How to choose between a pacemaker or defibrillator for resynchronization therapy?

Abstract

Objective The choice between a resynchronization pacemaker (CRT-P) or defibrillator (CRT-D) is still a matter of debate. We hypothesised that when selecting patients based on co-morbidities and age as proposed by the ESC-guidelines, there would be no long-term survival benefit of CRT-D compared to CRT-P.

Methods We performed a retrospective analysis of patients who received a CRT device at the University Hospitals Leuven between 2001 and 2007. For the analysis of the association between predictors and outcome, uni- and multivariate Cox regression analyses were performed. We present data from three multivariate models.

Results A total of 144 CRT devices were implanted (CRT-D n = 98, CRT-P n = 46). Patients who received a CRT-P were older and had a higher prevalence of co-morbidities. Patients who received a CRT-D had a significant lower mortality. When applying incremental multivariate analysis using 1^st variables with a P < 0.05 in univariate analysis, 2^nd variables with a P < 0.10 and 3^rd adding on top all the baseline variables that were significantly different between the two groups, the significance of a possible survival benefit for CRT-D over CRT-P disappeared: risk model 1, hazard ratio 2.21 (P = 0.008), risk model 2, HR 1.81 (P = 0.069), and risk model 3, HR 1.85 (P = 0.091). The use of amiodarone and the presence of COPD or renal insufficiency remained associated with a significant, higher mortality risk, while the use of beta blockers was protective in all three models.

Conclusion The choice of a CRT-D seemed a predictor of improved survival in simple but not in more complex multivariable analyses. The fact that the survival benefit strongly depended on the number of co-variables suggests that it is at most marginal.

• Heart failure
• CRT
• defibrillator
• demographics
• outcome
• risk score