CRT-D was associated with a 35% reduction in all-cause mortality compared with CRT-P (HR 0.65; 95% CI 0.53-0.80), with the survival benefit significantly modified by LBBB, LVEF, and renal function.
Cohort (n=2,271)
Yes
Does CRT-D reduce all-cause mortality compared to CRT-P in patients undergoing cardiac resynchronization therapy, and how do clinical characteristics modify this benefit?
The survival benefit of CRT-D over CRT-P is highly dependent on patient characteristics, with pronounced benefits seen in patients with LBBB, LVEF between 17.9% and 37.6%, and eGFR >31.8 mL/min.
Effect estimate: HR 0.65 (95% CI 0.53-0.80)
Background: Cardiac resynchronization therapy (CRT) is a key intervention for patients with heart failure. The choice between a CRT with defibrillator therapy (CRT-D) and a CRT with pacemaker (CRT-P) is influenced by individual clinical characteristics. This study explores the interaction between these clinical variables and the benefit of CRT-D versus CRT-P on all-cause mortality. Methods: All patients who underwent CRT implantation in three European centres were included in a multicentre, retrospective registry. The impact of clinical variables on all-cause mortality was analysed using interaction tests within multivariable Cox proportional hazard models. Significant interactions were explored to assess how patient characteristics modify the effect of CRT-D compared with CRT-P. Results: A total of 2271 patients with CRT implantation were included. CRT-D was associated with a 35% reduction in all-cause mortality compared with CRT-P hazard ratio (HR) 0.65; 95% confidence interval (CI) 0.53-0.80. Significant interactions were observed for left bundle branch block (LBBB) morphology (P = 0.028), left ventricular ejection fraction (LVEF, P = 0.025) and renal function (P = 0.019). The survival benefit of CRT-D was pronounced in patients with LBBB (HR 0.57; 95% CI 0.44-0.73) but was not significant in those without LBBB (HR 0.81; 95% CI 0.59-1.10). For LVEF at implant, CRT-D provided benefit between 17.9% and 37.6%. Similarly, CRT-D improved outcomes in patients with an estimated glomerular filtration rate >31.8 mL/min but not in those with more advanced renal impairment. No interaction was observed with age at implant (P = 0.286). Conclusions: This study provides insights into the benefits of CRT-D over CRT-P, identifying LBBB morphology, LVEF and renal function as key covariates associated with implantable cardioverter-defibrillator (ICD) therapy's benefit.
Vandenberk et al. (Wed,) conducted a cohort in Heart failure (n=2,271). Cardiac resynchronization therapy with defibrillator (CRT-D) vs. Cardiac resynchronization therapy with pacemaker (CRT-P) was evaluated on All-cause mortality (HR 0.65, 95% CI 0.53-0.80). CRT-D was associated with a 35% reduction in all-cause mortality compared with CRT-P (HR 0.65; 95% CI 0.53-0.80), with the survival benefit significantly modified by LBBB, LVEF, and renal function.