Peripheral endothelial function and cardiovascular events in high-risk patients

Area of Science:

• Cardiology
• Vascular Biology
• Biomarkers

Background:

• Endothelial dysfunction is a key factor in vascular vulnerability.
• Reactive hyperemia index (RHI) noninvasively assesses endothelial function using peripheral arterial tonometry.
• Existing risk scores like SYNTAXsc and Framingham Risk Score (FRS) predict cardiovascular events.

Purpose of the Study:

• To determine the added prognostic value of endothelial function (RHI) to SYNTAXsc and FRS.
• To evaluate RHI's ability to predict cardiovascular events in high-risk patients.

Main Methods:

• Prospective study of 528 high-risk patients (2006-2011).
• Measured RHI before coronary angiography; assessed coronary complexity using SYNTAXsc.
• Followed patients for cardiovascular events until August 2012, including death, MI, stroke, and revascularization.

Main Results:

• Multivariate analysis identified B-type natriuretic peptide (BNP), SYNTAXsc, and RHI as independent predictors of cardiovascular events.
• RHI was a significant independent predictor (HR per 0.1: 0.761; P<0.0001).
• Adding RHI improved risk reclassification by 27.5% (P<0.0001) and increased the C-statistic (0.728 to 0.766; P=0.031).

Conclusions:

• Advanced endothelial dysfunction is significantly correlated with future cardiovascular events in high-risk individuals.
• RHI measurement enhances cardiovascular risk prediction when combined with FRS, BNP, and SYNTAXsc.
• This physiological vascular measurement offers improved risk discrimination for high-risk patients.