Abstract
BACKGROUND: Pacing-induced cardiomyopathy (PICM) has been reported among patients with transvenous pacemakers (TVP). Recent reports have suggested that the incidence may be lower among patients with leadless pacemakers (LP). We performed a multicenter retrospective study to better define these rates and to identify any potential risk factors. OBJECTIVE: To determine the rates of PICM between LP and TVP and risk factors for development of PICM in each cohort. METHODS: Patients implanted with either a Micra transcatheter LP or TVP between November 2015 and January 2022 were identified from medical records at 3 large medical centers. PICM was defined as a decrease in left ventricular ejection fraction (LVEF) from pre-implant in patients with a baseline LVEF of ≥50% with a resulting post-implant LVEF ≤40% who received at least 20% ventricular pacing. Logistic regression was used to determine univariate and multivariable predictors of PICM. RESULTS: A total of 176 patients with LP and 522 patients with TVP implantations were included for analysis. Of these, 6.3% of patients with LP and 7.9% of patients with TVP developed PICM (odds ratio [OR]: 0.78, 95% confidence interval [CI]: 0.39-1.56, P = .480). Rates of PICM were not significantly different between the 3 centers. Multivariable analysis revealed prolonged paced QRS as a predictor of PICM (OR 1.02 [1.00-1.03], P = .009) and higher pre-implantation LVEF as protective against its development (OR 0.92 [0.88-0.97], P = .001). CONCLUSION: PICM rates are comparable between LP and TVP implantation. Prolonged paced QRS is a predictor for development of PICM and higher pre-implantation LVEF is protective.