Correlation of Treadmill Stress Test with Coronary Angiography to Predict Coronary Artery Disease in Males versus Females

Abstract

Background Treadmill stress test (TMT) is the most commonly performed stress test for diagnosis of coronary artery disease (CAD) in outpatient setting. The present study was conducted to find correlation of TMT with coronary angiography (CAG) in males versus female patients. Methods Total 422 patients who had undergone CAG and TMT were enrolled in present study. TMT test was done using Bruce protocol, and results were classified as inconclusive, low, intermediate, and high probability for inducible ischemia. Results Of 422 patients enrolled in the present study, 290 (69%) were males and 132 (31%) were females. Clinical presentation was angina on exertion CCS class II–III in 302 (71.6%) patients and angina equivalent in 124 (29.4%) patients. Out of these, 211 (50.2%) were diabetic and 308 (72.9%) were hypertensive. TMT was inconclusive, low, intermediate, and high probability for inducible ischemia in 35 (8.2%), 40 (9.7%), 19 (4.5%), and 328 (77.7%) patients, respectively. CAGs were normal in 149 (35.4%) patients and abnormal in 273 (64.6%) patients. Out of 328 patients with strongly positive TMT, 104 (31.7%) had normal coronaries, 56 (17%) had mild CAD, while 75 (22.8%) had SVD. LMCA disease, DVD, and TVD were found in 5 (1.5%), 48 (14.6%), and 40 (12.1%) patients, respectively. Of 132 female patients, 70 (53%) were found to have CAD and 62 (47%) had normal coronaries on CAG. Of 290 males, 241(83.1%) were found to have CAD and 49 (16.8%) had normal coronaries on CAG. Positive predictive value (PPV) in females was 53% and in males was 83%. Subgroup analysis showed that if there was high-probability TMT along with older age (p < 0.00), male sex (p < 0.01), and diabetes (p < 0.00), chances of having CAD were more. Conclusion PPV of positive TMT in female is 53% and in male is 83%. High-probability TMT along with the older age, male sex, and presence of diabetes mellitus (DM) makes the probability of having CAD is high.