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Conduit repairs of transposition complexes
Conduit repairs of transposition complexes A report of 14 cases Of 14 patients with transposition complexes undergoing conduit repairs, 10 had complete transposition of the great arteries (TGA) and 4 had double-outlet right ventricle. All 14 had ventricular septal defect (VSD). Ten had pulmonary stenosis, one had an atrial septal defect, and one had patent ductus arteriosus. The ages of the patients ranged from 13 months to 18 years. Six patients were treated with nine palliative operations: four systemic-pulmonary artery shunts, three atrioseptectomies, and two pulmonary banding procedures. Four patients died immediately after the operation. Among the 10 operative survivors, there were no late deaths during the follow-up periods from 5 months through 6 years. Review of the factors influencing the early operative results has stressed the importance of correct timing of operation with or without palliative treatment, increased surgical experience, and the critical evaluation of intracardiac anatomy.
Eisaburo Imamura, M . D . , * Tetsuo Morikawa, M.D., Katsuhiko Tatsuno, M.D., Kenji Okamoto, M.D.,** Yasuharu Imai, M . D . , and Souji Konno, M . D . , t Tokyo, Japan
V arious surgical approaches are available for correction of the transposition anomaly. The choice of an appropriate procedure depends primarily on the associated lesions. The principle of repair presented by Rastelli and colleagues 1 in 1969 has allowed for the correction of complex transposition anomalies. 2 - 4 The Rastelli procedure redirects both ventricular outflows by closing the ventricular septal defect (VSD) so as to separate the aortic orifice from the right ventricle and by using an external valved conduit to restore normal continuity between the right ventricle and the pulmonary artery. Thus an " a n a t o m i c " correction is achieved. At the Heart Institute of Japan and Tokyo Women's Medical College from January, 1970, through December, 1975, we have used this technique on 14 patients to correct transposition complexes. Ten patients had From the Department of Cardiovascular Surgery, Tokyo Women's Medical College and the Heart Institute of Japan, Tokyo, Japan. Received for publication July 12, 1976. Accepted for publication Dec. 13, 1976. Address for reprints: Dr. K. Tatsuno, Tokyo Women's Medical College, Shinjukuku, Tokyo 162, Japan. ♦Present address: Mayo Graduate School of Medicine, Rochester, Minn. 55901. **Present address: Tsukuba University School of Medicine, Ibargi, Japan. tDr. Konno died May 25, 1976.
570
complete transposition of the great arteries, and 4 had double-outlet right ventricles; all had associated VSD's. Ten of the 14 also had pulmonary stenosis. Materials and methods The present series comprises four groups (Table I): Group I, 8 patients who had complete (dextro-) transposition of the great arteries (d-TGA) with VSD and pulmonary stenosis; Group II, 2 patients who had d-TGA with VSD; Group III, 2 patients who had double-outlet right ventricle with subaortic VSD and pulmonary stenosis; and Group IV, 2 patients who had double-outlet right ventricle with subpulmonary VSD (Taussig-Bing malformation). The 14 patients shared a common anatomic feature—the aorta arose from the right ventricle, situated anterior to or along side the pulmonary artery. Patients with inverted ventricle or single ventricle were excluded from the series. Accordingly, the closure of the VSD was consistent in nature and is schematically illustrated in Fig. 1. The series included 7 boys and 7 girls whose ages ranged from 13 months to 18 years, with a mean age of 8 years. The body weights ranged from 8 to 53 kilograms and averaged 21 kilograms. All patients were symptomatically severely ill with cyanosis; the average preoperative hematocrit value was 60 per cent. Six patients had been treated with a total of nine palliative operations 7 to 9 years before total correction: four
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systemic-pulmonary artery anastomoses, three atrioseptectomies, and two pulmonary arterial banding procedures. The heart was exposed through a midline incision. Patients were placed on cardiopulmonary bypass with moderate hypothermia between 28 and 30° C. An elliptic opening was made on the anterior wall of the right ventricle. The VSD was enlarged (if it was not large enough) and was closed with the use of a Teflon patch so that blood from the left ventricle could electively be ejected into the ascending aorta. Because a largerthan-normal aorta is usual in the heart in which a VSD and pulmonary stenosis coexist, a defect size that was about 80 per cent or more of the individual aortic orifice was considered to be large enough. An aortic homograft, including the aortic valve, was used for reconstruction of the right ventricular outflow tract of the first patient.5 A xenograft pulmonary valve incorporated into