Dib et al. (2005) Safety and feasibility of autologous myoblast transplantation in patients with ischemic cardiomyopathy: four-year follow-up. Circulation 112: 1748–1755

Autologous myoblasts can be transplanted into infarcted myocardial tissue safely, with possible benefits on cardiac function, a 4-year pilot study has shown. Following on from previous studies which showed that human skeletal myoblasts can be grafted into the postinfarction scar tissue of patients with ischemic heart disease, Dib et al. have assessed the immediate and long-term safety of the procedure.

Thirty patients with acute myocardial infarction and left ventricular dysfunction took part in this study. They received an injection of up to 3 × 108 skeletal myoblast cells while undergoing coronary artery bypass grafting (CABG; n = 24) or implantation of a left ventricular assist device (LVAD) as a bridge to heart transplantation (n = 6). The procedure was well tolerated, with patients experiencing postoperative recovery typical for bypass or LVAD surgeries. Although three patients died in the LVAD group and one in the CABG group, these deaths were related to surgical complications and a link to implantation of skeletal myoblasts was not shown. Nonsustained ventricular tachycardia was the most serious adverse event that might have been linked with the procedure, and this occurred in only 2 of 24 CABG patients.

Subsequent echocardiography revealed a marked increase in left ventricular ejection fraction in treated patients, and positron emission tomography indicated that viability of the infarcted myocardial tissue had also improved. Histologic evaluation in four heart-transplant recipients showed that transplanted myoblasts had survived and formed myofibers, without disturbing or distorting normal myocardial tissue.

Together, these encouraging data warrant further clinical trials to assess potential benefits of transplanting autologous myoblasts in patients with ischemic cardiomyopathy.