[The role of the echo-dipyridamole test in the diagnosis of coronary disease in patients with associated aortic stenosis].

BACKGROUND: Coronary vasodilator reserve is often significantly impaired in patients with aortic stenosis by several mechanisms: coronary artery disease, left ventricular hypertrophy, increase in cardiac chamber stiffness. The aim of this study was to evaluate the feasibility and the diagnostic accuracy of the dipyridamole echocardiography test in the diagnosis of coronary artery disease in patients with aortic stenosis. METHODS: Forty patients (26 males, 14 females, mean age 69 +/- 8.9 years) with aortic stenosis (mean valve area 0.7 +/- 0.3 cm2 calculated by the continuity equation) were studied by two-dimensional echocardiography during dipyridamole infusion up to 0.84 mg/kg over 10 min. Wall motion was graded for each segment as normal, hypokinetic, akinetic and dyskinetic. Dipyridamole echocardiography was considered positive for ischemia if wall motion in at least one segment worsened by at least one degree point level compared to wall motion at rest. All patients underwent coronary angiography (mean time after dipyridamole echocardiography 7 +/- 3 days). The chi 2 test and Student's t-test for paired data were used; a p value of or = 1 mm during dipyridamole infusion; 12 patients experienced angina during the test. Angiography showed a significant coronary stenosis in 10 patients. Dipyridamole echocardiography sensitivity was 80%, specificity was 96%; specificity of ST segment downsloping and angina were 63 and 76% respectively. CONCLUSIONS: Dipyridamole echocardiography in patients with aortic stenosis is safe and feasible with good sensitivity and better specificity. Our study suggests also that dipyridamole echocardiography test is able to rule out patients with aortic stenosis and coronary artery disease as opposed to those with angina without organic stenosis of the coronary vessels.