Detection of coronary artery disease in aortic stenosis by exercise gated nuclear angiography

Abstract

Because the clinical diagnosis of coronary artery disease (CAD) in the presence of aortic stenosis (AS) is difficult, the value of exercise gated nuclear angiography in detecting CAD in 33 patients with AS was assessed. Exercise left ventricular (LV) ejection fraction (EF) and wall motion analysis were evaluated after symptom-limited supine cycle ergometer exercise. Sixteen patients had severe AS (valve area 0.8 cm2 or less). Thirteen had significant associated CAD (50% or greater reduction in luminal diameter of 1 major coronary artery). Twenty patients had normal coronary arteriograms. All 10 patients with mild to moderate AS and normal coronary arteries had normal nuclear studies. Patients with CAD, regardless of the severity of AS, had a decrease in LVEF during exercise (12 of 13 patients) and regional wall motion abnormalities (11 of 13 patients). Abnormal exercise gated nuclear ventriculographic studies occurred in the absence of CAD in 10 of 20 patients, and all had severe AS (mean aortic valve area 0.8 cm2 or less, range 0.4 to 0.8). Ten had an abnormal LVEF response to exercise and 7 had exercise-induced abnormal wall motion. These findings suggest that the presence of an abnormal LVEF, whether in conjunction with an abnormal wall motion analysis, is indicative of further invasive evaluation; conversely, in those patients with a normal response of LVEF and normal wall motion during exertion, invasive studies may be safely deferred.