CD34 and myocardial infarction: The percentage of apoptotic microparticles was also assessed because it has been reported that apoptotic circulating progenitor/stem (annexin V+/CD34+) cells are increased after acute myocardial infarcts [25], and apoptotic microparticles may reflect target cell dysfunction (e.g. annexin V+ endothelial microparticles in stroke patients with endothelial dysfunction) [26].