Intramyocardial bone marrow mononuclear cell transplantation in ischemic heart failure: Long-term follow-up

Abstract

Long-term results regarding treatment of chronic ischemic heart failure with bone marrow mononuclear cells (BMMCs) have been few. We received encouraging results at the 1-year follow-up of patients treated with combined coronary artery bypass grafting (CABG) and BMMCs, so we decided to extend the follow-up. The study patients had received injections of BMMCs or vehicle into the myocardial infarction border area during CABG in a randomized and double-blind manner. We could contact 36 of the 39 patients recruited for the original study. Pre-operatively and after an extended follow-up period, we performed magnetic resonance imaging, measured pro-B-type amino-terminal natriuretic peptide, reviewed patient records from the follow-up period, and determined current quality of life with the Medical Outcomes Study Short-Form 36 (SF-36) Health Survey. The median follow-up time was 60.7 months (interquartile range [IQR], 45.1-72.6 months). No statistically significant difference was detected in change of pro-B-type amino-terminal natriuretic peptide values or in quality of life between groups. The median change in left ventricular ejection fraction was 4.9% (IQR, -2.1% to 12.3%) for controls and 3.9% (IQR, -5.2% to 10.2%) for the BMMC group (p = 0.647). Wall thickening in injected segments increased by a median of 17% (IQR, -5% to 30%) for controls and 15% (IQR, -12% to 19%) for BMMC patients (p = 0.434). Scar size in injected segments increased by a median of 2% (IQR, -7% to 19%) for controls but diminished for BMMC patients, with a median change of -17% (IQR, -30% to -6%; p = 0.011). In the treatment of chronic ischemic heart failure, combining intramyocardial BMMC therapy with CABG fails to affect cardiac function but can sustainably reduce scar size, even in the long-term.