Autologous smooth muscle cell transplantation improved heart function in dilated cardiomyopathy

Background. Transplantation of myocytes into scarred myocardium has been sh own to inhibit ventricular remodeling and maintain myocardial contractility . However, the effect of cell transplantation on hearts with global rather than regional dysfunction is unknown. Therefore, we evaluated the effect of transplantation of autologous smooth muscle cells on the morphometry and f unction of dilated cardiomyopathic hearts. Methods. Smooth muscle cells were isolated from the ductus deferens of 13-w eek-old BIO 53.58 hamsters with dilated cardiomyopathy, and cultured for 4 weeks before transplantation. Smooth muscle cells (4 x 10(6) cells) or cult ure medium were injected into 17-week-old animals in the transplantation an d control groups (n = 12 each), respectively. Prelabeling of the smooth mus cle cells with 5-bromo-2'-deoxyuridine was performed before transplantation in a group of transplanted hamsters. Another group (sham, n = 12) underwen t the operation but did not receive an injection either of smooth muscle ce lls or of culture medium. Four weeks after transplantation, heart function was evaluated in a Langendorff preparation. Results. Musclelike tissue, labeled with 5-bromo-2'-deoxyuridine, was found at the site of transplantation in the cell-transplanted animals. The cell- transplanted hearts were smaller (p < 0.001), and had greater developed pre ssures and maximum rate of increase of left ventricular pressure (both p < 0.001) than control and sham hearts. Control hamsters injected with culture medium did not differ from sham-operated animals. Conclusions. Transplantation of autologous smooth muscle cells prevented ca rdiac dilatation and improved ventricular function in hamsters with dilated cardiomyopathy. (Ann Thorac Surg 2000;70:859-65) (C) 2000 by The Society o f Thoracic Surgeons.