Purpose: To report a case-controlled safety and feasibility study of transcatheter transplantation of autologous skeletal myoblasts as a stand-alone procedure in patients with ischemic heart failure.
Methods: Six men (mean age 66.2+/-7.2 years) were eligible for transcatheter transplantation of autologous skeletal myoblasts cultured from quadriceps muscle biopsies. Six other men (mean age 65.7+/-6.3 years) were selected as matched controls (no muscle biopsies). A specially designed injection catheter was advanced through a femoral sheath into the left ventricle cavity, where myoblasts in solution (0.2 mL/injection) were injected into the myocardium via a 25-G needle. At baseline and in follow-up, both groups underwent Holter monitoring, a 6-minute walk test, New York Heart Association (NYHA) class determination, and echocardiography with dobutamine challenge.
Results: Skeletal myoblast transplantation was technically successful in all 6 patients with no complications; 19+/-10 injections were performed per patient (210 x 10(6)+/-150 x 10(6) cells implanted per patient). Left ventricular ejection fraction (LVEF) rose from 24.3%+/-6.7% at baseline to 32.2%+/-10.2% at 12 months after myoblast implantation (p=0.02 versus baseline and p<0.05 versus controls); in matched controls, LVEF decreased from 24.7%+/-4.6% to 21.0%+/-4.0% (p=NS). Walking distance and NYHA functional class were significantly improved at 1 year (p=0.02 and p=0.001 versus baseline, respectively), whereas matched controls were unchanged.
Conclusions: Transcatheter transplantation of autologous skeletal myoblasts for severe left ventricular dysfunction in postinfarction patients is feasible, safe, and promising. Scrutiny with randomized, double-blinded, multicenter trials appears warranted.