Coronary computed tomography angiography in patients with suspected coronary artery disease and discordant findings on exercise stress echocardiography.

PURPOSE: Exercise stress echocardiography (ExE) includes assessment of regional wall motion and EKG changes and, not uncommonly, discordant results are observed. Though stress induced wall motion abnormalities are widely considered positive for presence of ischemia, EKG-only positive studies are dismissed as equivocal/false positive, in which case, further evaluation is appropriate.

METHODS

Patients who had undergone a clinically indicated ExE and subsequent coronary CT angiogram (CCTA) within one month were identified. They were categorized based on the discordant results of the echocardiographic and electrocardiographic components of the study (EKG+/ECHO-, EKG-/ECHO+). The CCTA results were classified using CAD-RADS 2.0. CT fractional flow assessment was performed for 30-90% stenosis lesions.

RESULTS

197 patients with discordant ExE results were identified (EKG+/ECHO- n = 159, EKG-/ECHO + n = 38). 35.2% of the EKG+/ECHO- group were classified as CAD-RADS 3 or greater (28.9% left anterior descending, 12.6% left circumflex, and 15.1% right coronary artery moderate/severe stenoses). Of the EKG-/ECHO + patients, 23.7% were classified as CAD RADS 3 or greater (15.8% left anterior descending, 5.3% left circumflex, and 10.5% right coronary artery moderate/severe stenoses). No statistically significant difference was observed between the two groups in the overall degree of coronary artery disease.

CONCLUSIONS

Discordant ExE results with ST segment depressions during exercise without regional wall motion abnormalities (EKG+/ECHO-) and discordant ExE results without ST segment changes with stress-induced regional wall motion abnormalities (EKG-/ECHO+) are both associated with a clinically relevant burden of coronary artery disease, without a statistically significant difference in the degree or severity between the two groups.