Extracardiac Findings in Cardiac Computed Tomographic Angiography in Patients at Low to Intermediate Risk for Coronary Artery Disease

PURPOSE: To evaluate the prevalence, clinical significance, interobserver agreement, and follow-up of extracardiac findings on coronary computed tomographic angiography (CTA). METHODS: A prospectively recruited cohort of 80 patients at low to intermediate risk of having coronary artery disease underwent CTA with field of view imaging from lung apices to upper abdomen. Two staff radiologists read each scan independently. Scans read by reader no. 1 were read as part of routine clinical practice, and the findings were subsequently reclassified to potentially significant, as defined by requiring clinical or radiologic follow-up, and insignificant by a separate observer, whereas reader no. 2 retrospectively read and autonomously classified the findings as potentially significant or insignificant. RESULTS: Reader no. 1 found 7 potentially significant findings in 7 patients and 33 insignificant findings in 29 patients. Reader no. 2 found 10 potentially significant findings in 10 patients and 59 insignificant findings in 42 patients. Inter-rater agreement was moderate (kappa = 0.49; 95% confidence interval, 0.31-0.67) for the presence vs the absence of extracardiac findings and moderate (kappa = 0.52; 95% confidence interval, 0.15-0.89) for the presence of potentially significant extracardiac findings. The most common potentially significant finding was possibly malignant lung nodule (n = 6 [reader 1], 4 [reader 2]). Four patients with potentially significant findings received follow-up imaging, and 1 patient underwent biopsy, which was complicated by pneumothorax. No diagnoses of malignancy were made. CONCLUSIONS: Extracardiac findings are frequent and moderately reproducible, however, in this study, not associated with clinical benefit. Large prospective studies are required to establish whether reporting of extracardiac findings is associated with improved patient outcomes.