A Method of Outflow Tract Reconstruction in Tetralogy of Fallot with Anomalous Anterior Descending Coronary Artery Lawrence I. Bonchek, M.D. ABSTRACT An anomalous anterior descending

coronary artery that arises from the right coronary and crosses the right ventricular outflow tract can compromise corrective operations for tetralogy of Fallot. The only safe method of outflow tract reconstruction reported until now is the use of a tubular graft from the right ventricle to the pulmonary artery. We report successful reconstruction of the outflow tract by placing a standard fabric patch under the mobilized anomalous coronary artery. This technique should avoid the late complications of tubular conduits by preserving the natural posterior wall of the outflow tract for growth.

Coronary artery anomalies occur in 2 to 9% of patients with tetralogy of Fallot [ 2 ] . In the anomaly that is most important surgically, the anterior descending coronary artery (AD) arises from the right coronary artery and crosses the right ventricular (RV) outflow tract [5]. Intraoperative injury to this artery is often fatal [4], and the right ventriculotomy must therefore be planned to preserve the AD intact. Although a transverse ventriculotomy can often be used to expose the ventricular septa1 defect, this approach does not allow correction of a hypoplastic pulmonary annulus unless the anomalous AD crosses the RV infundibulum some distance proximal to the annulus so that an outflow tract patch can be inserted distal to the anomalous AD. In the past, some patients with tetralogy, a hypoplastic pulmonary annulus, and an anomalous AD had incomplete relief of outflow tract obstruction or were treated with palliative operations since completely corrective operaFrom the Division of Cardiopulmonary Surgery, University of Oregon Health Sciences Center, 3181 SW Sam Jackson Park Rd, Portland, OR. Accepted for publication Sept 9, 1975. Address reprint requests to Dr. Bonchek, Department of Thoracic and Cardiovascular Surgery, Medical College of Wisconsin, 8700 W Wisconsin Ave, Milwaukee, WI 53226.

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tions often were not feasible. More recently, a few patients have undergone successful correction by the insertion of tube conduits between the right ventricle and pulmonary artery [l,61. We have corrected this complex of anomalies in 1 child without a tube graft and report here the technique used. Case Report The patient was an 11-year-old girl who weighed only 24 kg and measured 125 cm. She had undergone a left Blalock-Taussig shunt at the age of 5 years because of cyanosis and polycythemia. Subsequent catheterization at another hospital revealed a functioning shunt and typical findings of tetralogy with a hypoplastic pulmonary annulus, systemic RV pressure, and main pulmonary artery pressure of 30110 mm Hg. The coronary artery anatomy was not evaluated. An elective operation was recommended because of marked growth retardation and exercise intolerance. Operation was performed at the University of Oregon Medical School Hospital on August 7, 1973. Inspection of the heart revealed a large AD crossing the RV outflow tract at the level of the pulmonary annulus (Figure, A). The BlalockTaussig shunt was ligated as high-flow cardiopulmonary bypass was instituted. A vertical ventriculotomy was then made, and the pulmonary annulus was assessed from below; it would not accept a 4 mm dilator. (The pulmonary artery was of reasonable size; the hypoplasia of the annulus may have been due in some measure to the functioning Blalock shunt.) It was clear that adequate relief of the obstruction would require a patch across the annulus. Accordingly, the coronary artery was carefully dissected free and a 3 cm length was mobilized so that it could be lifted off the outflow tract (Figure, B); there were no branches from this segment of the artery. With this safely accomplished, the ventricular

452 The Annals of Thoracic Surgery Vol 21 No 5 May 1976

( A )Frontal view of the heart. T h e anomalous coronary artery crosses the R V o u t f l o w tract at the level of the annulus (dotted lines). (B)T h e artery has been dissected free f r o m the ventricle and the

ventriculotomy carried under the elevated vessel. (C) After closure of the septa1 defect, the outflow tract is widened w i t h a Teflon patch. (D)T h e completed repair.

