The therapeutic benefit of upgrade to cardiac resynchronization therapy in patients with pacing-induced cardiomyopathy

BACKGROUND Pacing-induced cardiomyopathy (PICM) is an important cause of heart failure in patients with a right ventricular pacing burden. Recent evidence suggests that an upgrade to cardiac resynchronization therapy (CRT) may confer benefit in PICM.OBJECTIVE To assess the extent and identify predictors of improvement following upgrade to CRT in patients with PICM. METHODS We retrospectively analyzed 43 patients undergoing CRT upgrade for PICM over the 10-year period of 2011 to 2021 at our center. All patients with PICM who underwent device upgrade from a dual-or single-chamber ventricular pacemaker to CRT were included. PICM was defined as a decrease of >10% in left ventricular ejection fraction (LVEF), resulting in an LVEF <50% among patients with >20% Right ventricular pacing burden without an alternative cause for cardiomyopathy.RESULTS LVEF significantly improved from 28.7% preupgrade to 44.3% post-CRT upgrade (P < .01). Of 37 patients with severe LV dysfunction, 34 (91.9%) improved to an LVEF >35% and 13 (35.1%) improved to an LVEF >50%. The LV end-diastolic diameter decreased from 5.9 cm preupgrade to 5.4 cm postupgrade (P < .01). Using linear regression, angiotensin-converting enzyme inhibitor or angiotensin receptor blocker use was associated with significant LVEF improvement (+7.21%, P = .05). We observed a low rate of complications, and 1 in 4 CRT upgrades required venoplasty (n = 10 of 43, 23.3%).CONCLUSION We provide further evidence for the benefit of CRT upgrade in the management of patients with PICM.