Discrepancies in Measurement of the Thoracic Aorta: JACC Review Topic of the Week.

Clinicians often encounter discrepant measurements of the ascending aorta that impede, complicate, and impair appropriate clinical assessment-including key issues of presence or absence of aortic growth, rate of growth, and need for surgical intervention. These discrepancies may arise within a single modality (computed tomography scan, magnetic resonance imaging, or echocardiography) or between modalities. The authors explore the origins and significance of these discrepancies, revealing that some "truth" usually underlies all the discrepant measurements, which individually look at the ascending aorta with different perspectives and dimensional definitions. The authors conclude with a practical "question and answer" section that addresses common specific issues in interpretation and management of patients in the real-world setting.