Br Heart3' 1993;70:75-78

Angiographic diagnosis of anomalous coronary

artery in tetralogy of Fallot

Julene S Carvalho, Celia M C Silva, Michael L Rigby, Elliot A Shineboume

AbstractObjective-To obtain angiographic viewsin tetralogy of Fallot that can showwhether or not an anomalous coronaryartery passes anterior to the right ven-tricular outflow tract.Design-(a) A 10 year retrospectivereview of all patients who underwentrepair of tetralogy of Fallot up toDecember 1990; (b) a prospective studyof 30 children undergoing routine car-diac catheterisation.Patients and methods-295 cases inwhom standard angiographic views hadbeen used were reviewed retrospectively.Thirty non-consecutive children withtetralogy of Fallot were studied prospec-tively, including one child previouslystudied in whom diagnosis of an unsus-pected anomalous coronary artery wasmade only at operation. The aortogramwas performed with > 450 caudocranialand 20°-30° left anterior oblique angles.Setting-Tertiary referral centre.Results-Ten of the 295 cases reviewedwere shown to have a coronary vesseltraversing the right ventricular outflowtract. In one case the diagnosis was sus-pected before operation but it wasmissed in the others. Even in retrospectwe could not be certain of the preciseanatomy with the use of standard angio-graphic views. In the prospective studythe caudocranial aortogram showed theaortic valve face on in all the patients.The right ventricular outflow tract lay ina left and anterior (seen as superior)position in relation to the aortic root.Thus any vessel crossing the outflowtract could be identified. Identification ofthe aortic cusps allowed precise defini-tion of the origin of the coronary arter-ies. AUl but four had normal origin andcourse of the coronary arteries. Four hadpaired left anterior descending arteries(including the restudied patient), in allcases with a large vessel originating fromthe right coronary artery passing acrossthe right ventricular outflow tract.Conclusions-Important anomalies ofthe coronary arteries in tetralogy ofFallot may remain undiagnosed if stan-dard angiographic projections are used.Aortography with >45' caudocranial and20°-30° left anterior oblique angles allowsprecise definition of the anatomy andcertainty as to whether any major vesselcrosses the right ventricular outflow

tract. Interpretation, however, can onlybe correct if the projection is technicallyadequate with a view of the aortic valveface on. Furthermore, a normal bifurca-tion of the left main stem does notexclude a second left anterior descendingartery crossing the pulmonary outflowtract.

(Br HeartJ7 1993;70:75-78)

Tetralogy of Fallot is one of the conditionsfor which cardiac catheterisation is still per-formed before operation in most centres.This is because non-invasive techniques maynot always permit identification of abnormali-ties of pulmonary arteries or of coronaryartery anatomy. The sensitivity and specificityof angiography for diagnosing coronaryanomalies, however, remains uncertain.Surgical and postmortem series suggest thatimportant coronary anomalies occur in 2% to10% of patients.'-3 The most common anom-aly, the left anterior descending artery arisingfrom the right coronary artery and crossingthe right ventricular outflow tract, is impor-tant in young infants undergoing completerepair. It may influence surgical mortality andmorbidity and has implications regardingtechnique and age of repair. Though age initself may not represent an incremental riskfactor for surgery,45 preoperative diagnosis ofa vessel crossing the right ventricular outflowtract remains a contraindication for earlyrepair if the use of an extracardiac conduit isto be avoided.We have found it difficult to make the

diagnosis with certainty based on standardangiographic views and decided to review our10 year experience. The use of a caudocranialaortogram has been described previously inpatients with aortic valve disease.6 Morerecently its use in children with transpositionof the great arteries has been reported.7 Thisprompted us and others8 to assess its use intetralogy of Fallot. A prospective study wasthen carried out with this purpose.

