Dobutamine stress echocardiography: sensitivity, specificity, and predictive value for future cardiac events

We conducted a retrospective study to determine whether dobutamine stress echocardiography (DE) can be used for risk stratification of patients with known or suspected coronary artery disease (CAD). The study population consisted of 77 patients who underwent DE at our institution. The protocol consisted of an echocardiogram at baseline followed by imaging during intravenous dobutamine infusion starting at 10 micrograms/kg/min with increments of 10 micrograms/kg/min every 3 minutes to a maximum dose of 40 micrograms/kg/min. The reasons for performing DE included preoperative cardiac evaluation (30), chest pain (23), assessment of ischemia (18), and suspected restenosis (6). DE was classified according to wall motion response as normal (before and during DE), fixed abnormal (abnormal before with no change during DE), or ischemic (new wall-motion abnormality during DE). Mean duration of follow-up was 10 months. Cardiac events occurred in 14 patients. These included congestive heart failure in seven patients, myocardial infarction in six, and cardiac death in one. A normal wall-motion response (n = 40) was associated with a low incidence of cardiac events (5%), whereas 5 of 10 patients (50%) with an ischemic response had events. The risk of cardiac events was intermediate (26%) in patients with fixed abnormal wall motion. Overall sensitivity of DE for predicting future cardiac events was 85%. In 45 patients who underwent coronary angiography within 2 months of DE, the test detected CAD with a sensitivity of 71%. In conclusion, the wall-motion response during DE may be used for identifying patients at high risk for future cardiac events.