Use of Magnetic Resonance Imaging to Demonstrate a Fistula From the Aorta to the Right Atrium
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.\.
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.
- Copyright © 1998 by American Heart Association