Faculty Bibliography

BACKGROUND/UNASSIGNED:Favorable clinical outcomes are difficult to achieve in long-standing persistent atrial fibrillation (LSPAF) with catheter ablation (CA). The CONVERGE (Convergence of Epicardial and Endocardial Ablation for the Treatment of Symptomatic Persistent Atrial FIbrillation) trial evaluated the effectiveness of hybrid convergent (HC) ablation vs endocardial CA. OBJECTIVE/UNASSIGNED:The study sought to evaluate the safety and effectiveness of HC vs CA in the LSPAF subgroup from the CONVERGE trial. METHODS/UNASSIGNED:The CONVERGE trial was a prospective, multicenter, randomized trial that enrolled 153 patients at 27 sites. A post hoc analysis was performed on LSPAF patients. The primary effectiveness was freedom from atrial arrhythmias off new or increased dose of previously failed or intolerant antiarrhythmic drugs (AADs) through 12 months. The primary safety endpoint was major adverse event incidence through 30 days with HC. Key secondary effectiveness measures included (1) percent of patients achieving ≥90% AF burden reduction vs baseline and (2) AF freedom. RESULTS/UNASSIGNED:.038). Three (7.9%) major adverse events occurred within 30 days of HC. CONCLUSION/UNASSIGNED:Post hoc analysis demonstrated effectiveness and acceptable safety of HC compared with CA in LSPAF.

BACKGROUND/UNASSIGNED:Pulmonary vein isolation (PVI) ablation is a standard therapy for paroxysmal atrial fibrillation (PAF). Lesion Index (LSI) is a metric to guide radiofrequency (RF) ablation using the TactiCath Ablation Catheter, Sensor Enabled with the EnSite Cardiac Mapping System (Abbott). OBJECTIVE/UNASSIGNED:This study (NCT-03906461) was designed to capture best practices using LSI-guided catheter ablation to treat PAF subjects in a real-world setting. METHODS/UNASSIGNED:This prospective single-arm observational study enrolled 143 PAF subjects in the United States, Europe, and Japan undergoing de novo PVI with RF ablation. PVI lesions were assigned to 10 anatomically defined segments. Mean LSIs achieved for all lesions were analyzed. Follow-up was conducted between 3-6 months and 12 months after the procedure. RESULTS/UNASSIGNED:Pulmonary veins were isolated in all subjects. The mean achieved LSI was 4.9, with lower values in Europe (4.4) and Japan (4.5) than the United States (5.5). First-pass success, defined as no gaps requiring touch-up ablation after 20 minutes post isolation, was achieved in 76.2% of subjects. Use of high LSI (≥5) resulted in shorter procedure, RF, and fluoroscopy times and fewer touch-up ablations compared to low LSI (<5). At 12 months, 99.3% of subjects were free from procedure- or device-related serious adverse events and 95.7% (112/117) (35.0% on antiarrhythmic drugs) were free from recurrence and/or a repeat ablation procedure for atrial fibrillation / atrial flutter / atrial tachycardia. CONCLUSION/UNASSIGNED:LSI-guided ablation strategies proved safe and effective despite differences in LSI workflows. Use of high LSI values resulted in shorter procedure, RF, and fluoroscopy times and fewer touch-up ablations compared to low LSI.

BACKGROUND/UNASSIGNED:Hybrid Convergent ablation for atrial fibrillation (AF) combines minimally invasive surgical (epicardial) and catheter (endocardial) ablation. The procedural goal is to achieve more extensive, enduring ablation of AF substrate around the pulmonary veins, posterior wall, and vestibule of the posterior wall left atrium. OBJECTIVE/UNASSIGNED:To perform a systematic review and meta-analysis on safety and effectiveness of contemporary Hybrid Convergent procedures. METHODS/UNASSIGNED:PubMed, Embase, and manual searches identified primary research articles on Hybrid Convergent. Inclusion criteria focused on contemporary practices (epicardial ablation device and lesions). Clinical outcomes at 1 year or later follow-up, patient population, procedural details, and major adverse events (MAE) were recorded. RESULTS/UNASSIGNED:Of 249 records, 6 studies (5 observational, 1 randomized controlled trial) including 551 patients were included. Endocardial energy sources included radiofrequency and cryoballoon. Hybrid Convergent ablation was mostly performed in patients with drug-refractory persistent and longstanding persistent AF. Mean preprocedural AF duration ranged between 2 and 5.1 years. Most patients (∼92%) underwent Hybrid Convergent in a single hospitalization. At 1 year follow-up or later, 69% (95% confidence interval [CI]: 61%-78%, n = 523) were free from atrial arrhythmias and 50% (95% CI: 42%-58%, n = 343) were free from atrial arrhythmias off antiarrhythmic drugs. Thirty-day MAE rate was 6% (95% CI: 3%-8%, n = 551). CONCLUSION/UNASSIGNED:Hybrid Convergent ablation is an effective ablation strategy for persistent and longstanding persistent AF. Contemporary procedural approaches and published strategies aim to mitigate complications reported in early experience and address delayed inflammatory effusions.

