Transesophageal Echocardiographic Recognition of an Unusual Complication of Aortic Valve Endocarditis

CASE REPORTS

Transesophageal Echocardiographic Recognition of a Fistula Between a Coronary Artery and the Left Atrium Toshiyuki Oniki, MD, Yuji Hashimoto, MD, Wulin Aerbajinai, MD, Akihiro Hata, MD, Akihiko Matsumura, MD, Masayoshi Iwakami, MD, Fujio Numano, MD, and Masayasu Hiraoka, MD, Tokyo, Japan

A 58-year-old woman with a prosthetic mitral valve and an anomalous single coronary artery received transesophageal echocardiography and was found to have a coronary artery-to-Ieft atrium fistula. Because of its superior imaging quality, transesophageal color Doppler method is a useful diagnostic procedure. (J AM Soc ECHOCARDIOGR 1992;5:628-30.)

Echocardiography has been recognized as a useful noninvasive diagnostic procedure for the detection of a coronary artery fistula. 1,2 Transesophageal Doppler echocardiography provides another means of assessing coronary artery morphology by providing a high-quality image. We report a fistulous connection between a coronary artery and the left atrium identified by transesophageal echocardiography in a patient with a single left coronary artery and a prosthetic mitral valve.

systole) suggesting the presence of a coronary arteryto-left atrium fistula (Fig. 1, A). A more careful color Doppler examination demonstrated that a coronary vessel between the left atrium and the ascending aorta had abnormal flow originating from it (Fig. 1, B). We thus concluded that she had a coronary artery-to-left atrium fistula. Follow-up coronary arteriography also demonstrated a fistulous connection between the sinus node artery and left atrium. Her right coronary artery originated from the left anterior descending artery.

CASE REPORT

DISCUSSION

A 58-year-old woman received biplane transesophageal echocardiography (Toshiba SSH160A, PEF507SB, Tokyo, Japan) to evaluate the function of her prosthetic valve 7 years after her mitral valve was replaced because of mitral stenosis with left atrial mural thrombus formation. She also had been diagnosed as having a rare minor anomaly, a single coronary artery (Group LIIA by the system of Lipton et al. 3 ) before surgery. Coronary artery fistula was not detected by coronary arteriography and aortography at that time. Transesophageal echocardiography showed an abnormal flow signal in the left atrium and the flow pattern (which had a continuous profile with flow velocity augmentation during late diastole and early From the Third Department ofIntemal Medicine and Department of Cardiovascular Diseases, Tokyo Medical and Dental University. Reprint requests: Toshiyuki Oniki, MD, Third Department of Internal Medicine, Tokyo Medical and Dental University, School of Medicine, 1-5-45 Yushima, Bunkyo-ku, Tokyo 113, Japan. 27/1/40418

628

Coronary artery fistulae have been described as the result of congenital anomalies, trauma, various coronary artery diseases, and atrial thrombi. 4 ,5 Our patient has a congenital single coronary artery anomaly, as well as history of mitral stenosis and cardiac surgery. Although the cause of her coronary artery fistula cannot be unequivocally determined, a congenital origin is unlikely because no fistula had been detected by the coronary arteriography and aortography performed before the mitral valve replacement surgery. We believe that the fistula may have developed as a result of neovascularity after the thrombectomy of her left atrial mural thrombus. The echocardiographic diagnosis of a coronary artery fistula is usually based on a two-dimensional visualization of a dilated coronary artery and the Doppler detection of an abnormal shunt flow. 1,2,6 However, it is known that some fistulae show none of these findings with transthoracic approach.2 In our patient, we could detect neither a dilated coronary artery nor shunt flow with conventional transthoracic

Volume 5 Number 6 November-December 1992

Coronary artery-to-left atrial shunt 629

Figure 1 A, Sagittal plane imaging from upper esophagus shows abnormal flow in left atrium (arrow). The abnormal flow has a high velocity demonstrated by pulsed-wave Doppler recording (left upper panel). M -mode recording (left lower panel) demonstrates the continuous profile of the abnormal flow. Some flow in the wall between the left atrium and ascending aorta can be seen during late diastole-to-early systole period (small arrowheads). B, A coronary vessel between the left atrium and the ascending aorta can be identified by color-flow mapping (small arrowheads). The abnormal flow appears to originate from that vessel (arrow). LA, Left atrium; Ao, aorta; RA, right atrium; PA, pulmonary artery.

630 Oniki et al.

echocardiography. However, a coronary artery fistula emptying into the left atrium, but without significant coronary artery dilatation, was clearly identified with transesophageal echocardiography. Transesophageal echocardiography yields a superior image of the cardiac structures because of their proximity to the esophagus, making it possible to use a higher-frequency transducer (5 MHz) than feasible with the transthoracic approach. 6,7 The present case also demonstrates the superiority of transesophageal echocardiography, especially with color-flow mapping, for delineating the cardiac structures and for detecting any abnormal flow and suggests that transesophageal echocardiography adds a new modality for the evaluation of coronary artery fistula.

Journal of the American Society of Echocardiography

2. Miyatake K, Okamoto M, Kinoshita N, et al. Doppler echocardiographic features of coronary arteriovenous fistula. Complementary roles of cross sectional echocardiography and the Doppler technique. Br Heart J 1984;51 :508-18. 3. Lipton MJ, Barry WH, Obrez I, Silverman JF, Wexler L. lsolared single coronary artery: diagnosis, angiographic classification, and clinical significance. Radiology 1979;130:39-47. 4. Rittenhouse EA, Dory DB, Ehrcnhaft JL. Congenital coronary artery-cardiac chamber fistula. Ann Thorac Surg 1975;20:46885. 5. Blanche C, Chaux A, Buchbinder N, O'Connor L. Acquired left coronary artery to left atrium fistula: unusual complication of aottocoronary bypass. J Cardiovasc Surg 1986;27:231-3. 6. Rubin DA, Zaki AM, Zaghlol S, Abdala S, FaJuny AR, Ziady G. Visualization of coronary artery fistula with transesophageal echocardiography. J AM Soc ECHOCARDIOGR 1992;5:173-5. 7. Richardson SG, Weintraub AR, Schwarz SL, et al. Biplane rransesophageaJ echocardiography utilizing transverse and sagittal imaging planes: technique, echo-anatomic correlations, and display approaches. Echocardiography 1991;8:293-309.

REFERENCES 1. Chen CC, Hwang B, Hsiung MC, er al. Recognition of coronary arterial fistula by Doppler 2-dimensional echocardiography. Am J Cardiol 1984;53:392-4.

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