RESUMO
OBJECTIVES: The aim of this study was to evaluate the effect of myoblast transplantation on left ventricular function, perfusion, and scar formation after compromised coronary flow. DESIGN: A coronary vessel with Ameroid-induced stenosis was ligated and skeletal muscle was biopsied for isolation and cultivation of myoblasts. Two weeks after ligation, animals were randomly selected to receive intramyocardial injections of 2 x 10(6) myoblasts or vehicle. Fifteen animals survived the whole study period (n=9 and n=6, respectively). All animals underwent cardiac magnetic resonance imaging (MRI) and angiography pretreatment and four weeks posttreatment. RESULTS: Peak filling rate of the left ventricle improved in the myoblast group (p=0.0048), but not in the control group. Peak ejection rate and duration of diastole improved only in the myoblast group (p=0.049 and p=0.0039, respectively). Ejection fraction or local thickening did not change. Fibrosis and perfusion were similar in both groups, but more microvessels were present histologically in the myoblast group. CONCLUSIONS: In this preclinical study, autologous myoblast transplantation improved ischemic heart function via enhanced diastolic filling of the left ventricle.