Korean Circ J.  2021 May;51(5):455-468. 10.4070/kcj.2020.0415.

Ventricular Arrhythmia Burden as a Marker of Success Following Catheter Ablation of Ventricular Arrhythmias in Patients with Structural Heart Disease

• Bennett R
• Turnbull S
• Kotake Y
• Campbell T
• Kumar S

• KMID: 2515772
• DOI: http://doi.org/10.4070/kcj.2020.0415

Abstract

Background and Objectives
There is little emphasis on the efficacy of catheter ablation for ventricular arrhythmia (VA) when using VA burden reduction as a marker for success. We examined the efficacy of catheter ablation using VA burden, rather than VA recurrence as a marker of success, following catheter ablation of structural heart disease (SHD) related VA.
Methods
Catheter ablation of SHD related VA was performed at a single centre over 4-years. VA episodes and implantable cardioverter defibrillator (ICD) therapies were recorded over the 6-months before and after final ablation. Outcomes were reported in terms of burden reduction and compared to singular VA recurrence.
Results
Overall, 108 patients were included in the study. Mean age 64.2±13.9 years, 86% male, mean left ventricular ejection fraction (LVEF) 42±16%. Median VA episodes and ICD therapy were significantly reduced after ablation (VA before: 10 [interquartile range, IQR: 2–38] vs. VA after: 0 [IQR: 0–2], p<0.001; anti–tachycardia pacing [ATP] before: 16 (IQR: 1.5– 57) vs. ATP after: 0 [IQR: 0–2], p<0.001; shocks before: 1 [IQR: 0–5] vs. shocks after: 0 [IQR: 0–0], p<0.001). Procedural success at 6-months was significantly higher when considering ≥75% reduction in VA burden, rather than a singular VA-free survival (83% vs. 67%, p=0.001).
Conclusions
The vast majority (>80%) of patients achieve reduction in VA burden (≥75% reduction) after catheter ablation for VA. This data suggests that catheter ablation is highly therapeutic when procedure success is defined as reduction in VA, rather than using a single VA recurrence as a metric for failure.

Keyword

Ventricular tachycardia; Catheter ablation; Cardiomyopathy; Sudden cardiac death; Defibrillator

Figure

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  Figure 1 Burden of VA episodes (A), ATP (B), and ICD shocks (C) per patient during the 6-months before (red), and after (blue) catheter ablation. Each line represents a patient, with the burden of episodes after ablation arranged from highest (at the bottom) to lowest (at the top). The figure demonstrates significant reductions in the number of VA episodes, ATP and shocks in the majority of patients following catheter ablation. The upper values have been capped at 500 in VA and ATP episodes (A, B), and 100 in the number of shocks (C).ATP = anti-tachycardia pacing; ICD = implantable cardioverter defibrillator; VA = ventricular arrhythmia.

• 

  Figure 2 Burden of VA episodes (A), ATP (B), and ICD shocks (C) per patient in ICM and NICM subgroups during the 6-months before (red), and after (blue) catheter ablation in the SHD subgroups ICM and NICM. Each line represents a patient, with the burden of episodes after ablation arranged from highest (at the bottom) to lowest (at the top).The figure demonstrates significant reductions in the number of VA episodes, ATP and shocks in the majority of patients, in both SHD subgroups following catheter ablation. The upper values have been capped at 500 in the VA and ATP episodes (A-D), and 100 in the number of shocks (E, F).ATP = anti-tachycardia pacing; ICD = implantable cardioverter defibrillator; ICM = ischemic cardiomyopathy; NICM = non-ischemic cardiomyopathy; SHD = structural heart disease; VA = ventricular arrhythmia.

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