Upgrading Right Ventricular Pacing to Cardiac Resynchronization in HFrEF Patients Improves Symptoms and Functional Outcomes

Background: In the BUDAPEST (Biventricular Upgrade on left ventricular reverse remodeling and clinical outcomes in patients with left ventricular Dysfunction and intermittent or permanent APical/SepTal right ventricular pacing)-CRT Upgrade randomized trial, the authors have demonstrated improved mortality and morbidity after cardiac resynchronization therapy (CRT) upgrade in patients with heart failure with reduced ejection fraction (HFrEF) with high right ventricular (RV) pacing burden.

Objectives: This substudy sought to examine the impact of CRT upgrade on symptoms, functional outcome, and exercise capacity.

Methods: In the BUDAPEST-CRT Upgrade trial, 360 HFrEF patients with pacemaker or implantable cardioverter-defibrillator (ICD) and ≥20% RV pacing burden were randomly assigned (3:2) to cardiac resynchronization therapy with defibrillator (CRT-D) upgrade (n = 215) or ICD (n = 145). The prespecified tertiary endpoints were changes in quality of life (QoL) (EQ-5D-3L), NYHA functional class, 6-minute walk test, and N-terminal pro-B-type natriuretic peptide (NT-proBNP) levels.

Results: Up to 12 months, NYHA functional class improved in the CRT-D upgrade arm compared with ICD only (adjusted OR: 0.50 [95% CI: 0.32-0.80]; P = 0.003). A remarkable decrease was observed in NT-proBNP levels in the CRT-D arm (adjusted difference -1,257 pg/mL [95% CI: -2,287 to -228]; P = 0.017). The progression of age-related worsening of QoL was moderated by CRT-D upgrade (EQ-5D-3L difference by each year: 0.015 [95% CI: 0.005-0.025]; P interaction = 0.003). However, exercise tolerance (6-minute walk test) remained unchanged in both groups.

Conclusions: HFrEF patients with pacemaker/ICD and ≥20% RV pacing burden receiving CRT upgrade showed a substantial improvement in NYHA functional class and decrease in natriuretic peptide levels, as compared with ICD alone. Moreover, CRT-D upgrade could moderate the progression of worsening of QoL attributed to ageing in this vulnerable, elderly patient population. (Biventricular Upgrade on left ventricular reverse remodeling and clinical outcomes in patients with left ventricular Dysfunction and intermittent or permanent APical/SepTal right ventricular pacing [BUDAPEST]-CRT Upgrade trial).