Endothelial function predicts 5-year adverse outcome in patients hospitalized in an emergency department chest pain unit

BackgroundAlthough endothelial function is a marker for cardiovascular risk, endothelial dysfunction assessment is not routinely used in daily clinical practice. A growing challenge has emerged in identifying patients prone to cardiovascular events. We aim to investigate whether abnormal endothelial function may be associated with adverse 5-year outcomes in patients presenting to a chest pain unit (CPU).MethodsFollowing endothelial function testing using EndoPAT 2000 in 300 consecutive patients without a history of coronary artery disease, patients underwent coronary computerized tomographic angiography (CCTA) or single-photon emission computed tomography according to availability.ResultsMean 10-year Framingham risk score (FRS) was 6.6 ± 5.9%; mean 10-year atherosclerotic cardiovascular disease (ASCVD) risk was 7.1 ± 7.2%; median reactive hyperemia index (RHI) as a measure of an endothelial function 2.0 and mean was 2.0 ± 0.4. During a 5-year follow-up, the 30 patients who developed major adverse cardiovascular events (MACE), including all-cause mortality, nonfatal myocardial infarction, hospitalization for heart failure or angina pectoris, stroke, coronary artery bypass grafting, and percutaneous coronary interventions, had higher 10-year FRS (9.6 ± 7.8 vs. 6.3 ± 5.6%; P = 0.032), higher 10-year ASCVD risk (10.4 ± 9.2 vs. 6.7 ± 6.9%; P = 0.042), lower baseline RHI (1.6 ± 0.5 vs. 2.1 ± 0.4; P < 0.001) and a greater degree of coronary atherosclerotic lesions (53 vs. 3%, P < 0.001) on CCTA compared with patients without MACE. Multivariate analysis demonstrated that RHI below the median was an independent predictor of 5-year MACE (odds ratio 5.567, 95% confidence interval 1.955-15.853; P = 0.001).ConclusionOur findings suggest that noninvasive endothelial function testing may contribute to clinical efficacy in triaging patients in the CPU and in predicting 5-year MACE.Clinical Trials.gov IdentifierNCT01618123.