Intramyocardial bone marrow stem cell transplantation during coronary artery bypass surgery: a meta-analysis.

OBJECTIVE Experimental and clinical studies have suggested that intramyocardial bone marrow stem cell transplantation combined with coronary artery bypass grafting might improve left ventricular function in the setting of chronic ischemic heart disease. We therefore conducted a systematic review and meta-analysis of available publications regarding the efficacy and safety of intramyocardial bone marrow stem cell transplantation during coronary artery bypass grafting. METHODS The databases PUBMED, MEDLINE, Cochrane Controlled Trials Register, and ClinicalTrials.gov (all from their inception to May 2009) were searched for randomized controlled trials and cohort studies of intramyocardial bone marrow stem cell transplantation during coronary artery bypass grafting to treat ischemic heart disease. Six studies were included. RESULTS Compared with control groups, the bone marrow stem cell transplantation group showed a significant improvement of left ventricular ejection fraction from baseline to follow-up (5.40%; 95% confidence interval, 1.36-9.44; P = .009). Moreover, the overall change of left ventricular end-diastolic volume from baseline to follow-up favored the bone marrow stem cell therapy group (9.55 mL; 95% confidence interval, -2.82 to 21.92; P = .13). Major adverse cardiovascular events, including ventricular arrhythmia and the composite of other cardiovascular events, were not significantly different between the bone marrow stem cell therapy group and controls (relative risk for ventricular arrhythmia = 0.951; 95% confidence interval, 0.389-2.325; P = .913; relative risk for cardiovascular event = 1.134; 95% confidence interval, 0.28-4.6; P = .86). CONCLUSIONS Clinical evidence suggests that intramyocardial bone marrow stem cell transplantation in combination with coronary artery bypass grafting is associated with improvements of functional parameters in patients with chronic ischemic heart disease. Furthermore, surgical intramyocardial bone marrow stem cell transplantation seems to be safe.