Endothelin-1 levels predict endothelial progenitor cell mobilization after acute myocardial infarction.

INTRODUCTION Endothelin-1 (ET-1), circulating endothelial cells (CEC) and endothelial progenitor cells (EPC) are well-known modulators of endothelial function with important cardiac effects after an acute myocardial infarction. However, the relationship between them has never been assessed. The objective of the present study was to establish the relationship between ET-1, CEC, and EPC concentrations after ST-elevation myocardial infarction (STEMI). METHODS Endothelin-1, CEC, and EPC levels were measured in 61 patients presenting with a first STEMI. Samples were withdrawn acutely 6-24h and 1week after admission. Assessments included reperfusion outcomes (angiography), left ventricular ejection fraction (echocardiography), and 30-day mortality. RESULTS Mean age was 60.6±12.6years and 45 (74%) were males. Higher ET-1 plasma levels were associated with lower EPC count after 1week (7.45±2.53pg/ml if EPCs in the first quartile vs 5.72±1.49pg/ml if EPCs in the fourth quartile; P=0.04). In contrast with CEC and EPC count, higher ET-1 concentrations on admission were associated with Killip≥2 (9.92±2.01pg/ml vs 7.32±2.13pg/ml; P<0.001), post-reperfusion thrombolysis in myocardial infarction (TIMI) <3 (8.65±2.86pg/ml vs 5.87±1.93pg/ml; P=0.002), myocardial blush grade (MBG) <3 (7.46±2.48pg/ml vs 5.99±2.01pg/ml; P=0.004) and higher 30-day mortality (10.29±2.02pg/ml vs 6.57±2.20pg/ml; P=0.005). CONCLUSIONS In STEMI patients, high ET-1 levels on admission predict a lower EPC mobilization after 1week. Endothelin-1 provides better clinical, angiographic and echocardiographic information for prognosis than do CEC and EPC concentrations.