Case 71: Ebstein Anomaly

Assessment of right heart dilatation with magnetic resonance imaging and multidetector computed tomography angiography: spectrum of disease findings

Right heart chamber enlargement can be caused by a diverse and heterogeneous group of conditions with highly varied clinical symptoms and signs. An appreciation of the pathophysiology, causes, and imaging features of right heart enlargement is paramount in recognizing and potentially ameliorating the development of right heart dysfunction or adverse cardiac events. Chest x-ray and transthoracic echocardiography have traditionally been, and still are, the mainstay in initial evaluation of right heart dilatation; however, recent advances in both multidetector computed tomography and cardiovascular magnetic resonance imaging now permit a comprehensive assessment of the causes and consequences of right heart dilatation.

[Congenital heart disease in adults: the contribution of multidetector CT]

Congenital heart disease is relatively common among adults. Patients' conditions have generally been diagnosed previously and imaging tests are requested for follow-up or for complications of the anomaly or of its surgical correction. Classically, these patients were studied with echocardiography and cardiac catheterization, but multidetector CT and magnetic resonance imaging have changed the approach because these techniques show the anatomy of heart defects and their correction very clearly. We emphasize the importance of multidetector CT as a complementary technique for the study of congenital heart disease that is newly discovered in adults or for the follow-up of congenital heart disease that was surgically corrected during childhood. When vascular anomalies are present outside the heart or after palliative surgery, multidetector CT shows anatomical details that are difficult or impossible to see with echocardiography. We also emphasize the frequent association between pulmonary hypertension and congenital heart disease that can debut in adults.

Classic imaging signs of congenital cardiovascular abnormalities

Cardiovascular imaging is a rapidly evolving field that requires familiarity with the appearances of pediatric and adult cardiovascular diseases on chest radiographs as well as images obtained with computed tomography, magnetic resonance imaging, and angiography. To accurately identify congenital abnormalities affecting the heart and vessels of the thorax, radiologists must recognize the imaging features and understand their pathophysiologic origin. The cardiovascular imaging signs of congenital anomalies that are most often seen in radiologic practice include the egg on a string (seen in transposition of the great arteries), snowman (total anomalous pulmonary venous return), scimitar (partial anomalous pulmonary venous return), gooseneck (endocardial cushion defect), figure of three and reverse figure of three (aortic coarctation), boot-shaped heart (tetralogy of Fallot), and box-shaped heart (Ebstein anomaly).