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Diagnostic In-Training Exam 2003 1

Section VIII – Cardiac

314. You are shown a frontal (Figure 1A) and a lateral (Figure 1B) radiograph of a 36-year-old woman complainingof shortness of breath and palpitations. Which one of the following is the MOST likely diagnosis?

A. Aortic stenosis

B. Mitral valve disease

C. Atrial septal defect

D. Primary pulmonary hypertension

E. Total anomalous pulmonary venous return

Figure 1A

2 American College of Radiology


Figure 1B


Section VIII – CardiacQuestion #314

Findings: This standard chest radiograph of a 36-year-old female demonstrates the presence of moderatecardiomegaly. Further inspection reveals that there is left atrial and specifically left atrial appendage enlargement asevidence by a bulge along the left side of the heart just below the main pulmonary artery. There is increase in thesubcarinal angle because of left atrial dilatation. In addition, there is pulmonary vascular redistribution indicatingpulmonary venous hypertension.

Rationales:

A) Incorrect. Left atrial enlargement is not a feature of aortic stenosis. In addition, in aortic stenosis there isfrequently post-stenotic dilatation of the ascending aorta and calcification in the area of the aortic valve,findings that are lacking in this particular case.

B) Correct. Mitral valve disease is usually a sequela of rheumatic inflammation of the valve leaflets. The mitralvalve is most commonly affected, and it takes several years for clinical manifestations to appear. Decreased flowthru the mitral orifice result in progressive pulmonary venous hypertension and variable enlargement of the leftatrial chamber, particularly the appendage. Most cases present as a combination of stenosis and regurgitation,thus the generic term “mitral valve disease” should be used, particularly if there is left atrial enlargement whichis more characteristic of insufficiency.

C) Incorrect. A defect in the interatrial septum results in left to right shunting of blood and shunt vascularityconsequently. Due to decompression of the left atrium into the right side, the left atrial chamber does notenlarge in atrial septal defect.

D) Incorrect. Although the age and gender of this patient would suggest the diagnosis of primary pulmonaryhypertension, the radiographic findings do not. Left atrial enlargement is not a characteristic feature of primarypulmonary hypertension. In primary pulmonary hypertension, the central pulmonary arteries are enlarged andthere is tapering of the distal branches. The heart size remains normal except in later stages when dilatation ofthe right heart chambers develops as CO pulmonale ensues.

E) Incorrect. Depending on the level of the total anomalous pulmonary venous return, the radiographic findingsare going to vary. In type I (supra cardiac) the superior mediastinum is prominent because of enlargement ofthe brachiocephalic veins. This produces the so-called “snowman” configuration. If the venous return is directlyinto the coronary sinus or right atrium, there is enlargement of those chambers. The only type of anomalouspulmonary venous return that can produce pulmonary findings of venous hypertension similar to those ofmitral valve disease is the infradiaphragmatic type. None of the types of total anomalous venous return causeleft atrial enlargement for exclusion of that chamber constitutes the essence of those anomalies.

Citations:

Higgins CB: Essentials of cardiac radiology and imaging. Philadelphia, 1992, JB Lippincott

Amplatz K: The roentgenographic diagnosis of mitral and aortic valvular disease. Am Heart J 64; 556-566. 1962



315. You are shown two CT images (Figures 2A and 2B) of a 42-year-old patient admitted to the hospital withcomplete heart block. Which one of the following is the MOST likely diagnosis?

A. d-Transposition of the great arteries

B. l-Transposition of the great arteries

C. Truncus arteriosus

D. Coarctation of the aorta

E. Pseudocoarctation of the aorta

Figure 2A

Figure 2B



Findings: This contrast-enhanced CT demonstrates the ascending aorta anterior and to the left of the pulmonaryartery.

Rationales:

A) Incorrect. d-Transposition of the great arteries is a cyanotic condition in which the atrioventricular connectionsare concordant (right atrium connected to right ventricle and left atrium connected to the left ventricle),but there is ventriculoarterial discordance (right ventricle connected to aorta, left ventricle connected to thepulmonary artery). As a result, the ascending aorta arises anteriorly and to the right of the main pulmonaryartery.

