Surpoint algorithm for improved guidance of ablation for ventricular tachycardia (SURFIRE-VT): A pilot study.

INTRODUCTION: The utility of ablation index (AI) to guide ventricular tachycardia (VT) ablation in patients with structural heart disease is unknown. The aim of this study was to assess procedural characteristics and clinical outcomes achieved using AI-guided strategy (target value 550) or conventional non-AI-guided parameters in patients undergoing scar-related VT ablation. METHODS: Consecutive patients (n = 103) undergoing initial VT ablation at a single center from 2017 to 2022 were evaluated. Patient groups were 1:1 propensity-matched for baseline characteristics. Single lesion characteristics for all 4707 lesions in the matched cohort (n = 74) were analyzed. The impact of ablation characteristics was assessed by linear regression and clinical outcomes were evaluated by Cox proportional hazard model. RESULTS: After propensity-matching, baseline characteristics were well-balanced between AI (n = 37) and non-AI (n = 37) groups. Lesion sets were similar (scar homogenization [41% vs. 27%; p = .34], scar dechanneling [19% vs. 8%; p = .18], core isolation [5% vs. 11%; p = .4], linear and elimination late potentials/local abnormal ventricular activities [35% vs. 44%; p = .48], epicardial mapping/ablation [11% vs. 14%; p = .73]). AI-guided strategy had 21% lower procedure duration (-47.27 min, 95% confidence interval [CI] [-81.613, -12.928]; p = .008), 49% lower radiofrequency time per lesion (-13.707 s, 95% CI [-17.86, -9.555]; p < .001), 21% lower volume of fluid administered (1664 cc [1127, 2209] vs. 2126 cc [1750, 2593]; p = .005). Total radiofrequency duration (-339 s [-24%], 95%CI [-776, 62]; p = .09) and steam pops (-155.6%, 95% CI [19.8%, -330.9%]; p = .08) were nonsignificantly lower in the AI group. Acute procedural success (95% vs. 89%; p = .7) and VT recurrence (0.97, 95% CI [0.42-2.2]; p = .93) were similar for both groups. Lesion analysis (n = 4707) demonstrated a plateau in the magnitude of impedance drops once reaching an AI of 550-600. CONCLUSION: In this pilot study, an AI-guided ablation strategy for scar-related VT resulted in shorter procedure time and average radiofrequency time per lesion with similar acute procedural and intermediate-term clinical outcomes to a non-AI-guided approach utilizing traditional ablation parameters.

Definition and management of arrhythmia-induced cardiomyopathy: findings from the European Heart Rhythm Association survey.

AIMS: Arrhythmia-induced cardiomyopathy (AiCM) represents a subtype of acute heart failure (HF) in the context of sustained arrhythmia. Clear definitions and management recommendations for AiCM are lacking. The European Heart Rhythm Association Scientific Initiatives Committee (EHRA SIC) conducted a survey to explore the current definitions and management of patients with AiCM among European and non-European electrophysiologists. METHODS AND RESULTS: A 25-item online questionnaire was developed and distributed among EP specialists on the EHRA SIC website and on social media between 4 September and 5 October 2023. Of the 206 respondents, 16% were female and 61% were between 30 and 49 years old. Most of the respondents were EP specialists (81%) working at university hospitals (47%). While most participants (67%) agreed that AiCM should be defined as a left ventricular ejection fraction (LVEF) impairment after new onset of an arrhythmia, only 35% identified a specific LVEF drop to diagnose AiCM with a wide range of values (5-20% LVEF drop). Most respondents considered all available therapies: catheter ablation (93%), electrical cardioversion (83%), antiarrhythmic drugs (76%), and adjuvant HF treatment (76%). A total of 83% of respondents indicated that adjuvant HF treatment should be started at first HF diagnosis prior to antiarrhythmic treatment, and 84% agreed it should be stopped within six months after LVEF normalization. Responses for the optimal time point for the first LVEF reassessment during follow-up varied markedly (1 day-6 months after antiarrhythmic treatment). CONCLUSION: This EHRA Survey reveals varying practices regarding AiCM among physicians, highlighting a lack of consensus and heterogenous care of these patients.

Procedural and Intermediate-term Results of the Electroanatomical-guided Cardioneuroablation for the Treatment of Supra-Hisian Second- or Advanced-degree Atrioventricular Block: the PIRECNA multicentre registry.

