Cardiac Resynchronization Therapy in Inotrope-Dependent Heart Failure Patients: A Systematic Review and Meta-Analysis

Objectives: The purpose of this study was to evaluate outcomes after cardiac resynchronization therapy (CRT) in inotrope-dependent patients with heart failure (HF) to ascertain the viability of CRT in these patients.

Background: During the last decade, significant numbers of trials have demonstrated the beneficial effect of CRT in the treatment of patients with HF and systolic dysfunction, prolonged QRS complex duration, and New York Heart Association functional class III or IV. However, it is currently undetermined whether CRT may benefit patients who require inotropic support.

Methods: The authors systematically searched Medline, Embase, Scopus, and the Cochrane Library through March 2017 for studies evaluating outcomes after CRT in inotrope-dependent patients with HF. The study analyzed 8 studies including 151 patients. Most of the patients were in New York Heart Association functional class IV (80.1%), and all had severe systolic HF, with a left ventricular ejection fraction <30% and a significant intraventricular conduction delay in their surface electrocardiogram (QRS complex duration >130 ms).

Results: The pooled analysis demonstrated that 93% of the reported patients (95% confidence interval: 86% to 100%) were weaned from inotropic support after CRT, and the overall 12-month survival rate was 69% (95% confidence interval: 56% to 83%).

Conclusions: This study suggests that rescue CRT may be considered a viable therapeutic option in inotrope-dependent patients with HF. In these patients, rescue CRT may allow them to be weaned from inotropic therapy, improve their quality of life, and decrease the rate of mortality; furthermore, rescue CRT may serve as a possible bridge to cardiac transplantation or left ventricular assist device therapy.