Ann Thorac Surg 1997;63:1152-1155
© 1997 The Society of Thoracic Surgeons
Case Report
Rastelli Procedure for Repair of Transposition of the Great Arteries {S, D, L} Complex
Giovanni Battista Luciani, MD,
Alessandro Mazzucco, MD
Division of Cardiac Surgery, University of Verona, Verona, Italy
Accepted for publication November 1, 1996.
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Abstract
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Transposition of the great arteries with {S, D, L} segmental anatomy is a rare complex congenital heart lesion. The morphologic features of this unusual disease make surgical repair more challenging than in {S, D, D} transposition. Here reported is the experience with the surgical treatment of this pathologic condition in 2 patients presenting with significant associated anomalies of the right side of the heart and pulmonary outflow tract. Relevance of the specific anatomic features of the transposition {S, D, L} complex is reviewed in terms of feasibility of biventricular repair using the Rastelli operation.
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Introduction
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Transposition of the great arteries (TGA) with {S, D, L} segmental set is a rare lesion in which the transposed aortic valve lies to the left of the transposed pulmonary valve with atrioventricular concordance and ventriculoarterial discordance. Due to the frequent association with anomalies of the right-heart and pulmonary outflow tract, surgical management of the TGA {S, D, L} complex using the arterial switch operation is often contraindicated. Biventricular repair using either the Rastelli operation or the REV procedure, or, in unfavorable cases, univentricular palliation may be necessary instead [1–3].
Here reported is our experience with the surgical treatment of the TGA {S, D, L} complex in 2 children with severe malformations of the right side of the heart and pulmonary outflow tract.
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Case Report
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Patient 1
A full-term 2.9-kg male presented cyanosis and cardiac murmur at birth. Echocardiographic examination showed TGA with levoposition of the aorta, ventricular septal defect (VSD), and pulmonary outflow tract obstruction. At age 3 months a right modified Blalock-Taussig shunt was performed using a 4-mm polytetrafluoroethylene prosthesis via a right thoracotomy (Table 1
). Cardiac catheterization at 20 months of age disclosed TGA {S, D, L}, a large conoventricular noncommitted VSD, and multiple small, midmuscular and apical VSDs, subpulmonary and pulmonary stenosis, and a patent right modified Blalock-Taussig shunt. Marked leftward and posterior malalignment of the conal septum (CS) and right ventricular (RV) hypoplasia were also noted (Table 2).
At age 2 years, the child underwent surgical repair using the Rastelli procedure. Via a right ventriculotomy the RV sinus was found markedly hypoplastic with thick trabeculation. The conoventricular VSD and multiple muscular defects gave to the trabecular septum the appearance of a rudimentary structure. To allow for intracardiac rerouting, the CS was resected up to the pulmonary valve anulus, converting the VSD into a doubly committed (subarterial) defect. Left ventricular outflow tract rerouting and ventricular septation were obtained using a large Dacron patch. The RV outflow was reconstructed using a 16-mm pulmonary homograft placed in a heterotopic position with a pericardial shield extension. The left pleural space was entered so that the conduit would entirely lie slightly to the left of the sternum. The postoperative recovery was prolonged due to persistence of congestive failure necessitating digitalis, furosemide, and captopril therapy.
Six months after repair, the child presented with an episode of pulmonary edema. Repeat catheterization identified multiple residual VSDs giving a cumulative pulmonary-to-systemic flow ratio of 2.5:1 warranting reoperation. Reentry of the median sternotomy was uneventful due to both the polytetrafluoroethylene patch protection and the leftward position of the homograft. By incision of the pericardial extension of the homograft, we repaired two anterior and two inferior VSDs primarily. Postoperative recovery was complicated by third-degree atrioventricular block, which required permanent pacing.
Follow-up examination of the child revealed a 13 kg, 3-year-old boy with adequately paced cardiac rhythm and controlled congestive failure. Echocardiography showed a markedly hypokinetic left ventricle despite absence of right and left ventricular outflow obstruction, and of intracardiac shunts.