woven Dacron tubes was employed in the subsequent 13 patients. The latter type of graft has an angled structure that resembles the natural outflow tract of the right ventricle. Its fabrication and clinical application have been discussed previously.6, 7 Group I: d-TGA with VSD and pulmonary stenosis. Six of the 8 patients with this anomaly underwent one-stage correction. The remaining 2 children were treated palliatively, one with a subclavianpulmonary artery anastomosis (Blalock-Taussig shunt) and the other with an atrioseptectomy. The latter procedure was done with the use of extracorporeal circulation. In 7 patients at operation, a VSD was found lying immediately beneath the aortic orifice. Of these 7, 2 required anterior enlargement of the VSD. In one patient (Case 4), two separate VSD's were located inferior to the crista supraventricularis, with the posterior defect being partially overhung by the tricuspid valve. To simplify the technique, the papillary muscle with chordae tendineae adherent to a well-developed muscular column that separated the defects was temporarily detached while the VSD's were being closed en bloc. Afterward, the divided end of the papillary muscle was reattached onto the wall of the Teflon internal conduit. All but one patient had combined valvular and subvalvular pulmonary stenosis. Two of the 8 patients had deformity of the left pulmonary artery (one with absent artery and one with hypoplasia). The other 6 patients had valvular stenosis only. Group II: d-TGA with VSD. Two children, ages 7 and 9 years, had undergone palliation with pulmonary banding and atrioseptectomy (Blalock-Hanlon procedure) at 3 months and 2 months of age, respectively. In both, the VSD was of infracristal type, requiring an-
Conduit repairs of transposition complexes
57 1
terosuperior enlargement. An interventricular tunnel was created without difficulty. The pulmonary valve and subvalvular tract were normally developed, with the pulmonary trunk distal to the banding being markedly dilated. In one child, the pulmonary trunk was transsected at the debanded site, the proximal end of which was oversewn. An external valved conduit was anastomosed to the distal end of the pulmonary artery in end-to-end fashion. In the other patient, the pulmonary trunk was tied at its root, and a longitudinal incision, 2.5 cm. long, was made distal to the ligature. The external conduit was anastomosed in end-to-side fashion. Group III: Double-outlet right ventricle with subaortic VSD and pulmonary stenosis. Two patients, ages 11 and 9 years, had undergone palliation with a Blalock-Taussig shunt at the age of 4 years and 13 months, respectively. A Waterston shunt was added in the latter patient 3 years later. In one child, surgical intervention initially was attempted to relieve the pulmonary stenosis by valvotomy and infundibulectomy. However, because a high gradient persisted, bypass was reinstituted and a conduit was inserted. Group IV: Double-outlet right ventricle with subpulmonary VSD. Two children, both 6 years of age, were seen initially because of frequent episodes of respiratory distress. The diagnosis was established at open-heart surgery. One child underwent emergency operation. A large VSD was located immediately beneath the pulmonary valve. Because the lower half of the VSD was overhung by the tricuspid valve, creation of the interventricular tunnel necessitated detachment of the chordae tendineae. The main pulmonary artery was ligated at its root, and an external conduit was inserted. The other patient was in a relatively stable state, enough so as to permit thorough diagnostic measures to be taken. Postoperative catheterization revealed pulmonary hypertension (90/50 mm. Hg) with a left-to-right shunt of 80 per cent and a pulmonarysystemic resistance ratio of 0.3. The pulmonary trunk was disconnected from the right ventricle by sewing each commissure of the pulmonary valve. After closure of the VSD, the continuity between the right ventricle and the pulmonary artery was re-established with an external valved conduit. The persistent ductus arteriosus was closed with a suture from within the pulmonary artery. Results Survival. Of the 14 patients, 4 died within 8 days after the operation. The operative mortality rate was 29 per cent. There have been no late deaths among the 10
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Table I. Patients with transposition complexes undergoing Rastelli repair
Case
Sex and age (yr.)
Weight (kg.)
Preop. hematocrit
(%)
Previous palliation
Date of operation
VSD
Pulmonary stenosis
1
M, 12
26
64
2
M, 7
16
72
Group I: d-TGA * with VSD and pulmonary stenosis 1/19/70 Supracristal Blalock-Taussig (5 yr.) 5/24/72 None Supracristal
3
M, 3
13
72
None
6/5/72
Supracristal
4
F, 4
13
74
None
7/3/72
Multiple, complicated
5
F, 1
8
45
None
6/19/73
6
M, 7
18
69
None
9/12/73
Supracristal, "enlarged" Supracristal
7
F, 8
20
66
None
10/11/73
8
F, 18
53
56
Open atrioseptectomy (11 yr.)
