Substrate ablation by dechanneling technique in elderly patients

Introduction

Ventricular tachycardia (VT) ablation through substrate elimination during sinus rhythm has been shown to be both effective and safe. The dechanneling technique, based on the isolation of slow-conduction channels, reduces the need for repeated VT induction and minimizes ablation volume. However, its application in elderly patients has not been specifically evaluated.

Methods

A total of 108 consecutive patients who underwent 112 substrate ablation procedures were included. All of the ablation procedures were done using scar dechanneling during sinus rhythm, without baseline VT induction. The primary procedural goal was the elimination of conducting-channel electrograms, followed by ablation of any residually inducible VT. A prospective analysis was conducted on the subgroup of patients aged ≥70 years. Clinical variables, procedural data, and long-term safety and arrhythmic outcomes were analysed.

Results

54 patients aged ≥70 years (mean age 75 ± 4 years, 94% male) were included; 87% had ischemic cardiomyopathy, with a mean left ventricle ejection fraction (LVEF) of 34 ± 12%. The main clinical characteristics are summarized in the Table. The most common indication for ablation procedure was electrical storm (43%). Non-inducibility of any VT was achieved in 69% of cases. No procedure-related complications occurred. Thirty-day mortality did not differ significantly from younger patients (3.2% vs 1.7%, p=0.6). After long-term follow-up (7.8±3.1 years), VT recurrence occurred in 27% of patients. Total mortality was 39%, predominantly due to non-cardiovascular causes.

Conclusions

Substrate-based ablation using the dechanneling technique in elderly patients is safe and is associated with low early mortality and favourable long-term arrhythmic outcomes.

Table. Baseline characteristics of older patients (≥ 70 years) undergoing scar dechanneling ablation. Quantitative variables are presented as mean ± standard deviation, whereas qualitative variables are presented as counts and percentages.Table