Safety, long-term outcomes and predictors of recurrence after first-line combined endoepicardial ventricular tachycardia substrate ablation in arrhythmogenic cardiomyopathy. Impact of arrhythmic substrate distribution pattern. A prospective multicentre study

• Published in: Europace (London, England) Vol. 19; no. 4; pp. 607 - 616
• Main Authors: Berruezo, Antonio, Acosta, Juan, Fernández-Armenta, Juan, Pedrote, Alonso, Barrera, Alberto, Arana-Rueda, Eduardo, Bodegas, Andrés Ignacio, Anguera, Ignasi, Tercedor, Luis, Penela, Diego, Andreu, David, Perea, Rosario Jesus, Prat-González, Susana, Mont, Lluis
• Format: Journal Article
• Language: English
• Published: England 01.04.2017
• Subjects: Adult; Arrhythmogenic Right Ventricular Dysplasia - diagnosis; Arrhythmogenic Right Ventricular Dysplasia - mortality; Arrhythmogenic Right Ventricular Dysplasia - surgery; Catheter Ablation - mortality; Catheter Ablation - statistics & numerical data; Causality; Combined Modality Therapy - mortality; Combined Modality Therapy - statistics & numerical data; Comorbidity; Endocardium - surgery; Female; Humans; Longitudinal Studies; Male; Middle Aged; Pericardium - surgery; Prevalence; Recurrence; Risk Factors; Secondary Prevention - statistics & numerical data; Spain - epidemiology; Survival Rate; Tachycardia, Ventricular - diagnosis; Tachycardia, Ventricular - mortality; Tachycardia, Ventricular - prevention & control; Treatment Outcome; Long-term outcomes; Epicardial ablation; Ventricular tachycardia; Scar dechanneling; Arrhythmogenic cardiomyopathy
• ISSN: 1099-5129; 1532-2092
• DOI: 10.1093/europace/euw212

First-line endoepicardial ventricular tachycardia (VT) ablation has been proposed for patients with arrhythmogenic cardiomyopathy (AC). This study reports procedural safety, outcomes, and predictors of recurrence. Forty-one consecutive patients [12 with left ventricle (LV) involvement, 7 left-dominant] underwent first-line endoepicardial VT substrate ablation. Standard bipolar and unipolar thresholds were used to define low-voltage areas (LVA). Arrhythmogenic substrate area (ASA) was defined as the area containing electrograms with delayed components. Implantable cardioverter defibrillator interrogations were evaluated for VT recurrence. Epicardial LVA was larger in all cases (102.5 ± 78.6 vs. 19.3 ± 24.4 cm2; P< 0.001). Consistent with an epicardium-to-endocardium arrhythmogenic substrate progression pattern, epicardial ASA (epi-ASA) was negatively correlated with bipolar endocardial LVA (r = -0.368; P= 0.035) and with endocardial bipolar/unipolar-LVA (Bi/Uni-LVA) ratio (r= -0.38; P= 0.037). A Bi/Uni-LVA ratio >0.23 predicted an epi-ASA ≤10 cm2 (100% sensitivity, 84% specificity). Patients showing an epi-ASA < 10 cm2 required less epicardial (8.4 ± 5.8 vs. 25.3 ± 16; P= 0.045) and more endocardial (16.5 ± 8.6 vs. 7.5 ± 8.2; P= 0.047) radiofrequency applications. One patient with epi-ASA < 10 cm2 died of cardiac tamponade after epicardial puncture. Acute success (no VT inducibility after procedure) was achieved in 36 patients (90%). After 32.2 ± 21.8 months, 11 (26.8%) patients had VT recurrences. Left-dominant AC was associated with an increased risk of recurrence (HR = 3.41 [1.1-11.2], P= 0.044; log-rank P= 0.021). First-line endoepicardial VT substrate ablation achieves good long-term results in AC. Left-dominant AC is associated with an increased risk of recurrence. The Bi/Uni-LVA ratio identifies patients with limited epicardial arrhythmogenic substrate in whom the indication of epicardial approach should be more cautiously assessed.