11/5/73
9
M,7
20
70
10
M, 9
21
58
11
M, 11
25
12
M, 9
20
13
F, 6
12
55
Group IV: Double-outlet right ventricle with VSD None 4/17/74 Subpulmonary
—
14
M, 6
16
44
None
-
Supracristal, "enlarged" Supracristal
Valvular and subvalvular Valvular and subvalvular hypoplasia of left pulmonary artery Valvular and subvalvular Valvular and subvalvular absence of left pulmonary artery Valvular Valvular and subvalvular Valvular and subvalvular Valvular and subvalvular
Group II: d-TGA with VSD Infracristal, 7/5/74 Closed artrioseptectomy and pul"enlarged" monary artery banding Infracristal, 2/12/75 Closed atrioseptectomy and pul"enlarged" monary artery banding
Subpulmonary
Good (6 yr.) Excellent (4 yr.)
Died, arrhythmias Died, low cardiac output
Died, low cardiac output Excellent (3 yr.) Excellent (2'/2 yr.) Excellent (2 yr., 5 mo.) Excellent (1 yr., 9 mo.)
Excellent (1 yr., 2 mo.)
Group Ih : Double-outlet right ventricle with VSD and pulmonary stenosis 9/13/72 Blalock-Taussig Subaortic Valvular and 48 (4 yr.) subvalvular 42 Blalock-Taussig 12/6/74 Subaortic Valvular and (13 mo.) subvalvular Waterston (4 yr.)
10/22/75
Results (follow-up)
Excellent (3 yr., 9 mo.) Excellent (1 yr., 5 mo.)
Died, low cardiac output Good (5 mo.)
*d-TGA, Complete transposition of great arteries. VSD, Ventricular septal defect.
patients who survived the operation during follow-up periods that ranged from 5 months to 6 years. Age and weight. Of the 10 operative survivors, 9 were 5 years old or older, with the oldest being 18 years. In contrast, 3 children less than 4 years of age died. The body weight reflected this tendency: The 10 survivors weighed between 16 and 53 kilograms,
whereas the 4 patients who died weighed between 8 and 13 kilograms. Palliative operation. Of the 8 patients in whom the primary surgical intervention was conduit repair, 4 died. All 6 patients who had had effective palliation underwent successful operation. The palliative procedures did not cause recognizable hazards at open-heart
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Conduit repairs of transposition complexes
Normally Related Great Vessels
573
Transposed Great Vessels
Fig. 1. Diagrams illustrating the Rastelli conduit repair. Arrows indicate direction of blood flow after repair. Dotted areas delineaterightventricular cavity. Note that while both ventricular compartments remain unchanged after the ventricular septal defect is closed in the heart with normally related great vessels (A), the effective right ventricular cavity is reduced by creation of an interventricular tunnel in heart with transposition (B). surgery. Of the 4 patients who were born without pulmonary stenosis, 3 survived total correction; 2 of these 3 had undergone palliative treatment. The chest roentgenograms of one child with complete transposition and a VSD demonstrate the dramatic improvement in the congestive heart failure after the two-staged correction (Fig. 2). Surgical experience. Bleeding problems were encountered in 3 patients. One patient (Case 3) exsanguinated from the distal anastomosis line and required additional sutures for hemostasis. His postoperative course was stormy; low cardiac output ensued, accompanying persistent hypokalemia. Despite daily administration of potassium chloride, ventricular fibrillation occurred repeatedly (once or twice a day) until he died on the eighth postoperative day. Postmortem examination revealed that the distal anastomosis orifice was extremely small, about 5 mm. in diameter. Hemorrhage was controlled in the other 2 patients without serious sequelae; one patient bled from the cardiac end of the divided pulmonary artery, and the other from the proximal anastomosis line. Preoperative laboratory findings of these 3 patients had ruled out the possiblity of hemorrhagic diathesis. Anatomy. Of the 4 patients whose VSD's were enlarged, one died of low cardiac output syndrome characterized by refractory low blood pressure and resultant renal shutdown. This patient was an infant girl, and her death could be attributed to the small heart rather than to maneuvers of the defect. Anatomic complexity was the basis for two of the operative deaths: One involved multiple VSD's and unilateral absence of a pulmonary artery and the other involved a TaussigBing malformation with advanced pulmonary obstruc-
tive disease. In addition to the anatomic complexity in both cases, the VSD was complicated by a tricuspid valve. The association of a hypoplastic left pulmonary artery allowed successful conduit repairs in one patient (Case 2); the preoperative and postoperative angiocardiograms of this patient are shown in Fig. 3. The child with Taussig-Bing malformation and an uncomplicated VSD survived the operation. Although reoperation was needed to manage a residual left-toright shunt, the patient was doing well 5 months after the first surgical intervention. The 9 patients followed up for one year or longer after open-heart surgery remain asymptomatic without the aid of medication. No late complications have appeared except for serum hepatitis, fever of unknown cause, and hematoma at the site of arterial cannulation. Mild calcification was detected by roentgenography in the region of the aortic homograft, yet there is no evidence of progressive deterioration. In all of the 9 patients studied, postoperative cathetherization and angiocardiograms demonstrated good-to-excellent function of the xenograft pulmonary valve mounted on the Dacron tubes utilized for reconstruction of the right ventricular outflow tract. Discussion
