Diagnostic Value of Simultaneous Brachial and Ankle Blood Pressure Measurements for the Extent and Severity of Coronary Artery Disease as Assessed by Myocardial Perfusion Imaging

BACKGROUND: Although the simultaneous measurement of brachial and ankle blood pressure is a simple method of evaluating atherosclerosis, its diagnostic value for coronary artery disease (CAD) is undetermined. METHODS AND RESULTS: To evaluate the diagnostic value of ankle-brachial pressure index (ABI) and brachial-to-ankle pulse wave velocity (baPWV), 334 consecutive patients with suspected CAD were evaluated. Patients with a previous myocardial infarction or coronary intervention were not included. The magnitude of myocardial ischemia was evaluated by myocardial perfusion imaging. Using a 20-segment model, the percent of ischemic segments to total segments was expressed as %myocardium ischemic. In patients with < or =1, 2 and > or =3 coronary risk factors, %myocardium ischemic was 2.7+/-0.4, 4.0+/-0.5, 7.9+/-0.8%, respectively (p<0.0001 for trend). Performing ABI with a cutoff of 1, the %myocardium ischemic was similar in patients with < or =1 or 2 risk factors. In patients with > or =3 coronary risk factors, however, an ABI <1 reflected greater %myocardium ischemic than an ABI > or =1 (10.1+/-1.3, 6.6+/-1.0%; p=0.03). No such additional value was observed with baPWV. CONCLUSIONS: The addition of simultaneous brachial and ankle blood pressure measurements will help further stratify patients with multiple risk factors. Although this approach is simple, it facilitates the identification of high-risk patients who require aggressive treatment because >10% myocardium ischemic is regarded as a scintigraphic indicator for coronary revascularization.