Long-Term Outcome of Intra-Myocardial Injection of Autologous Bone Marrow Mononuclear Cells Combined with Isolated Coronary Artery Bypass Grafting for Patients with Chronic Ischemic Heart Failure

Abstract

<strong>Objective:</strong> This study aimed to investigate whether intra-myocardial injection of autologous bone marrow mononuclear cells (aBMMNCs) into peri-scarred myocardium during coronary artery bypass grafting (CABG) improved the long-term outcome compared with CABG alone.<br /><strong>Methods:</strong> From April 2011 to December 2012, 33 patients with chronic ischemic heart failure were randomly assigned to undergo CABG (control group) or CABG combined with intra-myocardial injection of aBMMNCs (treatment group). The primary endpoints of the study were the changes of left ventricular ejection fraction (LVEF), left ventricular end-diastolic volume (LVEDV), and left ventricular end-systolic volume (LVESV) from baseline to six-month and two-year follow-up, respectively. The secondary endpoints were the changes of III and IV NYHA classification, 6-minute walk test, B-type natriuretic peptide (BNP) from baseline to follow-up, and major adverse cardiovascular events (MACES) during the follow-up.<br /><strong>Results:</strong> No patient died and no severe surgical complication occurred perioperatively in either group. The mean number of transplanted aBMMNCs was 98.5 ± 48.3×106 per patient. The follow-up was completed at six months and 24 months postoperatively. No major transplant-related adverse events were detected during the study. The patients in the treatment group had more significant improvement in LVEF than in the control group at six-month follow-up (8.17% versus 4.71%, P = .020), but this benefit was not found at 24-month follow-up (7.44% versus 5.69%, P = .419). There was no significant difference in changes of LVEDV, LVESV, III and IV NYHA classification, 6-minute walk distance, BNP, and MACES between the two groups all through the study. <br /><strong>Conclusion:</strong> Intra-myocardial injection of aBMMNC transplantation on arrested heart during CABG is a safe procedure based on a longer period observation. The patients with chronic ischemic heart failure can benefit from aBMMNCs transplantation in the short-term (6 months) demonstrated by improved global LVEF compared with the control group; however, this additional benefit dimed with time as showed by 24-month clinical and echocardiographic follow-up results.