First-Line Catheter Ablation of Monomorphic Ventricular Tachycardia in Cardiomyopathy Concurrent With Defibrillator Implantation: The PAUSE-SCD Randomized Trial

Abstract

Background: Catheter ablation as first-line therapy for ventricular tachycardia (VT) at the time of implantable cardioverter defibrillator (ICD) implantation has not been adopted into clinical guidelines. Also, there is an unmet clinical need to prospectively examine the role of VT ablation in patients with non-ischemic cardiomyopathy (NICM), an increasingly prevalent population referred for advanced therapies globally. Methods: We conducted an international, multi-center, randomized controlled trial enrolling 180 patients with cardiomyopathy and monomorphic VT with an indication for implantable cardioverter defibrillator (ICD) implantation to assess the role of early, first-line ablation therapy. A total of 121 patients were randomized (1:1) to ablation + an ICD versus conventional medical therapy + an ICD. Patients who refused ICD (n=47) were followed in a prospective registry after stand-alone ablation treatment. The primary outcome was a composite endpoint of VT recurrence, cardiovascular hospitalization, or death. Results: Randomized patients had a mean age of 55 years old (IQR 46-64) and left ventricular ejection fraction of 40 % (IQR 30-49 %); 81 % were male. The underlying heart disease was ischemic cardiomyopathy (ICM) in 35 %, NICM in 30 %, and arrhythmogenic cardiomyopathy (ARVC) in 35 %. Ablation was performed a median of 2 days prior to ICD implantation (IQR 5 days prior to 14 days after). At 31-months, the primary outcome occurred in 49.3 %of the ablation group and 65.5 % in the control group (HR 0.58, 95 % CI, 0.35-0.96; P=0.04). The observed difference was driven by a reduction in VT recurrence in the ablation arm (HR 0.51 [95 %CI, 0.29-0.90 ]; P=0.02). A statistically significant reduction in both ICD shocks (10.0 vs 24.6 %; p=0.03) and anti-tachycardia pacing (16.2 % vs 32.8 %; p=0.04) was observed in patients who underwent ablation compared with control. No differences in cardiovascular hospitalization (32.0 % vs. 33.7 %; HR 0.82 [95 % CI, 0.43-1.56 ]; P=0.55) or mortality (8.9% vs 8.8 %, HR 1.40 [95 %CI, 0.38-5.22 ]; P=0.62]) were observed. Ablation-related complications occurred in 8.3 % of patients. Conclusions: Among patients with cardiomyopathy of varied etiologies, early catheter ablation performed at the time of ICD implantation significantly reduced the composite primary outcome of VT recurrence, cardiovascular hospitalization, or death. These findings were driven by a reduction in ICD therapies.

Long-Term Outcomes after Catheter Ablation of Ventricular Tachycardia in Dilated vs. Ischemic Cardiomyopathy

“…The VT-free survival after one year of 63% in the ICM cohort is in accordance with data of these studies. A newly published study was the first prospective randomized trial to include patients with non-ischemic cardiomyopathy [ 14 ]. The study population consisted of three relatively equally distributed groups with ischemic cardiomyopathy, non-ischemic cardiomyopathy, and arrhythmogenic right ventricular dysplasia and managed to show the feasibility of catheter ablation in reducing the rate of VT recurrence and rehospitalization.…”

Outcomes of early catheter ablation for ventricular tachycardia in adult patients with structural heart disease and implantable cardioverter-defibrillator: An updated systematic review and meta-analysis of randomized trials

“…The use of beta-blockers was around 75% in three studies (26,29,32) and >90% in the other five studies. ACEIs/ARBs were used in at least 87% of the patients in five studies (25,27,28,30,31).…”

Can Early Ablation of Ventricular Tachycardia Improve Survival?

“…The PAUSE-SCD trial 2 aimed to determine whether catheter ablation would reduce the composite end point of VT recurrence, cardiovascular hospitalization, or death in patients receiving an ICD after an episode of spontaneous or inducible VT. They randomized 133 patients to ablation versus standard care.…”

“…In this issue of the journal, 2 important randomized trials address the role of catheter ablation for preventing sustained monomorphic ventricular tachycardia (VT) in patients with structural heart disease. 1,2…”