(Circulation. 1998;97:1024.)
© 1998 American Heart Association, Inc.
Images in Cardiovascular Medicine |
Use of Magnetic Resonance Imaging to Demonstrate a Fistula From the Aorta to the Right Atrium
Caroline Allum, MBBS, MRCP;
Charles Knight, MB, MRCP;
Raad Mohiaddin, MBBS, FRCR;
; Philip Poole-Wilson, MD, FRCP
From the Royal Brompton National Heart and Lung Hospital, London, UK.
Correspondence to Dr Caroline Allum, Radiology Department, Chelsea and Westminster Hospital, Fulham Rd, London SW10 9NH, UK.
A 74-year-old woman was admitted with a
1-month history of fever, malaise, cough, and anorexia. On examination,
she had the signs of mixed aortic valve disease. Blood cultures were
positive for Streptococcus viridans, and a diagnosis of
infective endocarditis was made.
The electrocardiogram showed sinus rhythm with
first-degree heart block (PR interval, 300 ms).
Transthoracic Doppler
echocardiography showed severe aortic
stenosis (gradient of 90 mm Hg) and mild aortic
regurgitation. Vegetations were present on the
calcified, disorganized aortic valve. Although there was no obvious
aortic root abscess, the possibility of the existence of a fistula from
the aorta to the right atrium was raised, with an indication of
continuous localized flow from the area of the aorta toward the
tricuspid valve. Transesophageal
echocardiography was therefore undertaken, but this
did not demonstrate a fistula. To clarify the anatomic situation before
aortic valve replacement, MRI was performed. This showed a fistula
between the aortic root and the right atrium
(Figure
). This finding was confirmed at
surgery. MRI allows detailed delineation of cardiac anatomy and
blood flow and may be helpful in resolving discrepancies raised by
other investigations.\.
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Figure 1. A, Spin-echo image in a coronal plane showing a
fistula (arrow) between the aortic root and the right atrium. B,
Diastolic image selected from cine gradient echo images
acquired in a plane similar to A. A turbulent jet extends from the
aortic root into the body of the right atrium (arrow). C, Corresponding
systolic (left) and diastolic (right) velocity
maps. Cranial flow velocity in the ascending aorta is seen in black,
and caudal velocity through the fistula is seen in white (arrow). In
addition, the systolic image shows a jet distal to the
stenotic aortic valve. 1 indicates ascending aorta; 2, right
atrium; 3, left ventricle; and 4, pulmonary trunk.
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Footnotes
The editor of Images in Cardiovascular Medicine is Hugh A. McAllister, Jr, MD, Chief, Department of Pathology, St Luke's Episcopal Hospital and Texas Heart Institute, and Clinical Professor of Pathology, University of Texas Medical School and Baylor College of Medicine.
Circulation encourages readers to submit cardiovascular images to Dr Hugh A. McAllister, Jr, St Luke's Episcopal Hospital and Texas Heart Institute, 6720 Bertner Ave, MC1-267, Houston, TX 77030.
