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Coronary artery fistulas are a rare disorder,accounting for approximately 0.2% to 0.4% of con-genital cardiac defects.1 They can present anytimefrom infancy through adulthood with signs rangingfrom a cardiac murmur to congestive heart failure tomyocardial ischemia or infarction.2 Diagnosis can bemade by both transthoracic and transesophagealechocardiography and by cardiac catheterization.There has been 1 report of a prenatal diagnosis of aright coronary to right ventricle fistula.3 These fistu-las are usually closed either surgically or in thecatheterization laboratory. Rarely do they sponta-neously regress. This report presents the first case ofa prenatal diagnosis of a left coronary to right ven-tricular fistula in an otherwise structurally normalheart and follows its course to spontaneous closureby 1 year of age.

CASE REPORT

A 23-year-old woman was referred for fetal echocardiogra-phy at 30 weeks because of an abnormal screening ultra-sonography at 28 weeks that revealed a mildly dilated rightventricle.On the fetal echocardiogram, the heart had a nor-mal axis with normal cardiac segment connections. Right

atrial and right ventricular enlargement was seen with nor-mal biventricular function. Mild tricuspid regurgitationwas noted without any evidence of right ventricular out-flow tract obstruction. Both great vessels were of normalsize and orientation, and normal flow velocities werenoted. A shunt was noted from the interventricular sep-tum into the right ventricle by color flow Doppler evalua-tion (Figure 1).This shunt was determined to be diastolicby the timing of right ventricular inflow and outflow. Adiagnosis of a left anterior descending coronary artery tothe right ventricle fistula was made.

The patient was delivered by caesarian section at 34weeks because of prolonged rupture of membranes. Thebirth weight was 1760 g. The postnatal echocardiogramconfirmed the prenatal diagnosis.There was a dilated leftanterior descending coronary with prominent diastolicflow into the right ventricle (Figure 2). The patient did notshow any signs of congestive heart failure and so was treat-ed conservatively with observation. After discharge thepatient was lost to follow-up until 1 year of age. At thatvisit at 1 year no cardiac murmur was appreciated, andrepeat echocardiography revealed no evidence of patencyof the fistula (Figure 3).

DISCUSSION

Coronary artery fistulas are rare, comprising approx-imately 0.2% to 0.4% of all congenital cardiac defectswith an equal distribution between male and femalepatients.1 Between 55% to 60% arise from the rightcoronary artery, and they most commonly drain intothe right ventricle and less frequently into the rightatrium or pulmonary artery.4 The fistula may beeither small or dilated and tortuous and is usually an

Diagnosis of a Left Coronary Artery toRight Ventricular Fistula with

Progression to Spontaneous Closure

John Lawrence Cotton, MD, Chapel Hill, North Carolina

From the Division of Pediatric Cardiology, University of NorthCarolina at Chapel Hill.Reprint requests: John L. Cotton, MD, Division of PediatricCardiology, 311 Burnett-Womack, CB# 7220, Chapel Hill, NC27599-7220.Copyright © 2000 by the American Society of Echocardiography.0894-7317/2000 $12.00 + 0 27/4/102213doi:10.1067/mje.2000.102213

Coronary artery fistulas in structurally normalhearts are rare. The natural history of these lesionsdepends on their size and can cause congestiveheart failure, infective endocarditis, ischemia, oraccelerated atherosclerosis. These fistulas areusually closed either in the catheterization labora-tory or surgically. This case demonstrates the pre-

natal diagnosis of a left coronary to right ventricularfistula and documents its natural history to sponta-neous closure by 1 year of age. This may helpconfirm the rationale of observation rather thanclosure of small fistulas in selected cases of patientswithout symptoms. (J Am Soc Echocardiogr 2000;13:225-8.)

CASE REPORTS

isolated lesion, except in the case of pulmonary atre-sia with an intact ventricular septum, in which fistu-las are often seen.

