Autologous skeletal myoblast transplantation for the treatment of postinfarction myocardial injury: Phase I clinical study with 12 months of follow-up

Background Experimental studies have shown that skeletal myoblast transplantation into an area of postinfarction left ventricular injury results in an increase of segmental contractile performance that could be related to transplanted myoblasts. Initial experience with autologous skeletal myoblast transplantation in patients with postinfarction myocardial injury has also been obtained. Methods Patients who survived an acute myocardial infarction and were scheduled to undergo coronary artery-bypass grafting were screened by means of dobutamine stress echocardiography and included into the study when no contractility changes within akinetic/dyskinetic segments were observed. Ten patients who gave informed consent were enrolled, and autologous myoblasts (satellite cells) were isolated from the skeletal muscle biopsy., Myoblast injections into the akinetic/dyskinetic area were performed after constriction of the anastomoses during,the coronary artery bypass grafting procedure. Results Myoblast transplantations were performed after 3 weeks of in vitro culture in all patients. One patient died of a recent infarction at day 7 postoperatively because of a recent infarction in a remote area of the left ventricle. The left ventricular ejection fraction increased from 25% to 40% (mean, 35.2%) before the procedure to 29% to 47% (mean, 42.0%) during the 4-month visit (P < .05), and the effect was maintained throughout 12 months of follow-up. Sustained ventricular tachycardia was observed in 2 patients in the early postoperative period and in the other 2,patients after 2 weeks of follow-up. Prophylactic amiodarone infusion was used in the remaining 8 patients and prevented sustained ventricular tachycardia episodes. Conclusions Autologous skeletal myoblast transplantation for the treatment of postinfarction heart failure is feasible. Our initial observations justify further research to validate this method in a clinical practice.