Prognostic value of non-invasive endothelial function index in emergency department patients with undifferentiated chest pain

Stratifying the cardiovascular risk for patients consulting for chest pain (CP) is sometimes difficult. An easy method to predict the prognosis in these patients could be helpful.The aim of the study was to determine the prognostic performance of endothelial function assessment using endothelial peripheral arterial tonometry (Endo-PAT).

This was a prospective study conducted in emergency departments (ED) from March 2016 to September 2017, including patients presenting to the ED for non-traumatic CP. All patients underwent assessment of peripheral endothelial function, by reactive hyperemia index (RHI), using Endo-PAT device. RHI <1.19 identified endothelial dysfunction. Patients were followed by telephone contact, during one month, for major adverse cardiovascular events (MACE). The prognostic performance of RHI was determined by the area under Receiver Operating Characteristic (ROC) curve.

We studied 503 patients with non-traumatic CP. During 1-month follow up, 4.6 % patients had developed MACE. These patients had lower RHI compared to those without MACE (1.24 [IQR: 1.14-1.38] vs 1.50 [IQR: 1.24-1.85], p = 0.04). Area under the ROC Curve at 30-day follow-up was 0.74 for RHI associated to TIMI risk score. The sensitivity, the specificity, the positive and negative predictive value for prediction of MACE at the best cut-off of RHI were 35 %, 83 %, 9 % and 96 % respectively. The addition of RHI to TIMI score improves the sensitivity and negative predictive value.

Combined to TIMI score, RHI testing is a good prognostic tool in patients with undifferentiated CP.