Patients and methodsTo obtain retrospective data records ofpatients who underwent complete repair oftetralogy of Fallot at the Royal BromptonHospital from January 1980 to December1990 were reviewed.To obtain prospective data we studied 30

non-consecutive patients with tetralogy of

Department ofPaediatric Cardiology,Royal BromptonNational Heart andLung Hospital,LondonJ S CarvalhoM L RigbyE A ShineboumeDisciplina deCardiologia, EscolaPaulista de Medicina,Sao Paulo, BrazilC M C SilvaCorrespondence to:Dr E A Shinebourne,Department of PaediatricCardiology, RoyalBrompton National Heartand Lung Hospital, SydneyStreet, London SW3 6NP.Accepted for publication21 January 1993

75

on May 11, 2020 by guest. P

rotected by copyright.http://heart.bm

j.com/

Br H

eart J: first published as 10.1136/hrt.70.1.75 on 1 July 1993. Dow

nloaded from

Carvalho, Silva, Rigby, Shinebourne

Fallot undergoing routine cardiac catheterisa-tion. This included one child with an anom-alous left anterior descending coronary arterymissed at previous cardiac catheterisation butidentified at surgery.Twenty had a left and 10 a right sided aor-

tic arch. Age varied from one month to 11 8years (median 17 months). Either a retro-grade (n = 25) or anterograde approach (n =5) was used for the biplane aortogram, whichwas performed with a minimal 450 caudocra-nial and 20°-30° left anterior oblique angula-tion as well as a straight lateral projection. Infour of the cases studied by a retrogradeapproach aortography was performed with apigtail catheter but in general a standardNational Institute of Health catheter gavebetter opacification of the coronary arteries.When possible, however, an anterogradeapproach with a balloon tipped catheter withthe balloon inflated in the ascending aorta,was preferable.

ResultsRETROSPECTIVE STUDYRecords for 295 patients were reviewed. Ten(five males and five females) had an associat-ed anomalous coronary artery. Age at time ofrepair ranged from 10 months to 7-6 years.All had undergone preoperative echocar-diography and cardiac catheterisation.Aortography and left ventriculography hadbeen performed in one or two of the follow-ing views: anteroposterior, lateral, or leftanterior oblique for the aortogram and later-al, long axis, or right oblique for the left ven-triculogram. In only one case was there a highdegree of doubt that an abnormality of coro-nary artery anatomy was present. Six had hadprevious palliative surgery. One of these hadfirst stage correction (relief of the right ven-tricular outflow tract but no closure of theventricular septal defect) and an anomalousvessel was identified at surgery. Subsequently,but before definitive repair, angiography was

carried out with selective coronary arteryinjections. In this case, all six standard views,anteroposterior, lateral, right and left anterioroblique with and without craniocaudal tilt,were used but still there was no certainty asto the course of the vessel passing in front ofthe right ventricular outflow tract. In all casesit was necessary to modify the technique ofrepair as the usual incision to the right ven-tricular outflow tract could not be made. Acombination of modified right ventriculo-tomy, right atriotomy, and pulmonary arterio-tomy was used. Good relief of right sidedobstruction was achieved in all patients butfour required interposition of a conduitbetween the right ventricle and the pul-monary artery.

PROSPECTIVE STUDYSelective coronary arteriography (fig 1) in onecase and placement of a second catheter inthe right ventricular outflow tract (fig 2) inanother facilitated understanding and con-firmed how the anatomy is displayed in thecaudocranial angiographic projection with theleft oblique angle. In a third case the aortawas reached by an anterograde route with thevenous catheter and spillage of contrast intothe right ventricle and the right ventricularoutflow tract by accident contributed furtherto the understanding of the relation of thecoronary arteries to the right ventricular out-flow tract (fig 3). The course of the left ante-rior descending artery was seen by looking atthe interventricular septum with the sameangles during left ventriculography in twocases. Four patients (including the patientwith a known abnormality) were shown tohave a large left anterior descending arteryfrom the right coronary artery as well as asecond left descending artery from the leftcoronary cusp, so two vessels were supplyingthe area of the left anterior descending artery(figs 4 and 5). In the remaining 26 patientsthe coronary distribution was normal andnone had an abnormal branch across the area

l- 4Figure 1 Selective right (A) and left (B) coronary arty injections displayed in the caudocranial left anterior obliqueview in a patient with tetralogy ofFallot and normal distribution of coronary arteries. Note the course of the vessels as theyarisefrom the right (A) and left (B) coronary sinuses. Cx, circumflex artery; LAD, left anterior descending artery; LMS,left main stem; RCA, right coronary artery.