Theoretically, the Rastelli operation can be applied to any form of the transposition anomaly. Practically, however, the results attained suggest that its use must be evaluated in terms of the risks involved. The age and weight of the patient influence the immediate operative results. The timing of the operation, therefore, must be considered. After repair, the right ventricle invariably incurs
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■
-
*
■
■
■
Fig. 2. Roentgenograms of a child with complete transposition of great arteries and ventricular septal defect. A, Three months after birth, just before the patient underwent palliative treatment with pulmonary banding and closed atrioseptectomy. Cardiac enlargement with increased pulmonary vasculature is manifest. B, At the age of 7 years after total correction. The heart is of normal size, and pulmonary congestion is remarkably improved. several burdens. These include (1) elevated pulmonary vascular resistance, (2) regurgitant volume from the dead space of the external conduit used, (3) the loss of a contractile myocardial mass associated with a semicircular ventriculotomy, and (4) reduction of the right ventricular compartment due to the creation of an internal conduit. Early surgical intervention seems to be helpful in managing the pulmonary vascular obstructive disease because the disease usually progresses with age. 8 However, unfavorable effects of the other three factors on the right ventricular performance are relatively intensified in a smaller heart. The high operative mortality rate in infants and younger children is unlikely to justify the initial hope that a valved external conduit of adult size would permit adequate output as the patient grows.6 McGoon and associates9 reported a larger series of conduit repairs in which the operative mortality rate in patients of lower age group (less than 4 years) with transposition complexes was 82 per cent; this rate was
twice as high as the 42 per cent noted for patients of the same age group with either truncus arteriosus or pulmonary atresia. This difference in risk between TGA and lesions with normally related great arteries probably represents the decreased capacity of the right ventricle in the group with transposition, which resulted from the formation of an interventricular tunnel within the right ventricle. In contrast, patients with transposition who were between 5 and 12 years of age had excellent operative results, with a mortality rate of only 6 per cent. In our series, the effect of age was much more dominant. Thus, surgical trauma related to conduit repairs may seriously affect a small heart but is negligible in the heart of a reasonable size. The concept of the optimal time for operation emphasizes the importance of the palliative treatment in infancy and early childhood, when surgical therapy is required. About one half of the patients in the present series had benefited from various types of palliative procedures, and we believe that total correction has
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Conduit repairs of transposition complexes
575
Fig. 3. Angiocardiograms of a 7-year-old boy with complete transposition of great arteries, VSD, and pulmonary stenosis. A, Preoperative lateral view. Pulmonary trunk located posterior to enlarged aorta is markedly hypoplastic. B, Postoperative anteroposterior view. Right ventricle restores normal continuity with pulmonary artery. Left pulmonary artery shows moderate hypoplasia. been done safely after intervals of 7 to 9 years. A systemic-pulmonary artery shunt is useful in palliating patients who have decreased pulmonary blood flow owing to severe pulmonary stenosis. An event that occurred during operation in one of our patients exemplified the rationale behind the conduit repairs. Pulmonary stenosis associated with transposition defects is characterized, with few exceptions, by the marked hypoplasias of either the pulmonary arteries or the annulus, or both, in addition to pulmonary valvular and infundibular obstruction, as typically seen in Fig. 3. Choice of an appropriate means for repair of the diseased pulmonary valve and artery is often difficult, because no one can know whether or not the repair has been successfully accomplished until the pressure measurements are made after discontinuation of cardiopulmonary bypass. Fortunately, the patient in our series in whom the conventional methods had failed to give a satisfactory relief of the pulmonary stenosis was saved with subsequent conduit replacement of the pulmonary
outflow tract. Nonetheless, this is not recommended as a standard policy because the resultant prolonged bypass generally carries a high risk, especially in moribund patients. A controversy exists concerning the benefits of atrial septostomy or septectomy. This procedure has been established as a lifesaving measure10' n for babies born with transposition defects, but there is a growing skepticism of its value. Shaher12 observed in pathological specimens that the addition of an atrial septal defect to transposition of the great arteries and VSD had shortened life expectancy. Similarly, McGoon and co-workers9 pointed out a higher operative risk in patients with TGA and a natural or surgically created atrial septal defect. Our experience in the present series was too small to obtain useful information regarding this problem; the issue awaits further documentation. The successful one-stage correction of the TaussigBing malformation unassociated with pulmonary stenosis in one patient at the age of 6 years supports the
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5 7 6 Imamura et al.