AIMS: Prior case series showed promising results for cardioneuroablation in patients with vagally induced atrioventricular blocks (VAVBs). We aimed to examine the acute procedural characteristics and intermediate-term outcomes of electroanatomical-guided cardioneuroablation (EACNA) in patients with VAVB. METHODS AND RESULTS: This international multicentre retrospective registry included data collected from 20 centres. Patients presenting with symptomatic paroxysmal or persistent VAVB were included in the study. All patients underwent EACNA. Procedural success was defined by the acute reversal of atrioventricular blocks (AVBs) and complete abolition of atropine response. The primary outcome was occurrence of syncope and daytime second- or advanced-degree AVB on serial prolonged electrocardiogram monitoring during follow-up. A total of 130 patients underwent EACNA. Acute procedural success was achieved in 96.2% of the cases. During a median follow-up of 300 days (150, 496), the primary outcome occurred in 17/125 (14%) cases with acute procedural success (recurrence of AVB in 9 and new syncope in 8 cases). Operator experience and use of extracardiac vagal stimulation were similar for patients with and without primary outcomes. A history of atrial fibrillation, hypertension, and coronary artery disease was associated with a higher primary outcome occurrence. Only four patients with primary outcome required pacemaker placement during follow-up. CONCLUSION: This is the largest multicentre study demonstrating the feasibility of EACNA with encouraging intermediate-term outcomes in selected patients with VAVB. Studies investigating the effect on burden of daytime symptoms caused by the AVB are required to confirm these findings.

Reducing the burden of inconclusive smart device single-lead ECG tracings via a novel artificial intelligence algorithm.

Background: Multiple smart devices capable of automatically detecting atrial fibrillation (AF) based on single-lead electrocardiograms (SL-ECG) are presently available. The rate of inconclusive tracings by manufacturers' algorithms is currently too high to be clinically useful. Method: This is a prospective, observational study enrolling patients presenting to a cardiology service at a tertiary referral center. We assessed the clinical value of applying a smart device artificial intelligence (AI)-based algorithm for detecting AF from 4 commercially available smart devices (AliveCor KardiaMobile, Apple Watch 6, Fitbit Sense, and Samsung Galaxy Watch3). Patients underwent a nearly simultaneous 12-lead ECG and 4 smart device SL-ECGs. The novel AI algorithm (PulseAI, Belfast, United Kingdom) was compared with each manufacturer's algorithm. Results: We enrolled 206 patients (31% female, median age 64 years). AF was present in 60 patients (29%). Sensitivity and specificity for the detection of AF by the novel AI algorithm vs manufacturer algorithm were 88% vs 81% (P = .34) and 97% vs 77% (P < .001) for the AliveCor KardiaMobile, 86% vs 81% (P = .45) and 95% vs 83% (P < .001) for the Apple Watch 6, 91% vs 67% (P < .01) and 94% vs 82% (P < .001) for the Fitbit Sense, and 86% vs 82% (P = .63) and 94% vs 80% (P < .001) for the Samsung Galaxy Watch3, respectively. In addition, the proportion of SL-ECGs with an inconclusive diagnosis (1.2%) was significantly lower for all smart devices using the AI-based algorithm compared to manufacturer's algorithms (14%-17%), P < .001. Conclusion: A novel AI algorithm reduced the rate of inconclusive SL-ECG diagnosis massively while maintaining sensitivity and improving the specificity compared to the manufacturers' algorithms.

Biomarkers to predict improvement of left ventricular ejection fraction after atrial fibrillation ablation.

BACKGROUND: Atrial fibrillation (AF) and heart failure frequently coexist. Prediction of left ventricular ejection fraction (LVEF) recovery after catheter ablation (CA) for AF remains difficult. OBJECTIVE: The purpose of this study was to evaluate the value of biomarkers, alone and in combination with the Antwerp score, to predict LVEF recovery after CA for AF. METHODS: Patients undergoing CA for AF with depressed LVEF (<50%) were included. Plasma levels of 13 biomarkers were measured immediately before CA. Patients were categorized into "responders" and "nonresponders" in a similar fashion to the Antwerp score performance derivation and validation cohorts. The predictive power of the biomarkers alone and combined in outcome prediction was evaluated. RESULTS: A total of 208 patients with depressed LVEF were included (median age 63 years; 39-19% female; median indexed left atrial volume 42 (33-52) mL/m2; median LVEF 43 (38-46)%). At a median follow-up time of 30 (20-34) months, 161 (77%) were responders and 47 (23%) were nonresponders. Of 13 biomarkers, -4-angiopoietin 2 (ANG2), growth differentiation factor 15 (GDF15), fibroblast growth factor 23, and myosin binding protein C3-were significantly different between responders and nonresponders (P ≤ .001) and their combination could predict the end point with an area under the curve of 0.72 (95% confidence interval [CI] 0.64-0.81) overall, 0.69 (95% CI 0.59-0.78) in heart failure with mildly reduced ejection fraction, and 0.88 (95% CI 0.77-0.98) in heart failure with reduced ejection fraction. Only ANG2 and GDF15 remained significantly associated with LVEF recovery after adjustment for age, sex, and Antwerp score and significantly improved the accuracy of the Antwerp score predictions (P < .001). The area under the curve of the Antwerp score in the outcome prediction improved from 0.75 (95% CI 0.67-0.83) to 0.78 (95% CI 0.70-0.86). CONCLUSION: A biomarker panel (ANG2 and GDF15) significantly improved the accuracy of the Antwerp score.

