RESUMO
Exercise testing is a well known means of evaluating patients with unstable angina, but in recent years, alternative methods have been proposed. We prospectively compared standard exercise testing with dobutamine electrocardiographic stress testing for patients who were admitted with a diagnosis of unstable angina. A total of 43 patients were studied, divided into two different groups, according to the presence (group A n = 26) or absence (group B n = 17) of a previous history of coronary artery disease and/or electrocardiographic changes compatible with ischemia on admission. Dobutamine electrocardiographic stress testing was performed in a standard manner at 3 +/- 1 days after admission in group A and at 16 +/- 8 hours after admission in group B. Exercise testing was performed, on average 5 +/- 1 days following the event in group A and 2 days after admission in group B. Agreement between both tests was observed in 39 (91%) cases, Kappa value: 0.81. The dobutamine test predicted the result of the exercise test with a sensitivity of 79% (95% CI 54-90), and a specificity of 100% (95% CI 86-100), with a positive predictive value of 100% and a negative predictive value of 86%. It can be concluded that dobutamine electrocardiographic stress testing is an objective and reliable procedure that accurately predicts the results of standard exercise testing in patients with a diagnosis of unstable angina. If this result were confirmed with a greater number of patients, it would be a good option for definitive diagnosis and risk stratification, in addition to being inexpensive and easy to perform. It can also be particularly useful for patients who cannot perform exercise.