Minimal energy requirement for external cardioversion and catheter ablation for long-standing persistent atrial fibrillation

Optimal patient selection for maze procedure in patients undergoing mitral valve disease

OBJECTIVES

Although risk factors for unsuccessful Maze procedure have been demonstrated, an appropriate patient selection is still controversial. In our institute, Maze procedure is indicated for those whom normal sinus rhythm (NSR) was reestablished by intraoperative direct cardioversion (DC) after ventricular unloading by total cardiopulmonary bypass. The purpose of this study was to evaluate the effectiveness of our indication criteria for Maze procedure in patients with mitral valve disease.

METHODS

Between October 2012 and October 2021, MAZE was indicated in 55 patients in whom normal sinus rhythm (NSR) was reestablished by intraoperative direct current cardioversion (DC). Three endpoints and predictors were examined: disappearance of atrial fibrillation (AF), NSR, and A-wave detection.

RESULTS

Restoration of NSR by intraoperative DC was confirmed in 43 patients, and these patients underwent MAZE. AF disappeared in 39 patients (90.7%), and F-wave ≥ 0.1 mV was a significant predictive factor (odds ratio (OR) 20.99, 95% CI 1.22-1079.06). NSR was reestablished in 36 patients (83.7%), and F-wave ≥ 0.1 mV (odds ratio 15.62, 95% CI 1.62-359.86) + AF history ≤ 3 years (OR 8.30, 95% CI 1.09-177.04) were significant predictors. A-wave detection was confirmed in 26 patients (60.5%), and left atrial diameter ≤ 55 mm was a significant predictor (OR 5.22, 95% CI 1.28-24.79).

CONCLUSIONS

Intraoperative DC after ventricular unloading resulted effective patient selection for concomitant Maze procedure. F-wave and AF history were predictive factor of electrical restoration of AF, and left atrial diameter was predictive factor of restoration of atrial function.

Defibrillation threshold of internal cardioversion prior to ablation predicts atrial fibrillation recurrence

BACKGROUND

Many studies have reported the predictors of atrial fibrillation (AF) recurrence after persistent AF (peAF) ablation. However, the correlation between the atrial defibrillation threshold (DFT) for internal cardioversion (IC) and AF recurrence rate is unknown. Here we investigated the relationship between the DFT prior to catheter ablation for peAF and AF recurrence.

HYPOTHESIS

DFT prior to ablation was the predictive factor for AF recurrence after peAF ablation.

METHODS

From June 2016 to May 2019, we enrolled 82 consecutive patients (mean age, 65.0 ± 12.4 years), including 45 with peAF and 37 with long-standing peAF, at Hamamatsu Medical Center. To assess the DFT, we performed IC with gradually increasing energy prior to radiofrequency application.

RESULTS

Forty-nine and 33 patients showed DFT values less than or equal to 10 J (group A) and greater than 10 J or unsuccessful defibrillation (group B). During the mean follow-up duration of 20.5 ± 13.1 months, patients in group B showed significantly higher AF recurrence rates than those in group A after the ablation procedure (p = .017). Multivariate analysis revealed that DFT was the only predictive factor for AF recurrence (odds ratio, 1.07; 95% CI, 1.00-1.13, p = .047).

CONCLUSIONS

The DFT for IC was among the strongest prognostic factors in the peAF ablation procedure.

Left atrial structure and function predictors of recurrent fibrillation after catheter ablation: a systematic review and meta-analysis

BACKGROUND

Catheter ablation (CA) has become a conventional treatment for atrial fibrillation (AF), but remains with high recurrence rate. The aim of this meta-analysis was to determine left atrial (LA) structure and function indices that predict recurrence of AF.

METHODS

We systematically searched PubMed-Medline, EMBASE, Scopus, Google Scholar and the Cochrane Central Registry, up to September 2017 in order to select clinical trials and observational studies which reported echocardiographic predictors of AF recurrence after CA. Eighty-five articles with a total of 16 126 patients were finally included.

RESULTS

The pooled analysis showed that after a follow-up period of 21 ± 12 months, patients with AF recurrence had larger LA diameter with weighted mean difference (WMD: 2·99 ([95% CI 2·50-3·47], P<0·001), larger LA volume index (LAVI) maximal and LAVI minimal (P<0·0001 for both), larger LA area (P<0·0001), lower LA strain (P<0·0001) and lower LA total emptying fraction (LA EF) (P<0·0001) compared with those without AF recurrence. The most powerful LA predictors (in accuracy order) of AF recurrence were as follows: LA strain <19% (OR: 3·1[95% CI, -1.3-10·4], P<0·0001), followed by LA diameter ≥50 mm (OR: 2·75, [95% CI 1·66-4·56,] P<0·0001), and LAVmax >150 ml (OR: 2·25, [95% CI, 1.1-5·6], P = 0·0002).

CONCLUSIONS

Based on this meta-analysis results, a dilated left atrium with diameter more than 50 mm and volume above 150 ml or myocardial strain below 19% reflect an unstable LA that is unlikely to hold sinus rhythm after catheter ablation for atrial fibrillation.

Catheter Ablation of Long-standing Persistent Atrial Fibrillation: a Reckless Challenge or a Way to Real Cure?

Long-standing persistent atrial fibrillation (L-PeAF) is a category in which rhythm control is attempted while atrial fibrillation (AF) is maintained for more than 1 year. Because AF is a progressive disease and L-PeAF accompanies significant electrical and structural remodeling of atria, it is difficult to restore and maintain sinus rhythm in patients with L-PeAF. Nonetheless, the rhythm outcome is being increasingly improved by the development of sophisticated mapping devices, highly efficient catheters, and evidence-based ablation strategies, and the rational choice of patient selection criteria. This review discusses the evolution of the rhythm control outcome of L-PeAF and its future direction of development.