B-PO02-053 REDUCTION OF LEFT VENTRICULAR GLOBAL LONGITUDINAL STRAIN IN PATIENTS UNDERGOING PACEMAKER IMPLANTATION AND ITS IMPACT ON LONG TERM OUTCOMES

Abstract

Chronic RV pacing >20% is associated with pacing induced cardiomyopathy. However the long term effect of RV pacing on LV global longitudinal strain (GLS) and the impact of GLS decline on clinical outcomes remains unclear. The aim of the study is to determine the impact of RV pacing on LV GLS and the association between decline of GLS and the composite endpoint of heart failure hospitalization (HFH), biventricular (BiV) upgrade or death. This is a single-center retrospective analysis of pts undergoing dual chamber pacemaker implantation between 1/1/2013 to 12/31/2018. Those with pre- and post-implantation echocardiograms suitable for strain analysis via 2D speckle tracking and with long term pacing data were included. A total of 107 patients (mean age 76 ± 11.7 yrs; 57 [53%] female) were followed for a mean duration of 23 ± 17 months. Mean baseline left ventricular ejection fraction (LVEF) was 58.5 ± 10.6% and mean GLS was -17.2 ± 3.9% prior to pacemaker implantation. Twenty-four (22%) patients had a decrease in LVEF of >10% and 43 (40%) patients had a reduction of GLS >15%. Of patients who had a reduction of GLS >15%, 67% had RV pacing burden ≥20% compared to 48% of those without a 15% reduction in GLS (p=.05). Patients with a reduction in GLS >15% had significantly higher rate of cumulative outcomes of HFH, need for BiV upgrade and death (log rank p=.001) (Figure). Significant reductions in left ventricular GLS are more commonly seen than reductions in EF after pacemaker implantation. RV pacing >20% is associated with increased risk for GLS reduction. Left ventricular GLS reduction is associated with increased risk for adverse outcomes.