Severe Periprocedural Complications After Ablation for Atrial Fibrillation: An International Collaborative Individual Patient Data Registry.

BACKGROUND: Catheter ablation for atrial fibrillation (AF) including pulmonary vein isolation and possibly further substrate ablation is the most common electrophysiological procedure. Severe complications are uncommon, but their detailed assessment in a large worldwide cohort is lacking. OBJECTIVES: The aim of this study was to determine the incidence of periprocedural severe complications and to provide a detailed characterization of the diagnostic evaluation and management of these complications in patients undergoing AF ablation. METHODS: Individual patient data were collected from 23 centers worldwide. Limited data were collected for all patients who underwent catheter ablation, and an expanded series of data points were collected for patients who experienced severe complications during periprocedural follow-up. Incidence, predictors, patient characteristics, management details, and overall outcomes of patients who experienced ablation-related complications were investigated. RESULTS: Data were collected from 23 participating centers at which 33,879 procedures were performed (median age 63 years, 30% women, 71% radiofrequency ablations). The incidence of severe complications (n = 271) was low (tamponade 6.8‰, stroke 0.97‰, cardiac arrest 0.41‰, esophageal fistula 0.21‰, and death 0.21‰). Age, female sex, a dilated left atrium, procedure duration, and the use of radiofrequency energy were independently associated with the composite endpoint of all severe complications. Among patients experiencing tamponade, 13% required cardiac surgery. Ninety-three percent of patients with complications were discharged directly home after a median length of stay of 5 days (Q1-Q3: 3-7 days). CONCLUSIONS: This large worldwide collaborative study highlighted that tamponade, stroke, cardiac arrest, esophageal fistula, and death are rare after AF ablation. Older age, female sex, procedure duration, a dilated left atrium, and the use of radiofrequency energy were associated with severe complications in this multinational cohort. One in 8 patients with tamponade required cardiac surgery.

Cardioneuroablation for the management of patients with recurrent vasovagal syncope and symptomatic bradyarrhythmias: the CNA-FWRD Registry.

BACKGROUND: Cardioneuroablation has been emerging as a potential treatment alternative in appropriately selected patients with cardioinhibitory vasovagal syncope (VVS) and functional AV block (AVB). However the majority of available evidence has been derived from retrospective cohort studies performed by experienced operators. METHODS: The Cardioneuroablation for the Management of Patients with Recurrent Vasovagal Syncope and Symptomatic Bradyarrhythmias (CNA-FWRD) Registry is a multicenter prospective registry with cross-over design evaluating acute and long-term outcomes of VVS and AVB patients treated by conservative therapy and CNA. RESULTS: The study is a prospective observational registry with cross-over design for analysis of outcomes between a control group (i.e., behavioral and medical therapy only) and intervention group (Cardioneuroablation). Primary and secondary outcomes will only be assessed after enrollment in the registry. The follow-up period will be 3 years after enrollment. CONCLUSIONS: There remains a lack of prospective multicentered data for long-term outcomes comparing conservative therapy to radiofrequency CNA procedures particularly for key outcomes including recurrence of syncope, AV block, durable impact of disruption of the autonomic nervous system, and long-term complications after CNA. The CNA-FWRD registry has the potential to help fill this information gap.

Association between number of vasopressors and mortality in COVID-19 patients.

Study objective: Study the clinical outcomes associated with the number of concomitant vasopressors used in critically ill COVID-19 patients. Design: A single-center retrospective cohort study was conducted on patients admitted with COVID-19 to the intensive care unit (ICU) between March and October 2020. Setting: Rush University Medical Center, United States. Participants: Adult patients at least 18 years old with COVID-19 with continuous infusion of any vasopressors were included. Main outcome measures: 60-day mortality in COVID-19 patients by the number of concurrent vasopressors received. Results: A total of 637 patients met our inclusion criteria, of whom 338 (53.1 %) required the support of at least one vasopressor. When compared to patients with no vasopressor requirement, those who required 1 vasopressor (V1) (adjusted odds ratio [aOR] 3.27, 95 % confidence interval (CI) 1.86-5.79, p < 0.01) (n = 137), 2 vasopressors (V2) (aOR 4.71, 95 % CI 2.54-8.77, p < 0.01) (n = 86), 3 vasopressors (V3) (aOR 26.2, 95 % CI 13.35-53.74 p < 0.01) (n = 74), and 4 or 5 vasopressors(V4-5) (aOR 106.38, 95 % CI 39.17-349.93, p < 0.01) (n = 41) were at increased risk of 60-day mortality. In-hospital mortality for patients who received no vasopressors was 6.7 %, 22.6 % for V1, 27.9 % for V2, 62.2 % for V3, and 78 % for V4-V5. Conclusion: Critically ill patients with COVID-19 requiring vasopressors were associated with significantly higher 60-day mortality.