453 How to Do It: Bonchek: Tetralogy of Fallot with Anomalous ADCA

septa1 defect was closed with a patch during a techniques when feasible. Although postoperasingle period of aortic cross-clamping. The ven- tive catheterization has not yet been carried out triculotomy was then extended across the an- in our patient, her clinical course assures an nulus underneath the coronary artery, and an uncompromised coronary artery. Satisfactory reelliptical patch of woven Teflon measuring 1.5 lief of RV obstruction was documented incm at its greatest diameter was used to widen the traoperatively, and late hemodynamic deterioraoutflow tract. The mobilized coronary artery tion is not to be expected after such an adequate segment was quite elastic and bridged this extra immediate result [7]. Finally, the method we distance without apparent tension (Figure, C, employed need not cause concern about delayed D). A patent foramen ovale was then closed stretching of the coronary artery since the size of through a small atriotomy. the outflow tract is fixed anteriorly by the synAfter cardiopulmonary bypass was discon- thetic patch; growth will occur posteriorly. tinued, the RV systolic pressure was 45 mm Hg, This technique will not prove necessary or pulmonary arterial systolic pressure was 20 mm even applicable in every patient with tetralogy, a Hg, and aortic systolic pressure was 100 mm Hg. hypoplastic pulmonary annulus, and an The postoperative course was uneventful. anomalous LAD since AD coronary arteries that Two years later the patient was asymptomatic cross the right ventricle below the level of the and taking no medications. A chest roentgeno- annulus could have large branches to the muscle gram showed mild cardiomegaly, and right that would complicate the dissection we carried bundle-branch block was evident on the elec- out. The success of this technique in our patient trocardiogram. Postoperative catheterization is suggests, however, that it should be considered planned electively at the next annual check-up. for patients with tetralogy and anomalous coronary arteries before tube grafts are routinely inComment serted. The combination of tetralogy of Fallot, severe hypoplasia of the pulmonary annulus, and anomalous AD has not previously been consid- References ered correctable with standard techniques that 1. Berry BE, McGoon DC: Total correction for tetralinvolve an incision through the area of outflow ogy of Fallot with anomalous coronary artery. Surgery 74:894, 1973 tract narrowing. Recently, as a result of success with tubular conduits to reconstruct the RV out- 2. Fellows KE, Freed MD, Keane JF, et al: Results of routine preoperative coronary angiography in tetflow tract in various other congenital anomalies, ralogy of Fallot. Circulation 51:561, 1975 these grafts have been applied to patients with 3. Kirklin JW, Karp RB: The Tetralogy of Fallot from a tetralogy and anomalous coronary arteries [l, 61. Surgical Viewpoint. Philadelphia, Saunders, 1970 This approach is technically straightforward, 4. Longnecker CG, Reemstma K, Creech 0 Jr: Anomalous coronary artery distribution associated but late complications may occur with such with tetralogy of Fallot: hazard in open cardiac grafts. Anastomotic strictures occasionally rerepair. J Thorac Cardiovasc Surg 42:258, 1961 quire revision postoperatively; small grafts in- 5. Meng LCC, Eckner FAO, Lev M: Coronary artery serted in young children may prove inadequate distribution in tetralogy of Fallot. Arch Surg later; and the fate of prosthetic or tissue valves 90:363, 1965 that are often included in the grafts remains un- 6. Meyer J, Chiariello L, Hallman GL, et al: Coronary artery anomalies in patients with tetralogy of Falcertain. lot. J Thorac Cardiovasc Sslrg 69:373, 1975 The long-term results of correction of tetralogy 7. Sunderland CO, Matarozzo RG, Lees MH, et al: with standard methods have been well Total correction of tetralogy of Fallot in infancy: documented and are satisfying 13, 71; we have postoperative hemodynamic evaluation. Circulatherefore considered it wise to adhere to proved tion 48:398, 1973

A method of outflow tract reconstruction in tetralogy of Fallot with anomalous anterior descending coronary artery.

An anomalous anterior descending coronary artery that arises from the right coronary and crosses the right ventricle outflow tract can compromise corr...
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