days after ablation. The primary safety endpoint was the occurrence of procedural complications. The primary efficacy outcomes were acute procedural success and AF-free survival at six months after a blanking period of 30 days. AF recurrence was defined as any electrocardiographically documented episode lasting more than 30 seconds. Results A total of 13 patients were included in the study. The mean age was 72.6 ± 4.8 years, and all patients were male. Three patients (23.1%) underwent an index "redo" ablation. Seven patients (53.8%) had paroxysmal atrial fibrillation (AF). The median CHA2DS2-VASc score was 3 [2, 4.5], with a mean ejection fraction of 50.4 ± 14.8% and a mean left atrial volume index of 47.6 ± 15.7 mL/m². Eleven patients underwent PFA with the pentaspline Farawave catheter, and two with the focal Sphere-9 catheter. Additional extra-pulmonary vein lesions were performed in 11 patients, including posterior wall ablation in ten patients, cavotricuspid isthmus ablation in five, and mitral isthmus ablation in four patients. The primary endpoint occurred in one patient (7.7%) who developed acute respiratory failure complicated by pulseless electrical activity (PEA) arrest. The patient was successfully resuscitated but required prolonged hospital admission. All patients achieved acute pulmonary vein isolation, and six-month atrial fibrillation-free survival was 54.4%. Conclusion In this multicentre experience, pulsed field ablation (PFA) in patients with cardiac amyloidosis was feasible and acutely safe; however, the mid-term efficacy was suboptimal, with a relatively low six-month arrhythmia-free survival despite complete acute pulmonary vein isolation. These findings suggest that the current PFA strategies may not provide durable rhythm control in this population, underscoring the need for tailored ablation approaches and further research to improve long-term outcomes in patients with cardiac amyloidosis and atrial fibrillation.Figure 1

BACKGROUND: Catheter ablation for atrial fibrillation is a widely used rhythm-control strategy, yet its role in reducing thromboembolic risk and enabling oral anticoagulation (OAC) discontinuation remains uncertain. This meta-analysis aims to comprehensively synthesize and evaluate randomized controlled trial evidence supporting long-term antithrombotic strategies in patients with atrial fibrillation undergoing catheter ablation. METHODS: A systematic literature search was performed in MEDLINE/PubMed, Embase, and the Cochrane Central Register of Controlled Trials to identify randomized controlled trials evaluating antithrombotic strategies after catheter ablation for atrial fibrillation. The primary outcome was ischemic stroke. A frequentist network meta-analysis comparing reported treatment arms, along with a pooled incidence meta-analysis for outcomes of interest, was conducted. RESULTS: Four randomized controlled trials, including 3924 patients, met the inclusion criteria. Three trials compared long-term OAC continuation versus OAC discontinuation, and 1 compared OAC continuation with left atrial appendage occlusion after catheter ablation. No significant differences in stroke incidence were observed when comparing OAC or left atrial appendage occlusion with no antithrombotic therapy (incidence rate ratio, 0.90 [95% CI, 0.02–33.85]; P =0.95; incidence rate ratio, 0.79 [95% CI, 0.00–241.01]; P =0.94, respectively). Among patients who discontinued antithrombotic therapy without undergoing left atrial appendage occlusion (n=1161), with 2864 cumulative person-years of follow-up, the pooled incidence of stroke was 0.23 events per 100 person-years (95% CI, 0.02–2.43; I 2 =0%). CONCLUSIONS: This analysis reinforces that, across randomized data, the incidence of thromboembolic events in patients who discontinued OAC after successful ablation remained low. However, the evaluation of net clinical benefit is limited by the low number of events across all treatment arms, underscoring the need for larger studies with prolonged follow-up to further validate the safety of this strategy, particularly in higher-risk populations.

Abstract Aims The clinical significance of early recurrences during the blanking period following pulmonary vein isolation (PVI) remains uncertain, particularly after pulsed field ablation (PFA). This study aimed to evaluate the prognostic impact of early recurrences at 30-, 60-, and 90-day thresholds on outcomes following PFA for atrial fibrillation (AF). Methods and results Consecutive patients who underwent PFA for AF across multiple centres within the Mayo Clinic health system were included. The primary endpoint was AF-free survival. Kaplan–Meier and multivariate Cox regression analyses were performed to compare outcomes between patients with and without early recurrences using 30-, 60-, and 90-day thresholds. A total of 1162 patients were included. The estimated AF-free survival at 1 year was 70%. Early recurrences within 30-, 60-, and 90-days post-ablation were significantly associated with late recurrences beyond 90 days (hazard ratio [HR] 5.9, 95% confidence interval [CI] 4.4–7.9, P < 0.01; HR 6.6, 95% CI: 5.0–8.6, P < 0.01; and HR 9.1, 95% CI: 7.0–11.7, P < 0.01, respectively). These findings remained significant among patients undergoing continuous rhythm monitoring. Early recurrences within 30 days in this subgroup were significantly associated with a 1-year AF burden >1% or the need for repeat AF ablation (odds ratio 25.0, 95% CI: 6.6–126.8, P < 0.01). Conclusion Early recurrences following PFA are strongly predictive of long-term arrhythmia recurrence and are unlikely to represent transient inflammatory phenomena. Accordingly, the applicability of the conventional blanking interval after PFA should be reconsidered.

