David T Zhang, Mriganka Nerkar, Saborny Mahmud, Abhijeet Singh, Ibrahim O Almasry, Roger Fan, Eric J Rashba
Preemptive MCS was not associated with a significant difference in all-cause mortality or VT recurrence in patients undergoing VT ablation but was associated with longer procedures, and more procedural complications. The certainty of evidence was very low, reflecting the observational study design, baseline imbalance between groups, and heterogeneity; these findings do not preclude the selective use of MCS in high-risk patients and require confirmation in randomized trials.
BACKGROUND: The benefit of preemptive mechanical circulatory support (MCS) for ventricular tachycardia (VT) ablation remains unclear. This meta-analysis compared the efficacy and safety of preemptive MCS to standard care for VT ablation.
METHODS: An unrestricted literature search of PubMed, Embase, and Web of Science identified studies on preemptive MCS for VT ablation. MCS included percutaneous left ventricular assist devices or extracorporeal membrane oxygenation. The primary endpoint was all-cause mortality; secondary endpoints included VT recurrence, procedural time, procedural complications (vascular access, bleeding, stroke, pericardial effusion, heart failure, myocardial infarction), and 30-day major adverse cardiovascular events (MACE).
RESULTS: Eight studies with 2,262 patients (414 with MCS, 1,848 without) were included. Mean follow-up was 15.8 months, mean age was 62.6 years, 12.5% were women, and mean PAINESD scores were 15.7 in the MCS group and 10.5 in the no-MCS group. There was no significant difference in all-cause mortality (OR 1.58, 95% CI 0.60-4.19, p = 0.36, I²=81%) or VT recurrence (OR 1.03, 95% CI 0.68-1.56, p = 0.90, I²=46%). Preemptive MCS was associated with longer procedural times (mean difference 46.0 min, 95% CI 11.1-80.8, p = 0.01, I²=86%), more procedural complications-driven by vascular access and pericardial effusion (OR 2.25, 95% CI 1.26-4.03, p = 0.006, I²=33%). Thirty-day MACE was not uniformly defined across studies and was therefore not pooled.
CONCLUSIONS: Preemptive MCS was not associated with a significant difference in all-cause mortality or VT recurrence in patients undergoing VT ablation but was associated with longer procedures, and more procedural complications. The certainty of evidence was very low, reflecting the observational study design, baseline imbalance between groups, and heterogeneity; these findings do not preclude the selective use of MCS in high-risk patients and require confirmation in randomized trials.