B) Correct. In l-transposition of the great arteries there is atrioventricular discordance (right atrium connectedto left ventricle, left atrium connected to the right ventricle) and ventriculoarterial discordance (right ventricleconnected to aorta, left ventricle connected to the pulmonary artery). The hallmark of this congenital defectis the ascending aorta arising anteriorly and to the left of the pulmonary artery as this case illustrates. Thesepatients also frequently present with heart block.

C) Incorrect. Truncus arteriosus is a cyanotic heart condition characterized by lack of septation of the aortic rootand main pulmonary artery thus resulting in a common arterial trunk arising from the heart. Invariably aventricular septal defect allows mixing of blood from both ventricular chambers. Unless totally repaired ininfancy, adult survival is extremely unusual. In truncus arteriosus, the great vessels are not transposed.

D) Incorrect. In coarctation of the aorta there is a stenosis of the aorta (usually near the origin of the left subclavianartery) that produces variable obstruction to blood flow and if severe enough heart failure particularly innewborns. In adult patients, collateral vessels around the obstruction can lead to the formation of rib notching.This case demonstrates a normal diameter of the aorta with no collaterals.

E) Incorrect. Pseudocoarctation of the aorta refers to a condition in which the aortic arch is elongated producinga characteristic S-shaped deformity of the aortic arch. The relationship of the aorta and the pulmonary arteryis otherwise preserved.

Citations:

Reedy GP, Caputo GR: _Diagnosis Please. Case 15: Congenitally Corrected Transposition of the Great Arteries.Radiology 1999; 213:102



Figure 3B

316. You are shown two images of a contrast-enhanced CT scan (Figures 3A and 3B) of a 62-year-old woman whodeveloped hypotension several days after coronary by-pass graft surgery. Which one of the following is theMOST likely diagnosis?

A. Cardiac volvulus

B. Pericardial cyst

C. Constrictive pericarditis

D. Hemopericardium

E. Post-pericardiotomy syndrome

Figure 3A



Findings: Two contrast-enhanced CT images of the chest demonstrate the presence of high attenuation collectionwithin the pericardial cavity producing mass-effect and displacement of the heart to the right. n addition, Figure 3Bdemonstrates a brightly enhancing structure on the inferior surface of the heart next to a metallic surgical clip nearthe distal portion of the posterior descending coronary artery.

Rationales:

A) Incorrect. Although the heart is displaced to the right inside the pericardiac sac, there is no volvulus effect thusexcluding the diagnosis.

B) Incorrect. Pericardial cysts are usually located in the right cardiophrenic angle and are usually filled with clearfluid. Although they can attain significant size, they do not displace the heart.

C) Incorrect. Constrictive pericarditis can be excluded based on a normal thickness pericardium in this case.Pericardial constriction would in addition be very unusual to present clinically several days after surgery, as isthe case with this patient. The fluid filled pericardial cavity and heart displacement of this case are atypical forconstrictive pericarditis.

D) Correct. The presence of high attenuation material in the pericardiac sac is characteristic of hemopericardium.Pericardial hemorrhage was a result of a pseudoaneurysm formation at the distal graft anastomosis to theposterior descending branch, which explains the finding on Figure B. Associated bilateral pleural effusions andheterogeneity of the liver are the result of associated congestive changes from cardiac tamponade physiology.

E) Incorrect. In the post-pericardiotomy syndrome, clinical findings of chest pain and fever develops several daysor weeks after cardiac or pericardial injury of all kinds including trauma, catheter perforation, or surgery.Treatment usually consists of aspirin or other non-steroidal anti-inflammatory drugs.

Citations:

D. Bryk, IG Kroop, J Budow; The effect of heart size cardiac tamponade and phase of the cardiac cycle in thedistribution of pericardial fluid. Radiology 1996 93; 273-278

Spodick DH The Pericardium A Comprehensive Textbook. _Marcel Dekker, Inc. New York 1997.



Figure 4A

317. You are shown three contrast-enhanced images of a chest CT of a patient with atypical chest pain (Figures 4A,4B and 4C). Which one of the following is the MOST likely diagnosis?

