A systematic review and meta-analysis of cardiac resynchronization therapy in inotrope-dependent heart failure: an update

Abstract Background Inotrope-dependent heart failure (HF) carries a poor prognosis. Advanced mechanical supports have been viewed as primary treatment modalities for these patients, but cardiac resynchronization therapy (CRT) is an emerging alternative. Whether CRT is viable in HF patients who require inotropic support is uncertain. Purpose To assess outcomes of CRT in end-stage inotrope-dependent HF. Methods Following PRISMA guidelines, we searched Medline, EMBASE, Scopus, and Cochrane Library until December 31st 2022, with the following terms: "end-stage heart failure," "catecholamine-dependent overt heart failure," "inotrope-dependent heart failure," "advanced heart failure," "New York Heart Association class IV," "NYHA class IV." These terms were combined with "cardiac resynchronization therapy" OR "CRT" OR "biventricular device". Studies were included if: 1) HF patients required on inotropic support at CRT implantation; 2) patients were at least 18 years old; and 3) provided a clear definition of "inotrope dependence" or "inability to wean." A meta-analysis with random effects was performed in R (Version 3.5.1) with data presented as mean ± standard error. Results 19 studies comprised of 386 inotrope-dependent HF patients (mean age 64.4 ± 1.2 years, 76.9% male, 54.6% non-ischemic cardiomyopathy, mean QRS duration 168.0 ± 4.6 ms, mean follow-up 778 ± 110.7 days) were included for meta-analysis. A large majority of patients survived until discharge at 90% (95% CI: 81.0%-96.8%, I2=51%, p=0.04, Figure 1A), 88.6% were weaned off inotropes (95% CI: 77.5%-96.8%, I2=64%, p