Background: Left bundle branch blockage (LBBB) is a strong predictor of cardiovascular mortality. Non-invasive tests such as exercise-stress testing and scintigraphy studies have no diagnostic value for diagnosis of coronary artery disease (CAD) in patients with LBBB.
Objective: To study the role of dobutamine stress echocardiography (DSE) in identification of CAD in patients with LBBB.
Methods: Thirty patients (19 men and 11 women, mean age 60 +/- 8 years) with permanent, complete LBBB were studied prospectively with DSE and coronary angiography.
Results: Results of DSE were compared with results of coronary angiography for left anterior descending artery and either left circumflex or right coronary artery territories, or both. Significant CAD was found in left anterior descending coronary arteries in 11 patients by coronary angiography; nine of whom were identified by DSE. Significant left circumflex or right coronary artery disease, or both, was found in nine patients; eight of whom were identified by DSE. The sensitivity, specificity and accuracy of DSE for identifying CAD in left anterior descending coronary artery territory were 82, 95 and 90%, respectively. For identifying CAD in the circumflex and right coronary artery territories sensitivity, specificity and accuracy were 88, 96 and 93%, respectively.
Conclusion: We concluded that DSE is a very sensitive, specific and accurate non-invasive test for identification of CAD, both in left anterior descending and in left circumflex and right coronary artery territories of patients with LBBB.