Abstract 11015: Pacemaker Lead Insertion Sites Contribute to Regional and Global Ventricular Dysfunction

Abstract

Introduction: Ventricular pacing can cause dysfunction but how the lead is anchored to the myocardium has not been studied. We evaluated patterns of regional and global ventricular function in patients with a ventricular pacemaker or defibrillator using cine cardiac CT (CCT). Methods: This was a single center retrospective study of patients with a ventricular pacemaker or defibrillator who underwent a cine CCT from September 2020 to June 2021. Regional wall motion abnormalities (RWMAs) were assessed in relation to lead insertion site (sew-on vs screw-in) and pacing activity (active vs. inactive). Results: A total of 122 ventricular lead insertion sites were analyzed in 43 patients (53% male, median age 20 years, range 3-57 years). Thirteen patients (30%) had palliated single ventricle physiology, twenty-nine patients had congenital heart disease with biventricular circulation (67%), and one patient had a structurally normal heart (2%). RWMAs were present in 51/122 (42%) lead insertion sites among 23/43 (53%) patients. The prevalence of a lead insertion site associated RWMA was higher with active pacing (54% vs 19%; p < 0.001) and highest for active epicardial sew-on sites ( Figure 1 ). RWMAs were not associated with position of the insertion site relative to the chest wall (p = 0.85) or the distance between the two heads of a bipolar lead (p = 0.23). Patients with lead insertion site associated RWMAs had a lower systemic ventricular ejection fraction (mean of 37.5% vs 52.5%, p < 0.001) compared to those without a RWMA. Conclusions: Pacemaker lead insertion site RWMAs are common and associated with systemic ventricular dysfunction. The mechanism and clinical significance of this regional and global dysfunction warrant further study.