Augmentation Index Does Not Reflect Risk of Coronary Artery Disease in Elderly Patients

BACKGROUND: Augmentation index (AI) has been used as a clinical index of arterial stiffness and has been reported to be an independent predictor of cardiovascular events, but some investigators have reported that AI is not a useful marker to identify coronary artery disease (CAD) in elderly patients. The majority of CAD patients are elderly people, therefore the aim of this study was to examine whether AI is a useful marker to identify the risk of CAD. METHODS AND RESULTS: A total of 120 patients (69±10 years of age; 83 male) who underwent cardiac catheterization for suspected CAD were enrolled. Invasive central blood pressure (BP) was measured using a fluid-filled catheter. Non-invasive AI was calculated by the SphygmoCor (AtCor Medical) system at the end of catheterization. Subjects consisted of 99 patients with CAD and 21 patients without CAD. There was no significant difference in AI between the CAD and the non-CAD groups (24±10 vs. 24±14%). Non-invasive systolic central BP was lower than the invasive systolic central BP (115±18 vs. 130±23 mmHg, P<0.001) in all patients. Non-invasive diastolic central BP was greater than the invasive diastolic central BP (67±10 vs. 63±10 mmHg, P<0.001). CONCLUSIONS: In elderly patients, AI may not be a useful marker to identify CAD.