Prognostic role of brachial reactivity in patients with ST myocardial infarction after percutaneous coronary intervention

OBJECTIVE: We hypothesized that flow-mediated vasodilation (FMD) in the brachial artery as a noninvasive method is of value in providing further predictive insights in a cohort of patients with ST-segment elevation acute myocardial infarction (STEMI) after percutaneous coronary intervention (PCI). METHODS AND RESULTS: One hundred and one patients (62.43+/-9.06, 67 men) with STEMI, undergoing successful primary and rescue PCI, were included in this study. FMDs of all patients were determined using ultrasound after PCI. Patients were tracked for subsequent cardiovascular events. Twenty-nine patients had an event during 12.1+/-2.6 months of follow-up. Multivariate Cox proportional hazard analysis identified a diagnosis of diabetes [hazard ratio (HR): 2.934, 95% confidence interval (CI): 1.314-6.548, P=0.0086], ejection fraction (HR: 0.900, 95% CI: 0.832-0.973, P=0.0082), and FMD (HR: 0.705, 95% CI: 0.573-0.868, P=0.0010) after adjustment of all entered baseline variables. ROC analysis showed that FMD (ROC area: 0.689, P=0.0012; optimal threshold: 5.5% or less) had predictive value with sensitivity of 64%, specificity of 61%, positive predictive value of 40%, and negative predictive value of 81%. CONCLUSION: In patients with STEMI, early evaluation of endothelial function after PCI could help to shed light on the mechanisms that increase the risk of new events. FMD could be used as a surrogate marker of events.