concept that the intracardiac repair is feasible with acceptable risks so long as the pulmonary-systemic resistance ratio is 0.6 or less. 1 3 Most patients without pulmonary stenosis require surgical management in the earliest stage of life. The availability of palliative pulmonary banding 14 makes the Rastelli operation useful in patients with absence of the associated pulmonary stenosis, as demonstrated in our 2 patients, as well as in the experience of McGoon and associates. 9 This staging approach seems to compete favorably with other available corrective procedures. A troublesome problem of this procedure is postoperative bleeding. Cyanosed patients who have a hematocrit value of 65 per cent or more may be at a high risk of postoperative bleeding. 15 However, as our experience increases, this complication should be less frequent. There are certain anatomic complexities that compromise creation of a satisfactory internal conduit. Moore and colleagues 16 described 3 patients with TGA, VSD, and pulmonary stenosis who were treated with tricuspid or mitral valve replacement after conduit repair. Our 5 anatomic study disclosed that 60 per cent of the 32 hearts with TGA and VSD had a VSD which was partially overhung by the tricuspid valve. This type of anatomic variant was discovered in only 2 of the 14 patients in the present series. Essential to the proper selection of patients for operation is the precise and detailed interpretation of preoperative angiocardiographic findings with regard to type and position of the associated VSD as well as to the size of the right ventricular cavity. A few studies 1 7 - 1 9 have reported a tendency in aortic homografts for massive calcification or pseudoaneurysmal dilatation to develop when the homograft is placed in the pulmonary outflow tract for periods of several months. However, the xenograft porcine valve incorporated into a Dacron tube apparently does not have this shortcoming, 20 although further long-term observations are needed. Consequently, we continue to regard the Rastelli operation as the technique of choice in patients with transposition who have favorable anatomy. REFERENCES 1 Rastelli, G. C , McGoon, D. C , and Wallace, R. B.: Anatomic Correction of Transposition of the Great Arteries With Ventricular Septal Defect and Subpulmonary Stenosis, J. THORAC. CARDIOVASC. SURG. 58: 545, 1969.
2 Kirklin, J. W., Barcia, A., Deverall, P. B., Kouchoukos, N. T., and Bargeron, L. M., Jr.: Surgical Treatment of Complex Forms of Transposition, Br. Heart J. 33: 73, 1971 (Suppl.).
3 Breckenridge, I. M., Stark, J., Oelert, H., and Waterston, D. J.: Transposition of the Great Arteries With Ventricular Septal Defect and Pulmonary Stenosis Treated by the Rastelli Operation, Z. Kinderchir. Grenz. 11: 205, 1972. 4 Gonzalez-Lavin, L., and Sparrow, A. W.: Dacron Conduit With a Stented Porcine Xenograft Valve in the Anatomic Correction of Transposition of the Great Arteries and Subpulmonary Stenosis, Thorax 30: 644, 1975. 5 Imamura, E. S., Morikawa, T., Tatsuno, K., Konno, S., Arai, T., and Sakakibara, S.: Surgical Considerations of Ventricular Septal Defect Associated With Complete Transposition of the Great Arteries and Pulmonary Stenosis: With Special Reference to the Rastelli Operation, Circulation 44: 914, 1971. 6 Imamura, E. S., Tatsuno, K., and Sakakibara, S.: Heterologous Pulmonary Valve and Prosthetic Tube as a Substitute for Right Ventricular Outflow, Surgery 69: 716, 1971. 7 Imamura, E. S., Konno, S., Arai, T., and Sakakibara, S.: Composite Graft of Heterologous Pulmonary Valve and Prosthetic Tube for the Reconstruction of Right Ventricular Outflow Tract: Clinical Applications in Four Patients, J.
