Abstract P326: Myocardial Ischemia and Mobilization of Circulating Progenitor Cells

Background: Circulating progenitor cells (CPCs) are involved in vascular repair and regeneration. Low levels of CPCs in patients with CAD have been linked to adverse cardiovascular outcomes. The response of CPCs to transient myocardial ischemia in patients with CAD has not been studied before. We aimed to investigate the CPC response to exercise provoked myocardial ischemia (demand ischemia), and compare it to myocardial ischemia detected during pharmacological stress test (flow mismatch). Methods: 570 patients with stable CAD underwent 99mTc sestamibi myocardial perfusion imaging during exercise (69%), or pharmacological stress (31%). myocardial ischemia was defined as a new or worsening impairment in myocardial perfusion using a 17-segment model. CD34+ CPCs were enumerated by flow cytometry at rest and 30 min after stress testing. The change in CPC count was compared between patients with and without myocardial ischemia using mixed linear models. Results: Mean age was 63±9 years, 76% males, 36% with pre...