76

on May 11, 2020 by guest. P

rotected by copyright.http://heart.bm

j.com/

Br H

eart J: first published as 10.1136/hrt.70.1.75 on 1 July 1993. Dow

nloaded from

Angiographic diagnosis of anomalous coronary artery in tetralogy of Fallot

Figure 2 Retrograde arterial aortogram taken with a Figure 3 Anterograde venous aortogram from a patientsimultaneous venous catheter placed in the outflow tract of with tetralogy of Fallot. Note the normal relations of thethe right ventricle from a patient with tetralogy of Fallot. two coronary arteries to the right ventricular outflow tractNote the three cusps of the aortic valve and the two a, anterior; Cx, circumflex artery; 1, left; LAD, leftbranches of the left coronary artery. Cx, circumflex artery; anterior descending artery; p, posterior; r, right; RCA,LAD, left anterior descending artery; L, left coronary cusp; right coronary artery; RVOT, right ventricular outflowN, non-coronary cusp; R, right coronary cusp; RVOT, tract.right ventricular outflow tract; V, venous catheter.

of the right ventricular outflow tract. In threecases the conus branch, arising from the rightcoronary artery, was enlarged but did not runacross the outflow tract area. In 21 cases theanatomy was known or was confirmed at timeof surgery, including three of four with abnor-mality. In one, the vessel originating from theright coronary artery and supplying the leftdescending territory was considered smallerthan the artery coming from the left coronarysinus. Relief of the right ventricular outflowtract obstruction was through the pulmonaryartery and right atrium. Three patients haveundergone palliative procedures, includingone with abnormality. The rest await surgicaltreatment.The lateral aortogram performed simulta-

neously was unhelpful in assessing the coro-nary artery anatomy with certainty but was

Figure 4 Anterograde venous aortogram from a patientwith tetralogy ofFallot and anomalous coronary artery.Note that a large left anterior descending artery arisesanomalously from the right coronary artery and traversesthe area of the right ventricular outflow tract. A second,smaller descending artery is also seen. LAD, left anteriordescending artery; RCA, right coronary artery.

used to show the presence or absence of anarterial duct.

DiscussionSuccessful display of coronary artery anatomyin tetralogy of Fallot, reported by means of aventriculogram or flush aortogram910 or withselective coronary artery injections has beenreported.'" This has not been our experiencewith aortography and we do not carry outselective coronary arteriography routinely.Cross sectional echocardiography may also beused.'2 13 Although it is possible to identifyabnormal vessels across the right ventricularoutflow tract, there may not be an adequateview of the coronary anatomy in a significantproportion of patients. Berry et al correctlyand blindly distinguished normal and abnor-

Figure 5 Retrograde arterial aortogram from a patientwith tetralogy of Fallot. Note paired left anteriordescending arteries. One passes across the pulmonaryoutflow tract, the other arises normallyfrom the left mainstem. Cx, circumflex artery; RCA, right coronary artery;LAD, left anterior descending artery.

77

on May 11, 2020 by guest. P

rotected by copyright.http://heart.bm

j.com/

Br H

eart J: first published as 10.1136/hrt.70.1.75 on 1 July 1993. Dow

nloaded from

Carvalho, Silva, Rigby, Shinebourne

mal patterns in the coronary circulation ofsome patients with tetralogy of Fallot but itwas not possible to see the coronary arterieswell enough in over 20% of their patients. Inonly two cases was this due to large patientsize.'2To show a branch of a major coronary

artery passing anterior to the right ventricularoutflow tract in tetralogy of Fallot it is neces-sary to show the coronary arteries clearly andalso to know where the right ventricular out-flow tract lies in the projection chosen for theaortogram. Overlapping of the coronarybranches is the rule with most standardviews. This leads to confusion and failure torecognise abnormal patterns when interpret-ing the angiograms. In our retrospective seriesthe prevalence of surgically important anom-alies of the coronary artery was 3-4% but thediagnosis was not made with certainty in anyof the cases although suspected in one.Conversely, in our prospective series ofpatients in whom a caudocranial aortogramwas performed, the diagnosis was made withcertainty in four cases and, equally important,we could be certain that no major coronaryartery passed anterior to the right ventricularoutflow tract in the rest.With the use of a caudocranial angle for

the aortogram the aortic valve is seen face on.Its three cusps are clearly seen and the originand course of the coronary arteries are easilyfollowed by the absence of overlapping aspointed out by Mandel et al.7 Furthermore,and of crucial importance in patients with thiscondition, knowing that the position of theright ventricular outflow tract is to the leftand slightly anterior to the aortic valve allowsidentification of any abnormal branch cross-ing the area. To be certain, however, a cor-rect projection of the base of the heart isrequired (as if the observer were looking atthe heart from below and slightly from theleft). The aortic arch itself is foreshortenedand therefore the aortic valve must be seenface on or nearly so. This view is thusanalagous to the echocardiographic paraster-nal short axis section at the level of the aorticvalve. In both, the normal left mainstem canbe seen passing behind (beneath) the rightventricular outflow tract and dividing into leftanterior descending and circumflex arteries,but we have already emphasised the potentialdeficiency of echocardiography in the individ-ual patient.

