Cover Image: Giant coronary-cameral fistula compressing the heart
On-Hing Kwok1, Wing-Hing Chow1, and Shui-Wah Chiu2
1 Division of Cardiology,University Department of
Medicine, Grantham Hospital, Hong Kong
2 University Department of Cardiothoracic Surgery, Grantham
Hospital, Hong Kong
A 36-year-old man, who underwent successful surgical ligation of his congenital right coronary-cameral fistula to the left ventricle some 12 years earlier, presented with insidious onset of dyspnoea on exertion and with oedema. He first presented with a continuous murmur and chest discomfort at childhood. Past operation record revealed that the right coronary artery (RCA) was huge with a diameter of 3 cm, running in its usual course, and turned abruptly inwards entering the left ventricle at the crux just behind the posterior mitral valve leaflet. There was a palpable thrill along the vessel before operation. The distal opening of the fistula was then ligated surgically and the thrill disappeared, although the vessel remained the same in diameter. There was no heart murmur during the current assessment. Chest X-ray showed increase in cardiothoracic ratio. Transoesophageal echocardiogram revealed a dilated right coronary ostium and Sinus of Valsalva, with moderate aortic regurgitation. (Panel C) A remnant of the coronary-cameral fistula was present with a diameter of 7.5 cm and compressing on the right heart. There was mural thrombus and a lumen with spontaneous echo contrast, suggestive of sluggish blood flow or stasis. (Panel D) There was no abnormal turbulent entry into the cardiac chambers. However, the mass effect impeded the diastolic filling of the right heart. There was exaggerated interdependence of the septum during respiration, suggestive of a constrictive physiology. The patient also had a history of anaphylaxis to radio-contrast, which precluded further evaluation of the anomaly by coronary angiogram or contrast CT scan. Magnetic resonance imaging was performed and confirmed the presence of the giant coronary-cameral fistula, which measured up to 8.9 cm across, compressing the right heart. (Panel A and B) Mural thrombus was present with a patent lumen of up to 5 cm. In view of the mass effect of the fistula and constrictive physiology, surgical excision was contemplated. It is rather unusual for coronary-cameral fistula to have progressive enlargement after successful surgical repair. Essentially, the fistula behaved like a blind-ended aneurysm, which failed to clot up completely but continued to expand slowly over time. Perhaps, follow-up imaging is warranted for monitoring the progress of large coronary-cameral fistula even after successful closure.
Figure legend:
Panel A: Magnetic resonance imaging (MRI) of the heart showed the
remnant of a giant right coronary-cameral fistula with mural
thrombus
Panel B: MRI of the heart showing compression of right atrium and
ventricle by the coronary-cameral fistula
Panel C: Transoesophageal echocardiogram (TEE) of the heart. =
Longitudinal view showed dilated right coronary ostium a Sinus of
Valsalva.
Panel D: TEE (four-chamber view) showed compression of the right
heart by the coronary-cameral fistula. Spontaneous echo contrast and
colour flow was seen inside the lumen, suggestive of sluggish blood
flow. Mural thrombus was present.
RA, right atrium; RV, right ventricle; LA, left atrium; LV, left ventricle.
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