Dobutamine stress myocardial perfusion imaging

In patients with limited exercise capacity and (relative) contraindications to direct vasodilators such as dipyridamole or adenosine, dobutamine stres s nuclear myocardial perfusion imaging (DSMPI) represents an alternative, e xercise-independent stress modality for the detection of coronary artery di sease (CAD). Nondiagnostic test results (absence of reversible perfusion de fects with submaximal stress) do occur in approximately 10% of patients. Se rious side effects during DSMPI are rare, with no death, myocardial infarct ion or ventricular fibrillation reported in three DSMPI safety reports for a total of 2,574 patients. On the basis of a total number of 1,014 patients reported in 20 studies, the sensitivity, specificity and accuracy of the t est for the detection of CAD were 88%, 74%, and 84%, respectively. Mean sen sitivities for one-, two- and three-vessel disease were 84%, 95% and 100%, respectively. The sensitivity for detection of left circumflex CAD (50%) wa s lower, compared with that for left anterior descending CAD (68%) and righ t CAD (88"/o). The sensitivity of predicting multivessel disease by multire gion perfusion abnormalities varied widely, from 44% to 89%, although speci ficity was excellent in all studies (89% to 94%). In direct diagnostic comp arisons, DSMPI was more sensitive, but less :specific, than dobutamine stre ss echocardiography and comparable with direct vasodilator myocardial perfu sion imaging. In the largest prognostic study, patients with a normal DSMPI study had an annual hard event rate less than 1%. An ischemic scan pattern provided independent prognostic value, with a direct relationship between the extent and severity of the perfusion defects and prognosis. In conclusi on, DSMPI seems a safe and useful nonexercise-dependent stress modality to detect CAD and assess prognosis. (C) 2000 by the American College of Cardio logy.