The caudocranial aortogram, when per-formed correctly, allows distinction betweenright and left, posterior and anterior (but notinferior and superior) relations (fig 3). Thus itshould be possible to detect an abnormal ori-gin or course of a coronary artery and to'seeits anterior or posterior relation to the pul-monary outflow tract. Any major coronarybranch passing anterior to the right ventricu-lar outflow tract is likely to be of importanceto the surgeon, and management can then bedirected accordingly. It is also important tosee both coronary arteries as identification ofone normal left anterior descending arterydoes not exclude a paired artery originatingfrom the right coronary artery and crossingthe pulmonary outflow tract. Our currentpractice is to use 450 caudocranial and 300left anterior angulation in all patients. Wehave shown that by using this angiographicprojection it is possible to detect these abnor-malities before operation.

1 Berry BE, McGoon DC. Total correction for tetralogy ofFallot with anomalous coronary artery. Surgery 1973;74:894-7.

2 Meng CC, Eckner FA, Lev M. Coronary artery distribu-tion in tetralogy of Fallot. Arch Surg 1965;90:363-6.

3 Howe A, Rastelli GC, Ritter DG, Dushane JW, McGoonDC. Management of right ventricular outflow tract insevere tetralogy of Fallot. J Thorac Cardiovasc Surg1970;60:131-43.

4 Touati GD, Vouhe PR, Amodeo A, Pouard P, Mauriat P,Leca F, et al. Primary repair of tetralogy of Fallot ininfancy. J Thorac Cardiovasc Surg 1990;99:396-403.

5 DiDonato RM, Jonas RA, Lang P, Rome JJ, Mayer JE,Castaneda AR. Neonatal repair of tetralogy of Fallotwith and without pulmonary atresia. J Thorac CardiovascSurg 1991;101:126-37.

6 Stein PD, Sabbah HN. Orifice-view roentenography forevaluation of the aortic valve. American Journal ofRoentgenology Radium Therapy and Nuclear Medicine1975;125:847-53.

7 Mandell VS, Lock JE, Mayer JE, Parness IA, Kulik TJ.The 'Laid-back' aortogram: An improved angiographicview for demonstration of coronary arteries in transposi-tion of the great arteries. Am J Cardiol 1990;65:1379-83.

8 O'Sullivan In, Bain HH, Hunter S, Wren C. The 'end-on'aortogram in tetralogy of Fallot: Improved angiographicdefinition of coronary arteries without selective angio-graphy. Pediatr Cardiol 1992;13:247.

9 Fellows KE, Freed MD, Keane JF, Van Praagh R,Bernhard WF, Castaneda AC. Results of preoperativecoronary angiography in tetralogy of Fallot. Circulation1975;51:561-6.

10 Fellows KE, Smith J, Keane JF. Preoperative angiocardio-graphy in infants with tetrad of Fallot. Am J Cardiol1981;47: 1279-85.

11 Dabizzi RP, Caprioli G, Aiazzi L, Castelli C, Baldrighi G,Parenzan L, et al. Distribution and anomalies of coro-nary arteries in tetralogy of Fallot. Cirulation 1980;61:95-102.

12 Berry Jr JM, Einzig S, Krabill KA, Bass JL. Evaluation ofcoronary artery anatomy in patients with tetralogy ofFallot by two-dimensional echocardiography. Circulation1988;78: 149-56.

13 Jureidini SB, Appleton RS, Nouri S. Detection of coro-nary artery abnormalities in tetralogy of Fallot by two-dimensional echocardiography. J Am Coil Cardiol1989;14:960-7.

78

on May 11, 2020 by guest. P

rotected by copyright.http://heart.bm

j.com/

Br H

eart J: first published as 10.1136/hrt.70.1.75 on 1 July 1993. Dow

nloaded from