RESUMO
BACKGROUND: Myocardial damage after myocardial infarction (MI) was deemed irreversible after late reperfusion. Administration of multipotent stem cell (MSC) into such infarct may regenerate the myocardium and capillary network. HYPOTHESIS: Transcoronary infusion of bone marrow derived multipotent stem cells into infarcted related artery after acute myocardial infarction is feasible, safe and improve left ventricular function. METHODS: We conducted a pilot study in patients who survived ST-elevation MI with late reperfusion therapy and remained hemodynamically stable. Bone marrow derived MSC was infused into a patent infarct-related coronary artery during brief low pressure (2 atm) balloon inflation. A 3-T gadolinium-based MRI was performed at baseline and 8 weeks later to evaluate infarct area and LV function. RESULTS: We enrolled 10 patients, age 63.8 +/- 2.8 years 5.2 +/- 4.12 x 10(6) MSC were infused via coronary artery 24.8 +/- 16 days after infarction. The procedures were successful in all patients without any in-hospital event. Infarct size by MRI decreased by 5.84% (P = .018) over 8 weeks. Mean baseline left ventricular ejection fraction (LVEF) was 44.1% +/- 9% and was 46.3% +/- 9% at 8 weeks (P = .34). A trend of smaller LV end-systolic volume with 65.02 +/- 18.2 ml vs 63.04 +/- 21.89 ml (P = .09) with no change of LV end-diastolic volume observed. CONCLUSION: MSC infusion into coronary circulation was feasible and safe after myocardial infarction. Infarct size was reduced with preservation of LV geometry.
