Usefulness of high functional capacity in patients with exercise-induced ST-depression to predict a negative result...

Although exercise electrocardiography (ExECG) is commonly used to detect coronary artery disease, the diagnostic accuracy and reliability of positive (ischemic) results of ExECG in low- and intermediate-risk populations are limited. Accordingly, many patients with positive results of ExECG undergo secondary evaluation using noninvasive stress imaging such as exercise echocardiography. Functional capacity is a strong predictor of prognosis and, indirectly, of high-risk coronary artery disease. It was hypothesized that high functional capacity in patients with positive results of ExECG would predict (1) negative results on subsequent exercise echocardiography and (2) a low risk for late mortality. Results were analyzed in 104 consecutive patients (79 men, 25 women; mean age 49 years, range 27 to 76) referred for exercise echocardiography after positive results of ExECG with a treadmill workload of > or =10 METs. Late all-cause mortality was also determined in these patients. Exercise echocardiographic results were negative in 93% of patients (97 of 104; 92% of men [73 of 79] and 100% of women [25 of 25]) and positive in 7% (7 of 104). During a mean follow-up period of 7.2 +/- 1.9 years, there was 1 death. In conclusion, high functional capacity in patients with positive results of ExECG is associated with negative exercise echocardiographic results in most patients and very low late mortality. Patients with ischemic ST-segment response on ExECG who achieve workloads of > or =10 METs infrequently require additional noninvasive or invasive evaluation.