Prevalence of coronary artery disease in patients with aortic stenosis with and without angina pectoris

P with aortic stenosis often seek medical attention because of angina pectoris. Previously published studies1 have reported that about half the subjects with aortic stenosis and angina pectoris have coronary artery disease; in the other half, angina is believed to be due to markedly increased myocardial oxygen demands in the setting of inadequate myocardial perfusion. At the same time, there is disagreement about the incidence of coronary artery disease in patients with aortic stenosis who do not have angina pectoris. On the one extreme, several investigators2–5 have reported that the incidence of coronary artery disease in these subjects is ,10%, leading some of them6,7 to suggest that coronary angiography (in preparation for valve replacement) is unnecessary in these subjects. In contrast, a few investigators8–10 have shown that 25% to almost 50% of subjects with aortic stenosis but without angina pectoris have coronary artery disease. Apart from this wide disparity in results, many of these reports are limited by: (1) small numbers of patients, and (2) the inclusion of subjects with substantial aortic regurgitation. Accordingly, this study was performed to assess the incidence of coronary artery disease in a large number of subjects (.100) with isolated aortic stenosis who did not have angina pectoris. • • • We reviewed the records of all 10,203 patients who underwent cardiac catheterization at Parkland Memorial Hospital from July 1978 to July 2000. We identified 272 subjects (131 men, 141 women, aged 18 to 86 years [mean 6 SD 61 6 13]) with isolated valvular aortic stenosis (valve area #1.2 cm). Each subject underwent right and left heart catheterization and selective coronary angiography. Left ventricular and ascending aortic pressures were recorded simultaneously, from which a mean transvalvular gradient was calculated, in accordance with previously described methods.11 Cardiac output was quantitated by the Fick principle, in accordance with previously described methods,12 after which aortic valve area was calculated according to the formula of Gorlin and Gorlin.13 Coronary artery disease was defined as $70% luminal diameter narrowing of an epicardial coronary artery. For each subject, the presence (or absence) of angina pectoris was noted. In addition, the presence of hypertension (systolic pressure $140 mm Hg, diastolic pressure $90 mm Hg, or ongoing antihypertensive therapy), diabetes mellitus, hypercholesterolemia (total cholesterol $200 mg/dl or ongoing hypolipidemic therapy), and tobacco abuse was noted. All data are reported as mean 6 1 SD. Patients with and without angina pectoris were compared using the chi-square test for categorical variables and Student’s t test for continuous variables. For all analyses, a p value ,0.05 was considered significant. Of the 272 patients, 160 had angina pectoris (59%), whereas 112 did not (41%) (Table 1). Of the 160 patients with angina, 69 had coronary artery disease (43%), and 91 did not (57%). Seventy-nine of the 112 patients (71%) without angina pectoris had no coronary artery disease, but 33 of those (29%) without angina pectoris had coronary artery disease. As displayed in Table 1, the incidence of coronary artery disease was similar in patients with (43%) and without (29%) angina pectoris. The sensitivity of angina pectoris in identifying coronary artery disease was 68% (69 of 102 patients), and the specificity was 46% (79 of 170 patients). The positive predictive value was 43%, and the negative predictive value was 71%. Hyperlipidemia was more common in patients with angina pectoris (Table 1). • • • Several previously published studies have consistently reported that about half the patients with aortic stenosis and angina pectoris have coronary artery disease. In the other half (those with aortic stenosis and angina pectoris but without coronary artery disease), a myocardial oxygen supply:demand imbalance is believed to be caused by diminished coronary flow reserve in the setting of increased myocardial oxygen demand.14,15 In contrast, there is considerable heterogeneity among previously published studies concerning the incidence of coronary artery disease in subjects with aortic stenosis who do not have angina pectoris. Several investigators have reported that the incidence of coronary artery disease in these subjects is ,10%,2–5 leading some of these investigators to suggest that coronary angiography need not be performed in these patients in preparation for valve surgery. However, other investigators have reported that the incidence of coronary artery disease in this patient population is 25% to almost 50%,8–10 leading these investigators to recommend routine coronary angiography in all subjects with aortic stenosis (irrespective of the presence or absence of angina pectoris) before valve surgery. Most of these previously published studies are limited by small numbers of subjects as well as the inclusion of patients with mixed aortic valve disease (stenosis and regurgitation). Our data, obtained in almost 300 subjects with isolated aortic From the Department of Internal Medicine (Cardiovascular Division), the University of Texas Southwestern Medical Center, Dallas, Texas. Dr. Cigarroa’s address is: University of Texas Southwestern Medical Center, 5323 Harry Hines Blvd., Room CS 7.102, Dallas, Texas 75390-9047. Manuscript received October 19, 2000; revised manuscript received and accepted December 1, 2000.