Serial assessment of endothelial function 1, 6, and 12 months after ST-elevation myocardial infarction

Knowledge about the changes in endothelial function after ST-elevation myocardial infarction (STEMI) is of substantial interest, but serial data are scarce. The aim of the present study was to noninvasively evaluate whether endothelial function, as assessed shortly after primary percutaneous coronary intervention (PPCI) for STEMI, may improve until 12-month follow-up. This prospective observational cohort study was performed in patients in the RESPONSE randomized trial who participated in a substudy and underwent noninvasive assessment of endothelial function at 1 (baseline), 6, and 12-month follow-up after treatment of a STEMI by PPCI. The reactive hyperemia peripheral artery tonometry (RH-PAT) method was used to assess endothelial function (higher RH-PAT index signifies better function). Of the 70 study participants, who were 57.4 ± 9.7 years of age, 55 (78.6%) were male and 9 (13%) had diabetes. The endothelial function deteriorated significantly during follow-up: the RH-PAT index at baseline, 6, and 12-month follow-up was 1.90 ± 0.58, 1.81 ± 0.57, and 1.69 ± 0.49, respectively (p = 0.04). Although patients were carefully treated in outpatient clinics and adequate pharmacological therapy was prescribed, we noted an increase in total cholesterol (p = 0.001), LDL cholesterol (p = 0.002), HbA1C (p = 0.054), and diastolic blood pressure (p = 0.047) However, multivariate analysis revealed that this increase in cardiovascular risk factors could not explain the observed deterioration in endothelial function. In patients with STEMI, we observed a significant deterioration in endothelial function during 12 months after PPCI that could not be explained by changes in the traditional cardiovascular risk profile.