Low negative predictive value of dobutamine stress echocardiography before abdominal aortic surgery.

BACKGROUND According to previous studies, a negative dobutamine stress echocardiography (DSE) test before major vascular surgery indicates that postoperative myocardial necrosis is very unlikely. We believe that the use of new cardiac troponin assays which can detect small amounts of myocardial necrosis results in a lower DSE negative predictive value for myocardial necrosis. METHODS A total of 418 consecutive patients were screened using the ACC/AHA Guideline for Perioperative Cardiovascular Evaluation for Noncardiac Surgery before scheduled abdominal aortic surgery. Of these 143 met ACC/AHA criteria for non-invasive testing and underwent DSE. Patients with a negative DSE were deemed to be fit for surgery. A positive DSE led to a coronary angiogram. DSE was negative in 110 (77%) and positive in 33 (23%) patients. Myocardial necrosis was monitored up to the third postoperative day by daily cardiac troponin I (cTnI) measurement and a daily 12-lead ECG. RESULTS Coronary angiography showed artery stenosis in 27 (84%) of 32 patients with a positive DSE. The negative predictive value of DSE for cTnI elevation was 92.7% (95% CI 86.2-96.8%). This was significantly lower than the lowest value of negative predictive value for myocardial necrosis assessed in previous studies. CONCLUSION A negative DSE prescribed before scheduled aortic surgery according to ACC/AHA guidelines does not rule out postoperative myocardial necrosis.