Pacing-Induced Cardiomyopathy in Right Ventricular Pacemaker Patients: Prevalence and Risk Factors in an Iranian Cohort

Abstract

Background: Right ventricular pacemakers (RVPs) are widely used to manage advanced atrioventricular blocks, significantly improving patient survival and quality of life. However, pacing-induced cardiomyopathy (PiCM) remains a prevalent and under-recognized complication. Objectives: The present study aims to assess the prevalence of PiCM in an Iranian population with RVPs and to identify associated risk factors. Methods: This prospective observational study included 105 patients who received right ventricular apical pacemakers from March 2021 to March 2023. Transthoracic echocardiography was performed before pacemaker implantation and six months post-implantation. The PiCM was defined as either a left ventricular ejection fraction (LVEF) ≤ 40% if baseline LVEF was ≥ 50%, or a reduction of ≥ 10% in LVEF. Results: At six months, 17.1% (n = 18) of patients developed PiCM. A higher prevalence of diabetes mellitus (DM), ischemic heart disease (IHD), and chronic kidney disease (CKD) was observed among the PiCM group. Diabetes mellitus (OR = 3.53; 95% CI 1.78 - 6.45; P = 0.012), IHD (OR = 8.07; 95% CI 5.20 - 29.64; P < 0.001), CKD (OR = 5.29; 95% CI 1.47 - 11.29; P = 0.028), baseline LVEF 65% can accurately predict PiCM (AUC = 0.651; P = 0.033). Conclusions: The prevalence of PiCM among Iranian patients with RVPs aligns with global reports. These findings underscore the importance of routine echocardiographic surveillance and risk stratification in patients with RVPs. Early recognition of high-risk individuals, particularly those with comorbidities or elevated pacing burden, may inform pacing strategies and guide follow-up to reduce the incidence of PiCM.