Abstract Background Emerging evidence suggests that premature ventricular contractions (PVCs) may influence atrial electrophysiology and remodeling, potentially leading to higher rates of atrial fibrillation (AF) recurrence. However, existing data is limited to small-scale studies. Therefore, we conducted a retrospective study to evaluate the potential association between PVCs and AF ablation outcomes, which may suggest the need for more aggressive management of ventricular ectopy in this population. Objective This study aims to assess the 5-year outcomes of catheter ablation for AF in patients with and without a diagnosis of PVCs. Methods Using the TriNetX Analytics Research Network, we included patients aged ≥ 18 years who underwent AF catheter between January 1, 2014, and January 1, 2020. Patients were further categorized into two groups based on the presence of a diagnosis of PVCs. Propensity score matching (PSM) was performed using patient demographics, left ventricular ejection fraction (LVEF), cardiac comorbidities, and medications. Study outcomes included all-cause mortality & hospitalization, acute heart failure (HF), and rhythm control interventions during a 5-year follow-up. Results A total of 15,987 patients with PVCs and 40,605 patients without PVCs were identified. After PSM, 15,152 patients from each group were included for further analysis. Compared to control group, patients with PVCs had significantly higher odds of all-cause mortality (odds ratio [OR], 1.138; 95% confidence interval [CI], 1.034–1.253), all-cause hospitalization (OR, 1.300; 95% CI, 1.243–1.360), acute heart failure (HF) (OR, 1.223; 95% CI, 1.162–1.287), and cardiogenic shock (OR, 2.059; 95% CI, 1.751–2.420) following catheter ablation for AF at 5-year follow-up. Additionally, higher odds of AF requiring cardioversion (OR, 1.135; 95% CI, 1.074–1.199) or repeated ablation (OR, 1.164; 95% CI, 1.085–1.249) were observed in the PVCs group. Conclusion Premature ventricular contractions were associated with poorer clinical outcomes and a higher odds of requiring additional rhythm control intervention following catheter ablation for AF. These findings suggest that PVCs may be a marker for worse outcomes after AF ablation.

BACKGROUND: Cavotricuspid isthmus (CTI) ablation is frequently performed either as a standalone procedure or in combination with pulmonary vein isolation. With the rapid adoption of pulsed field ablation for atrial fibrillation, it is essential to delineate the utility of this modality in treating CTI-dependent atrial flutter (AFL). This study aims to evaluate the procedural and clinical outcomes of CTI ablation using pulsed field energy. METHODS: We conducted a retrospective analysis of consecutive patients who underwent pulsed field ablation for CTI-dependent AFL between January 2024 and March 2025. The primary end points were acute procedural success, periprocedural complications, and CTI-dependent AFL recurrence during follow-up. RESULTS: A total of 132 patients underwent CTI nonthermal ablation. The median age was 69.5 years, and 27.3% were female. The Farawave catheter was used in 93.9% of cases, PulseSelect in 4.5%, and Sphere-9 in 1.5%. Acute block was achieved in 99.2% of patients, although 8 required adjunctive radiofrequency ablation to complete the line. Periprocedural complications included transient ST-segment elevation in 2 patients and transient conduction disturbances in 3. During a median follow-up of 114 days (n=131), 5 patients (3.8%) experienced recurrence of typical AFL. The 6-month typical AFL-free survival estimate was 93.6%. CONCLUSIONS: Pulsed field ablation appears to be a feasible and effective strategy for CTI-dependent AFL. However, anatomic variability may limit its universal applicability with current catheter designs. Although acute procedural success is high, the long-term durability of the CTI block and its comparative efficacy versus conventional thermal ablation remain areas requiring further investigation.

ABSTRACT Background While radiofrequency ablation (RFA) and cryoablation (CBA) are established treatments for atrial fibrillation (AF), pulsed field ablation (PFA) offers potential benefits. This study compares PFA's procedural outcomes with RFA and CBA. Methods A PRISMA‐guided systematic review searched PubMed, Cochrane, Embase, and Scopus through September 2024. Studies comparing PFA to RFA or CBA in paroxysmal and persistent AF were included. Results From 1413 titles, 28 studies (7944 patients, 4–13 months follow‐up) met inclusion criteria. PFA showed lower recurrence versus RFA (RR = 0.85, p < 0.05) and CBA (RR = 0.81, p < 0.01). Procedure times were shorter versus RFA (‐46.39 min, p < 0.01) and CBA (‐9.26 min, p < 0.01). PFA had fewer complications than CBA (RR = 0.45, p < 0.01) and thermal ablation (RR = 0.55, p < 0.01), with similar rates to RFA (RR = 0.81, p = 0.25). Fluoroscopy times were higher. Conclusion Promising results with PFA suggest it as a viable alternative to thermal ablation.