Introduction and objectives: This study reports the findings in a group of 13 patients aged 53+/-8 years with anterior wall acute myocardial infarction who were revascularized with stents and treated with recombinant human granulocyte colony stimulating factor (G-CSF).
Patients and method: Patients were initially treated with intravenous thrombolytics. The first cardiac catheterization was performed between days 0 and 5 after acute myocardial infarction, when the left anterior descending artery was stented. A 10-day course of 10 .g/kg/day G-CSF was started 5 days after acute myocardial infarction. Blood cell counts and immunophenotyping were done to assess the total number of circulating CD34+ cells and their subpopulations in serial fashion. At 3-month follow-up, cardiac catheterization was repeated. Functional recovery was defined as an increase in ejection fraction.
Results: All patients did well initially, but 1 had spontaneous spleen rupture on day 8 of G-CSF administration, which required emergency splenectomy. The gain in ejection fraction varied among patients from -22 to +18 (mean, 6.2%+/-12%), and correlated directly with the total number of circulating CD34+ CD38- cells/microL on the fifth day of G-CSF treatment (r=0.78; P<.003). The gain in ejection fraction correlated inversely with peak MB fraction creatine kinase (r=-0.82; P<.002).
Conclusion: Stem-cell mobilization with G-CSF is a feasible and safe treatment for patients with revascularized acute myocardial infarction. However, because of the possibility of acute splenitis induced by massive cell mobilization, future studies should be designed with due caution to take this eventuality into account.