Extra-cardiac findings on coronary computed tomography scanning

Background: Cardiac computed tomography scans include several extra-cardiac structures such as mediastinum, lung parenchyma and upper abdominal organs. A variety of abnormalities in those structures might be clinically important and in some cases might explain the patient's complaints. Objectives: To analyze consecutive CCT examinations for the prevalence and clinical significance of extra-cardiac findings. Methods: Cardiac CT scans of 134 sequential patients (104 males, 30 females) aged 20-77 (mean 54 years) with suspected coronary artery disease were prospectively and independently reviewed by a consensus of two radiologists for the presence of lung, mediastinal, pleural, upper abdominal and skeletal abnormalities. CT scans with extra-cardiac abnormalities were divided into two groups: group A - defined as "clinically significant" or "potentially significant findings" - consisted of patients requiring further evaluation or follow-up, and group B - "clinically non-significant findings." Results: Extra-cardiac abnormalities were found in 103 of the 134 patients (76.8%). Group A abnormalities were found in 52/134 patients (39%), while group B abnormalities were seen in 85/134 (63%). The most common abnormalities in group A were non-calcified lung nodules (> 4 mm) noted in 17/134 patients (13%), followed by enlarged mediastinal lymph nodes (> 10 mm) in 14/134 (10%), diaphragmatic hernia (2 cm) in 12/134 (9%), moderate or severe degenerative spine disease in 12/134 (9%), and emphysema and aortic aneurysm in 6 patients each (4.5%). A malignant lung tumor was noted in one patient. Conclusions: There is a high prevalence of non-cardiac abnormalities in patients undergoing CCT. Clinically significant or potentially significant findings can be expected in 40% of patients who undergo CCT, and these will require further evaluation and follow-up. The reporting radiologist should be experienced in chest imaging.