Patient 2
A full-term 3.1-kg girl presenting with cyanosis at birth had echocardiographic diagnosis of TGA with levoposition of the aorta, VSD, and pulmonary outflow tract obstruction. A Waterston procedure was performed via a right thoracotomy when the patient was 2 months of age (see Table 1
). The child maintained a satisfactory growth pattern, and complete repair was performed at age 6 years. After take-down of the Waterston anastomosis, a large subaortic conoventricular VSD was found via a right ventriculotomy. The RV sinus was hypoplastic with prominent muscular trabeculation and malalignment of the CS with subpulmonary stenosis (see Table 2). A wedge of CS muscle was resected, and the left ventricular outflow was rerouted under the aortic valve using a large Dacron patch. The RV outflow tract was reconstructed using a 16-mm composite graft (porcine xenograft), and the right branch pulmonary artery was reconstructed using a pericardial patch.
Postoperative recovery and subsequent follow-up proved uncomplicated until the age of 14 years, when the patient was admitted for worsening exertional dyspnea. Echocardiographic examination showed a critically stenotic (peak pressure gradient 80 mm Hg) porcine bioprosthesis. Via repeat sternotomy, under normothermic bypass the composite graft was replaced with a size 20 pulmonary homograft. The postoperative course was complicated by hemorrhage due to tear of the right pulmonary artery, requiring reexploration and patch arterioplasty. Early postoperative echocardiography showed a small residual VSD and mild RV outflow obstruction (20 mm Hg).
The patient's subsequent clinical status proved satisfactory for nearly 7 years, when increasing exertional dyspnea warranted reassessment. Catheterization disclosed a severely hypoplastic RV with thick trabeculations of the sinus and infundibular portions, reminiscent of double-chamber RV (Fig 1), stenotic conduit, long-segment hypoplasia of the right pulmonary artery, and residual ventricular level left-right shunt. Manometry demonstrated multiple intraventricular pressure gradients adding up to a peak gradient of 100 mm Hg and normal pulmonary artery pressure. Through a fourth median sternotomy, the homograft conduit was found to be compressed by the inner sternal table. Inspection of the RV chamber confirmed hypoplasia of the sinus. A partial dehiscence of the VSD patch under the tricuspid annulus was repaired using a Dacron patch. The RV outflow was reconstructed with a size 24 pulmonary homograft, placed in a heterotopic position using a Dacron patch extension. The conduit was allowed to fall leftward of the sternum, and a polytetrafluoroethylene patch was placed between the graft and the sternal table. In spite of moderately elevated RV filling pressures (central venous pressure = 14 mm Hg), recovery was regular and the patient was discharged on the 7th postoperative day.
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Fig 1. . Right anterior oblique projection of the right ventricular angiogram in patient 2 showing a hypoplastic sinus portion with multiple thick, muscular trabeculae extending to the conus. Obstructions at the right ventricular cavitary, subpulmonary valvar, and pulmonary valvar levels are evident.
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Comment
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Transposition of the great arteries with {S, D, L} segmental set presents the same segmental alignments, atrioventricular concordance, and ventriculoarterial discordance of TGA {S, D, D}. However, the transposed aortic valve lies to the left of the transposed pulmonary valve [1]. In spite of its rare occurrence, recent clinicopathologic evidence has found a high prevalence of specific associated anomalies, thereby identifying a malformation complex [1]. Six interrelated morphologic features have been more frequently recognized in TGA {S, D. L}, including (1) conoventricular VSD, (2) CS leftward and posterior malalignment, (3) RV hypoplasia, (4) pulmonary outflow tract obstruction, (5) ventricular malposition, and (6) absent left coronary ostium. The unifying interpretation explaining these associations suggests that TGA {S, D, L} is not only a malformation of the conus, but also of the ventricular segment [1].
