Utility of stress echocardiography in identifying significant coronary artery disease in patients with left bundle-branch block.
OBJECTIVE
The aim of the study was to determine the utility of stress echocardiography for identification of significant coronary artery disease (CAD) in higher-risk patients with an underlying left bundle-branch block (LBBB).


METHODS
Patients with LBBB undergoing stress echocardiography were divided into 2 groups: group 1 (no history MI), group 2 (history MI). Positive stress echocardiograms were compared with the presence of >50% luminal-diameter stenosis during coronary angiography. During the follow-up (FU) period, cardiac events were determined for hard and soft endpoints.


RESULTS
Sixty consecutive patients with LBBB underwent stress echocardiography. Twenty-eight patients had a positive stress echocardiogram (20 group 1; 8 group 2). Nineteen of these patients underwent coronary angiography (14 group 1; 5 group 2). In group 1, regional wall motion abnormality (RWMA) correlated with coronary anatomy in only 5 patients, while in group 2, RWMA correlated with coronary anatomy in only 2 patients. There were 12 false positives, with echocardiographic abnormalities identified. The positive predictive values in groups 1 and 2 were 35.7% and 40%, respectively. During the FU period, there was 1 mortality, 2 MI, 2 coronary revascularizations, and 6 hospitalizations (2 chest pain, 1 CHF, 3 coronary angiography). The negative predictive value for hard endpoints was 83%.


CONCLUSIONS
Stress echocardiography has a poor positive predictive value to identify significant angiographic CAD in higher-risk patients with LBBB; however, the negative predictive value for hard ischemic events is similar to patients without LBBB.
Lewis
William R
WR
Division of Cardiovascular Medicine, Department of Internal Medicine, University of California Davis School of Medicine, Sacramento, California 95817, USA. william.lewis@ucdmc.ucdavis.edu
Ganim
Rick
R
Sabapathy
Rajendran
R
D000368:Aged; D002037:Bundle-Branch Block / Q000150:complications* / Q000503:physiopathology; D003327:Coronary Disease / Q000150:complications / Q000000981:diagnostic imaging* / Q000503:physiopathology; D003937:Diagnosis, Differential; D025401:Echocardiography, Stress; D004562:Electrocardiography; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008875:Middle Aged; D009200:Myocardial Contraction; D011379:Prognosis; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D012720:Severity of Illness Index