Mitral valve prolapse (MVP) is a well-studied, mostly benign, phenomenon; however, arrhythmic mitral valve prolapse (AMVP) is a rare subtype that can precipitate sudden cardiac death (SCD). Herein, we present a case of a young female with sudden cardiac arrest. Extensive multimodality imaging and follow-up helped establish the diagnosis of AMVP.

The absence of strategies to consistently and effectively address nonparoxysmal atrial fibrillation by nonpharmacological interventions has represented a long-standing treatment gap. A combined epicardial/endocardial ablation strategy, the hybrid Convergent procedure, was developed in response to this clinical need. A subxiphoid incision is used to access the pericardial space facilitating an epicardial ablation directed at isolation of the posterior wall of the left atrium. This is followed by an endocardial ablation to complete isolation of the pulmonary veins and for additional ablation as needed. Experience gained with the hybrid Convergent procedure during the last decade has led to the development and adoption of strategies to optimize the technique and mitigate risks. Additionally, a surgical and electrophysiology "team" approach including comprehensive training is believed critical to successfully develop the hybrid Convergent program. A recently completed randomized clinical trial indicated that this ablation strategy is superior to an endocardial-only approach for patients with persistent atrial fibrillation. In this review, we propose and describe best practice guidelines for hybrid Convergent ablation on the basis of a combination of published data, author consensus, and expert opinion. A summary of clinical outcomes, emerging evidence, and future perspectives is also given.

This study sought to determine (1) whether the use of a narrow border-zone voltage of 0.1 to 0.25 mV predicts the ventricular tachycardia (VT) exit site better than when using the conventional 0.5 to 1.5 mV window and (2) the feasibility of utilizing the Rhythmia mapping system (Boston Scientific, Natick, MA, USA) to map hemodynamically unstable VT without hemodynamic support. The Ablation of ischemic VT is challenging especially in the setting of hemodynamic instability, yet efficient and accurate mapping of VT and VT substrate is critical for procedural success. In this study, a total of 24 patients with ischemic cardiomyopathy and recurrent monomorphic VT underwent mapping and ablation using the Rhythmia system. Contact-force sensing ablation catheters were use in two cases. In patients with mappable VTs, the distance between the exit site and border zone was calculated for border zone-voltage windows of 0.5 to 1.5 mV and 0.1 to 0.25 mV. The percentage of LV scar for each patient was visually estimated into quartiles of scar burden in both windows. Twenty patients were inducible into VT, while 15 patients had mappable VTs for a total of 16 VTs (11 stable VTs and five unstable VTs). There were no adverse complications in patients who underwent mapping in unstable VT. The mean distance from the VT exit site to the border zone was 13.3 mm in the conventional window and 3.4 mm in the narrow window (95% confidence interval: 4.0-15.8; p = 0.003). Separately, 94% (15/16) of the VTs were mapped to the narrow border-zone voltage versus 31% (5/16) using the conventional border zone (p = 0.0006). The use of a narrow 0.1- to 0.25-mV border-zone window highlights relevant scar and constitutes a border zone where VT exit sites are frequently located. We also found that exit sites of hemodynamically unstable VTs can be identified without an increase in procedural complications using the Orion catheter (Boston Scientific, Natick, MA, USA).

The treatment of AF has evolved over the past decade with increasing use of catheter ablation in patients refractory to medical therapy. While pulmonary vein isolation using endocardial catheter ablation has been successful in paroxysmal AF, the results have been more controversial in patients with long-standing persistent AF where extrapulmonary venous foci are increasingly recognised in the initiation and maintenance of AF. Hybrid ablation is the integration of minimally invasive epicardial ablation with endocardial catheter ablation, and has been increasingly used in this population with better results. The aim of this article was to analyse and discuss the evidence for the integration of catheter and minimally invasive surgical approaches to treat AF with specific focus on convergent ablation and exclusion of the left atrial appendage using a surgically applied clip.