Long-term clinical outcomes after upgrade to resynchronization therapy: A propensity score-matched analysis

Upgrade to cardiac resynchronization therapy (CRT) is common in Europe, despite little and conflicting evidence.

To compare long-term clinical outcomes in a cohort of patients receiving de novo or upgrade to CRT.

Single-center retrospective study of 295 consecutive patients submitted to CRT implantation between 2007 and 2018. Upgraded and de novo patients complying with a dedicated follow-up protocol were compared in terms of clinical (NYHA class improvement without major adverse cardiac events [MACE] in the first year of follow-up) and echocardiographic (left ventricle end-systolic volume reduction of >15% during the first year) response.

No differences in the rate of clinical (59.3% vs 62.6%, P = .765) or echocardiographic response (72.2% vs 71.9%, P = .970) between groups were observed. Device-related complications were also comparable between groups (8.9% vs 8.4%, P = .892). Occurrence of MACE and all-cause mortality were analyzed over a median follow-up of 3 (interquartile range 1-6) years: MACE occurred less frequently in the de novo group (hazard ratio [HR]: 0.55, 95% confidence interval [CI]: 0.34-0.90, P = .018), but all-cause mortality was similar among groups (HR: 0.87, 95% CI: 0.46-1.64, P = .684). Propensity score-matching analysis was performed to adjust for possible confounder variables. In the propensity-matched samples, all-cause mortality (HR: 1.26, 95% CI: 0.56-2.77, P = .557) and MACE (HR: 0.84, 95% CI: 0.46-1.54, P = .574) were comparable between upgrade and de novo patients.

Survival after upgrade to resynchronization therapy was comparable to de novo implants. Additionally, clinical and echocardiographic response to CRT in upgraded patients were similar to de novo patients.