Large fistulas can have a significant left to rightshunt and cause congestive heart failure. In addition,with a large fistula, the distal coronary circulation

Journal of the American Society of Echocardiography226 Cotton March 2000

may be at risk for coronary steal and myocardialischemia.5 Smaller fistulas may impose minimal or nohemodynamic burden. The natural history of theselesions partly depends on their size.Very small fistu-las may not increase in size, and there have been afew reports of spontaneous closure.6-9 Over the long

Figure 1 Horizontal apical 4-chamber view of a 30-week gestation fetus. Color flow in the interven-tricular septum (arrow) shows diastolic shunting into the right ventricle. RV, right ventricle; LV, left ven-tricle.

Figure 2 Postnatal apical 4-chamber view demonstrating length of fistula from the left anterior descend-ing coronary artery draining into the right ventricle. RA, right atrium; LA, left atrium; RV, right ven-tricle; LV, left ventricle.

Journal of the American Society of EchocardiographyVolume 13 Number 3 Cotton 227

term a patent fistula places the patient at risk for infec-tive endocarditis, congestive heart failure, ischemia,accelerated atherosclerosis, or rarely, rupture.2,6,9

Two-dimensional echocardiography can be usedto make the diagnosis.4,10 Visualization of an en-larged coronary vessel lumen with a tortuous coursecan be a sign. Pulse Doppler scanning within a coro-nary artery can show a continuous turbulent flow,and color flow Doppler mapping can identify theterminal connection into a cardiac chamber or ves-sel.These techniques are more sensitive with largerfistulas, and it is not uncommon that smaller fistulasgo undetected. Other imaging modalities such asmagnetic resonance imaging, computed tomogra-phy, and radionucleotide cine-angiography havebeen reported to aid in the diagnosis.11,12 Coronaryangiography can directly visualize a fistulous con-nection.13

Large coronary artery fistulas usually require sur-gical closure. More recently, smaller connectionshave been successfully closed with percutaneouscoil embolization.14 There have been several reportsof small fistulas closing spontaneously, so observa-tion in this scenario may be warranted in the pedi-atric age group.6-9

This case report demonstrates the natural historyof a coronary artery fistula.The initial diagnosis of aleft coronary to right ventricular fistula was madebefore birth, with subsequent postnatal follow-upleading to resolution by spontaneous closure. This

may help confirm the rationale of observation ofsmall fistulas in selected cases of patients withoutsymptoms.

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8. Hackett D, Hallidie-Smith KA. Spontaneous closure of coro-nary artery fistula. Br Heart J 1984;52:477-9.

Figure 3 Apical 4-chamber view at 1 year of age. No flow through the fistula (arrows) could be docu-mented by color flow scanning. RV, right ventricle; LV, left ventricle.

9. Davis JT, Allen HD, Wheller JJ, Chan DP, Cohen DM, TeskeDW, et al. Coronary artery fistula in the pediatric age group:A 19-year institutional experience. Ann Thorac Surg 1994;58:760-3.

10. Kimball TR, Daniels SR, Meyer RA, Knilans TK, Plowden JS,Schwartz DC. Color flow mapping in the diagnosis of coro-nary artery fistula in the neonate: benefits and limitations.Am Heart J 1989;117:968-71.

11. Wells RG, Litwin SB, Sty JR. Radionuclide cardioangio-graphic demonstration of a coronary artery fistula. PediatrRadiol 1986;16:61-4.

Journal of the American Society of Echocardiography228 Cotton March 2000

12. Boxer RA, LaCorte MA, Singh S, Ishmael R, Cooper R, SteinH. Noninvasive diagnosis of congenital left coronary arteryto right ventricle fistula by nuclear magnetic resonance imag-ing. Pediatr Cardiol 1989;10:45-7.

13. Hofbeck M, Wild F, Singer H. Improved visualization of acoronary artery fistula by the “laid-back” aortogram. BrHeart J 1993;70:272-3.

14. Mavroudis C, Backer CL, Rocchini AP, Muster AJ, Gevitz M.Coronary artery fistulas in infants and children: a surgicalreview and discussion of coil embolization. Ann Thorac Surg1997;63:1235-42.