Frequency of incidental extracardiac findings in cardiac MRI

Cardiac magnetic resonance imaging (MRI) examinations ordered for coronary artery disease, congenital heart disease, cardiomyopathy, and myocarditis are also identifying extracardiac incidental findings that otherwise would probably not be discovered. To determine the prevalence and significance of extracardiac findings, German radiologists at Humboldt-Universität zu Berlin of the Freie Universitat Berlin conducted a study whose findings they reported in the October issue of European Radiology.

The authors determined that at least one extracardiac finding is present in about every third patient having cardiac MRI. However, patient management is changed in only one patient in every 100 findings.

The 3,553 patients in the study ranged in age from two months to eighty-seven years, with a mean age of 38 years. They were predominantly male (61%). The clinical indications for ordering the exam primarily included myocarditis (27%), congenital heart disease (16%), cardiomyopathy (11%), and coronary heart disease (10%).

The radiologists at Charite Medical School reviewed the 4,376 cardiac MRI reports of these patients. They divided extracardiac findings into two categories - vascular and non-vascular, and for each, identified the location of the extracardiac finding and its specific pathology, such as being a cyst, a lesion or a nodule. Major extracardiac findings, defined as findings requiring additional diagnostic imaging or additional diagnostic or therapeutic steps, were ranked as relevant, irrelevant, or inconclusive.

Lead author Felix C. Sokolowski, MD, and colleagues reported that a total of 1,670 extracardiac findings were identified in 1,209 patients. Vascular extracardiac findings wee the most common, at 47% of the total, and predominantly involved the aorta and the pulmonary arteries. Pulmonary-related extracardiac findings represented 24%, with pleural effusion the most common, followed by changes of lung parenchyma, pulmonary nodules, and pulmonary infiltration/pneumonia.

A total of 126 major extracardiac findings were detected in 122 patients. Thirty-three were relevant and 31 inconclusive. Thirty-two malignancies were identified in 26 patients, but only three malignancies were newly identified. The overall prevalence of relevant extracardiac findings was 0.9%. The authors reported vascular indications and congenital heart disease were associated with a higher prevalence of vascular findings. Patients with cardiac masses had more major extracardiac findings, as well as older patients.

After the discovery of extracardiac findings, patient management was changed only in 1% of the cases.

REFERENCE

1. Sokolowski FC, Karius P, Rodriguez A, et al. Extracardiac findings at cardiac MR imaging: a single-centre retrospective study over 14 years. Eur Radiol. 2018;28(10):4102-4110.