7 * Reduced global longitudinal strain one month after RV pacing predicts progression to pacing induced heart failure

Abstract

Introduction: Right ventricular (RV) pacing causes heart failure in up to 9% of patients. A priori identification of patients who will develop pacing induce heart failure (PIHF) represents an important challenge. We aimed to establish whether speckle tracking strain echocardiography (STE), performed soon after pacemaker implantation, can predict development of PIHF. Methods: Fifty-five patients with high-grade atrioventricular block underwent dual chamber pacemaker implantation. At baseline all patients had preserved LV ejection fraction (LVEF > 55%). Two-dimensional echocardiography and 12-lead electrocardiograms were performed before pacemaker implantation and repeated alongside pacemaker interrogation at one and six months. As a function of time, patients were grouped according to the cumulative percentage of ventricular pacing (Cum%VP), determined from pacemaker diagnostics at six months. Baseline, one and six month LVEF and STE findings for group 1 (Cum% VP > 40) were compared to cases where Cum%VP was <40% (Group 2, n=25). Results: At one month there were no cases of PIHF (LVEF <45%). At 6 months, PIHF was observed in 4/30 (13%) group 1 patients. Global longitudinal strain (GLS) values for these cases were compared to strain values for group 1 patients without PIHF and to group 2. Baseline GLS value were comparable between the three groups (−16.0 vs. −16.5 and −17.0; p=0.642). One month GLS was significantly lower in patients with PIHF (−11.3 vs. −14.4 and −16.1; p=0.035). Conclusion: Significant reductions in GLS precede development of PIHF and may be used to identify patients at greatest risk of PIHF before a decline in LVEF occurs.