A. Lipomatous hypertrophy of the interatrial septum

B. Atrial lipoma

C. Atrial myxoma

D. Bland thrombus in the right atrium

E. Atrial liposarcoma



Figure 4C

Figure 4B



Findings: Contrast-enhanced CT images through the heart demonstrate the presence of diffuse thickening of theinteratrial septum with thinning at the level of the fossa ovalis as seen on Figure 4C. The septal thickening ischaracterized by very low attenuation tissue characteristic of fat.

Rationales:

A. Correct. Lipomatous hypertrophy of the interatrial septum is characterized by deposition of non-encapsulatedfat in the interatrial septum, sparing the fossa ovalis, a characteristic feature. It can be associated witharrhythmias.

B. Incorrect. Atrial lipoma can occur in any portion of the atria including the atrial septum. However, they do notspare the fossa ovalis as this case illustrates. Lipomas consist of encapsulated mature adipose cells, can grow tosignificant size, and are considered distinct from lipomatous hypertrophy of the interatrial septum.

C. Incorrect. Atrial myxomas are soft tissue benign tumors of the heart that can be found in any chamber, but aremost commonly seen in the left atrium, attached to the interatrial septum. The fatty nature of this case excludesthe diagnosis of myxoma.

D. Incorrect. The fatty appearance of the atrial infiltration excludes the diagnosis of bland thrombus of the rightatrium.

E. Incorrect. Liposarcoma of the heart is extremely rare, and as liposarcomas at other sites is characterized bystrands of soft tissue within the fatty tumoral mass. Again, the pure fatty nature of the tumor and sparing of thefossa ovalis excludes liposarcoma as a diagnosis.

Citations:

Araoz PA, Mulvagh SL, Tazelaar HD, Julsrud PR, Bree JF; CT and MR imaging of Benign Primary CardiacNeoplasms with Echocardiographic Correlation. Radiographics 2000 20:1303-1319



Figure 5A

318. You are shown coronal CINE images in diastole (Figure 5A) and systole (Figure 5B) of a patient with chestpain. Which one of the following is the MOST likely diagnosis?

A. Type A aortic dissection

B. Syphilitic aortitis

C. Aortic stenosis

D. Aortic regurgitation

E. Atherosclerotic aortic aneurysm



Figure 5B



Findings: Cardiac cine images in diastole and systole demonstrate the presence of a focal area of dark “jetting”arising from the aortic valve during systole (Figure 5B). No other areas of signal abnormalities are seen.

Rationales:

A. Incorrect. Other than the systolic signal abnormality arising from the aortic valve during ventricular systole, theaorta has normal appearance without intimal flaps that are the hallmark of aortic dissection.

B. Incorrect. Syphilitic aortitis is a rare delayed sequela of tertiary syphilis frequently occurring 15-30 years afterthe primary infection. Most cases involve the aortic root or arch and calcifications are common. The aorticleaflets are usually spared, and aneurysms are common.

C. Correct. Aortic stenosis is usually a consequence of degeneration of a bicuspid aortic valve, a condition seen inabout 2% of the population. The presence of turbulent jetting across the aortic valve during ventricular systolemakes this the most plausible diagnosis.

D. Incorrect. Lack of signal below the aortic valve during diastole (Figure 5A) implies a competent aortic valvethus excluding regurgitation as an alternative.

E. Incorrect. The aorta does not show any aneurysm formation in this case thus excluding the diagnosis. Inaddition, atherosclerosis does not typically involve the aortic valve.

Citations:

Dominique Didier, Osman Ratib, René Lerch, and Beat Friedli. Detection and Quantification of Valvular HeartDisease with Dynamic Cardiac MR Imaging. RadioGraphics 2000 20: 1279-1299.

VB Ho and MR Prince. Thoracic MR aortography: imaging techniques and strategies. RadioGraphics 1998 18:287-309.

SA Rebergen, RA Niezen, WA Helbing, EE van der Wall, and A de Roos. Cine gradient-echo MR imaging and MRvelocity mapping in the evaluation of congenital heart disease. RadioGraphics 1996 16: 467-481

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