In agreement with the comprehensive review by Houyel and associates [1], the 2 cases here presented confirm the involvement of both the conal and the ventricular segment of the heart. Both our patients presented with a conoventricular VSD, noncommitted in 1 and subaortic in the other. In 1 patient, however, multiple midmuscular and apical defects gave the trabecular septum a rudimentary aspect, similar to that found in single ventricle. The CS was well developed and displaced leftward and posteriorly in both. One child presented with bilateral conus. Thus both presented with pulmonary outflow tract stenosis, worsened by valve stenosis in 1. More importantly, the degree of RV underdevelopment was remarkable in the 2 patients, in 1 associated with intracavitary obstruction.
Reports of successful Rastelli or REV operations for TGA {S, D, L} with subpulmonary stenosis have thus far been sporadic [1, 4]. Due to scarring of and around the branch pulmonary arteries, the feasibility of a REV procedure appeared questionable in our 2 patients. Consequently, a Rastelli operation was performed in both cases. As both children presented with significant pulmonary outflow tract obstruction and CS hypertrophy, resection of the conal muscle was mandatory to obtain adequate intracardiac rerouting. However, coexistence of RV anomalies and the anatomy of the ventricular septum resulted in important postoperative sequelae.
In the first child, the presence of a very rudimentary septum predisposed toward persistence of interventricular communications needing reoperation. The combination of a second ischemic insult to the myocardium and of atrioventricular block necessitating sequential pacing resulted in persistent left ventricular dysfunction, affecting the long-term outlook of the child. The patient is currently being considered for heart transplantation.
In the second patient, the very same anatomy of the RV sinus, with the tendency of the trabeculations to hypertrophy over time, associated with the unavoidable compression of the anteriorly positioned conduit by the sternum determined the need to reintervene for a fourth time. Despite relief of intracavitary and outflow obstruction, the small volume of the RV cavity casts some serious doubts in terms of long-term systolic and diastolic function of the ventricle.
In our limited experience with 2 cases of the TGA {S, D, L} complex, the Rastelli procedure was technically feasible, but not free from complications. The fact that median sternotomy reentries proved safe in our patients, possibly due to clever positioning of the conduit to the left of the sternum, should not lead one to underestimate the devastating impact of multiple surgical procedures. It may be contended that due to the number of interventions (three in 1 patient and five in the other) during a limited span of time (3 to 14 years) and, more importantly, considering the anatomic features of the right heart and ventricular septum, a univentricular approach to TGA {S, D, L} with subpulmonary stenosis may have been as well justified in our patients, even in the presence of two patent atrioventricular valves and two ventricles.
In conclusion, a Rastelli repair in children with the TGA {S, D, L} complex is feasible. Due to the sometimes severe degree of the associated anomalies of the RV and ventricular septum, in addition to the intrinsic need for reintervention that a homograft conduit carries, univentricular palliation may be considered an acceptable alternative in selected cases.
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Footnotes
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Address reprint requests to Dr Luciani, Division of Cardiac Surgery, University of Verona, O. C. M. Piazzale Stefani 1, Verona, 31726, Italy.
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References
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- Houyel L, Van Praagh R, Lacour-Gayet F, et al. Transposition of the great arteries {S, D, L}. Pathologic anatomy, diagnosis, and surgical anatomy of a newly recognized complex. J Thorac Cardiovasc Surg 1995;110:613–24.[Abstract/Free Full Text]
- Lecompte Y, Neveux JY, Leca F, et al. Reconstruction of the pulmonary outflow tract without prosthetic conduit. J Thorac Cardiovasc Surg 1982;84:727–33.[Abstract]
- Vouhé PR, Tamisier D, Leca F, Ouaknine R, Vernant F, Neveux JY. Transposition of the great arteries, ventricular septal defect, and pulmonary outflow tract obstruction: Rastelli or Lecompte procedure? J Thorac Cardiovasc Surg 1992;103:428–36.[Abstract]
- Matsuda H, Woong Kang J, Kido T, et al. Successful Rastelli operation in infant with complete transposition of great arteries, levoposition of aorta, and subaortic ventricular septal defect. Ann Thorac Surg 1982;34:590–3.[Abstract]
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Abstract
Introduction
