Diagnostic value of dobutamine echocardiography in patients with angina-like symptoms preceding syncope

Dobutamine echocardiography was performed in 55 patients with syncope which was clinically suspected to be angina-related. We evaluated the value of using a single test, dobutamine echocardiography, in differentiating real ischemia-related from vasovagal syncope which was diagnosed by a tilt test. During testing, supraventricular arrhythmia was provoked in four (7.2%) patients. Dobutamine echocardiography identified all of six (10.9%) patients (sensitivity 100%), who were found with significant coronary stenosis by coronary angiograms. The etiology of syncope in the remaining 45 patients was investigated further by tilt testing, the findings of hypotension and bradycardia during which were compared head to head with those of dobutamine echocardiography. Tilt testing diagnosed vasovagal syncope in 31 patients, in whom only 19 (61.3%) patients developed vasovagal reflex during dobutamine echocardiography. Conclusively, dobutamine echocardiography had a high sensitivity in identifying syncope related to myocardial ischemia in patients with coronary stenosis, but a low sensitivity (61.3%), high specificity (90.5%) and high positive predictive value (81.8%) in detecting the syncope patients with angina caused by vasovagal effect.