Peripheral Arterial Tonometry for Risk Stratification in Men With Coronary Artery Disease

Abstract

Coronary artery disease (CAD) risk is not fully revealed by traditional risk factors. Identification of a simple, noninvasive tool that allows for detection of high-risk CAD patients and can be applied in large populations and clinical settings would prove valuable. We sought to test the hypothesis that peripheral arterial tonometry (PAT) would be associated with residual risk in men with CAD. In this study, finger PAT was used to measure pulse wave amplitude (PWA) during reactive hyperemia (RH) and taken as a measure of microvascular endothelial function in 42 men with stable CAD and well controlled low-density lipoprotein cholesterol (LDL-C) levels. Plasma levels of high-sensitivity C-reactive protein (hs-CRP) and lipoprotein-associated phospholipase A2 (Lp-PLA(2)) were measured and used to reclassify men into high-risk (elevated hs-CRP and Lp-PLA(2)), moderate-risk (either elevated hs-CRP or Lp-PLA(2)), or low-risk (low hs-CRP and Lp-PLA(2)) groups. PWA-RH was significantly lower in the high-risk group (1.3 +/- 0.04) compared to the moderate-risk (1.6 +/- 0.07, P < 0.05) and low-risk (2.0 +/- 0.1, P < 0.05) groups. According to binary logistic regression, PWA-RH was a significant predictor of high-risk status among men with CAD (P < 0.05). Measurement of peripheral microvascular endothelial function with PAT may be able to distinguish high-risk men from moderate- and low-risk men with stable CAD and well-controlled LDL-C levels and thus aid in residual risk stratification in this at risk cohort.