Circulating Endothelial Progenitor Cells

To the Editor: Recent studies have shown that endothelial progenitor cells are mobilized within a few hours after acute myocardial infarction, and the level of these cells in peripheral blood remains elevated for up to several days or weeks in patients with acute myocardial infarction, as compared with patients with stable angina and healthy control subjects. 1 , 2 Among 507 participants in the study by Werner et al. (Sept. 8 issue) 3 who had coronary artery disease on angiography, a history of acute, subacute, or myocardial infarction was present in 3.4 percent, 8.5 percent, and 32.1 percent, respectively. The level of endothelial . . .