A 75-year-old woman was admitted to our hospital for surgical myocardial revascularization. Coronary angiography showed an anomalous arterial branch originating from the circumflex coronary artery with an unclear and unusual anatomic course (Fig. 1).
Fig. 1 Coronary angiography. Selective angiography of the left main coronary artery displays an anomalous vessel originating from the proximal segment of the circumflex coronary artery. F = fistula; LAD = left anterior descending coronary artery; LCx = left circumflex coronary artery
A 64-slice computed tomographic scan (MSCT; LightSpeed VCT XT™; GE Healthcare, a division of the General Electric Company; Fairfield, Conn), using 3-dimensional volume-rendered reconstruction, showed this vessel to be an arterio–arterial fistula between the left circumflex coronary artery and the left atrium. Moreover, the fistula had a double communication with the atrium, with 2 separate outflows: the 1st emptied into the left atrial roof and the 2nd, at the end of the fistula, emptied into the left superior pulmonary vein at its origin (Fig. 2).
Fig. 2 Sixty-four-slice computed tomography. Three-dimensional, volume-rendered reconstruction shows the course of the arterio–arterial fistula. The vessel runs from the proximal circumflex coronary artery to the origin of the left superior pulmonary vein. The fistula has a double communication with the atrium; an intermediate outflow is pinpointed (*) at the level of the left atrial roof. F = fistula; LAD = left anterior descending coronary artery; LCx = left circumflex coronary artery
Coronary artery bypass grafting was performed. Upon opening the pericardium, we confirmed the location and the course of the fistula. Because the size of the anomalous vessel was insubstantial, and the patient had never experienced any related symptoms, we left the 2 communications open. The operation was concluded in the routine way and presented no complication.
Comment
The incidence of congenital coronary fistulae is about 0.5%.1 Only 10% open into the left heart chambers, and most of those (80%) enter the left atrium. Heart auscultation reveals a continuous murmur; cardiomegaly or plethora may be present. Diagnosis is usually confirmed by means of cardiac catheterization. Possible sequelae include pulmonary hypertension, cardiac failure, endocarditis, spontaneous rupture, thrombosis, and distal ischemia. When clinically necessary, fistulae are usually treated with surgical or percutaneous closure.2
Although coronary angiography is, to date, the gold standard for the evaluation of coronary artery disease, multislice computed tomography provides an emerging and promising technique for the study of cardiovascular pathologic conditions, including coronary anomalies.3 Three-dimensional reconstruction of the scan enabled us to see the exact anatomy without exposing the patient to repeated radiation or to an additional contrast load.
This case report is one of the few published wherein such a coronary anomaly has been diagnosed using computed tomographic scanning.3,4 In our department, multislice computed tomography is a primary tool for the investigation of congenital heart anomalies, because it provides information essential both to diagnosis and to the choice of a therapeutic approach.
References
- 1.Cademartiri F, Runza G, Luccichenti G, Galia M, Mollet NR, Alaimo V, et al. Coronary artery anomalies: incidence, pathophysiology, clinical relevance and role of diagnostic imaging [in Italian]. Radiol Med 2006;111(3):376–91. [DOI] [PubMed]
- 2.Reidy JF, Anjos RT, Qureshi SA, Baker EJ, Tynan MJ. Transcatheter embolization in the treatment of coronary artery fistulas. J Am Coll Cardiol 1991;18(1):187–92. [DOI] [PubMed]
- 3.Shabestari AA, Akhlaghpoor S, Fatehi M. Findings of bilateral coronary to pulmonary artery fistula in 64-multislice computed tomographic angiography: correlation with catheter angiography. J Comput Assist Tomogr 2008;32(2):271–3. [DOI] [PubMed]
- 4.Muzzi L, D'Angeli I, Pugliese G, Ricci M, Rose D, Chirichilli I, et al. Multi-slice computed tomography diagnosis of a coronary-pulmonary artery fistula. Eur J Radiol Extra 2009; 70(2):e61-e63.