Cellular cardiomyoplasty refers to the implantation of autologous skeletal muscle cells into the myocardium to reinforce its structure and function. In this study a reproducible method for the creation of a myocardial lesion was developed. The functional benefit of cell implantation was evaluated by 2-dimensional echocardiography for global contraction and color kinesis echocardiography, which allows the precise assessment of the regional contraction.A left ventricular intramyocardial injection with snake cardiotoxin was carried out on a sheep model to induce a well-delineated transmural lesion. Three weeks later, the lesion was assessed by echocardiography. Thereafter, autologous skeletal muscle cells or culture media (control) were injected into the lesion. Two months after cell implantation, the myocardial contraction was again evaluated by echocardiography and the implanted cells were analyzed by a fast myosin heavy chain antibody.1. The snake cardiotoxin produced a well-delineated transmural lesion in all animals. 2. Echocardiographic studies showed a significant improvement in global and regional left ventricular function in cell-treated sheep. 3. Histologic analyses demonstrated satellite cell survival at the periphery of the lesions.Satellite cells implanted in a cardiotoxin-induced myocardial lesion survived for a 2-month period and were associated with a significant functional improvement of both local and global contraction.