THORAC.
CARDIOVASC.
SURG.
63: 747,
1972. 8 Ferencz, C : Transposition of the Great Vessels: Pathophysiologic Considerations Based Upon a Study of the Lungs, Circulation 33: 232, 1966. 9 McGoon, D. C , Wallace, R. B., and Danielson, G. K.: The Rastelli Operation: Its Indications and Results, J. THORAC. CARDIOVASC. SURG. 65: 65, 1973.
10 Cornell, W. P., Maxwell, R. E., Haller, J. A., and Sabiston, D. C : Results of the Blalock-Hanlon Operation in 90 Patients With Transposition of the Great Vessels, J. THORAC. CARDIOVASC. SURG. 52: 525, 1966.
11 Rashkind, W. J., and Miller, W. W.: Transposition of the Great Arteries: Results of Palliation by Balloon Atrioseptostomy in Thirty-One Infants, Circulation 38: 453, 1968. 12 Shaher, R. M.: Complete Transposition of the Great Arteries, New York, 1973, Academic Press, Inc., p. 418. 13 McGoon, D. C , Rastelli, G. C , and Wallace, R. B.: Discontinuity Between Right Ventricle and Pulmonary Artery: Surgical Treatment, Ann. Surg. 172: 680, 1970. 14 Stark, J., Tynan, M., Tatooles, C. J., Aberdeen, E., and Waterston, D. J.: Banding of the Pulmonary Artery for Transposition of the Great Arteries and Ventricular Septal Defect, Circulation 41: 116, 1970 (Suppl. II). 15 Cleland, W., Goodwin, J., McDonald, L., and Ross, D.: Medical and Surgical Cardiology, Oxford, 1969, Blackwell Scientific Publications. 16 Moore, C. H., Martelli, V., and Ross, D. N.: Reconstruction of Right Ventricular Outflow Tract With a Valved Conduit in 75 Cases of Congenital Heart Disease, J. THORAC. CARDIOVASC. SURG. 71: 11, 1976.
17 Brawley, R. K., Gardner, T. J., Donahoo, J. S., Neill, C A., Rowe, R. D., and Gott, V. L.: Late Results After
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Right Ventricular Outflow Tract Reconstruction With Aortic Root Homografts, J. THORAC. CARDIOVASC. SURG. 64: 314,
1972.
18 Park, S. C , Neches, W. H., Lenox, C. C , Zuberbuhler, J. R., and Bahnson, H. T.: Massive Calcification and Obstruction in a Homograft After the Rastelli Procedure for Transposition of Great Arteries, Am. J. Cardiol. 32: 860, 1973. 19 Kaplan, S., McKinivan, E., Helmsworth, J. A., Bend-
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ing, G., Ill, Schwartz, D. C , and Schreiber, J. T.: Complications Following Homograft Replacement of the Right Ventricular Outflow Tract, Ann. Thorac. Surg. 18: 250, 1974. 20 Bowman, F. O., Jr., Hancock, W. D., and Malm, J. R.: A Valve-Containing Dacron Prosthesis: Its Use in Restoring Pulmonary Artery-Right Ventricular Continuity, Arch. Surg. 107: 724, 1973.
Eisaburo Imamura, M . D . , * Tetsuo Morikawa, M.D., Katsuhiko Tatsuno, M.D., Kenji Okamoto, M.D.,** Yasuharu Imai, M . D . , and Souji Konno, M . D . , t Tokyo, Japan
V arious surgical approaches are available for correction of the transposition anomaly. The choice of an appropriate procedure depends primarily on the associated lesions. The principle of repair presented by Rastelli and colleagues 1 in 1969 has allowed for the correction of complex transposition anomalies. 2 - 4 The Rastelli procedure redirects both ventricular outflows by closing the ventricular septal defect (VSD) so as to separate the aortic orifice from the right ventricle and by using an external valved conduit to restore normal continuity between the right ventricle and the pulmonary artery. Thus an " a n a t o m i c " correction is achieved. At the Heart Institute of Japan and Tokyo Women's Medical College from January, 1970, through December, 1975, we have used this technique on 14 patients to correct transposition complexes. Ten patients had From the Department of Cardiovascular Surgery, Tokyo Women's Medical College and the Heart Institute of Japan, Tokyo, Japan. Received for publication July 12, 1976. Accepted for publication Dec. 13, 1976. Address for reprints: Dr. K. Tatsuno, Tokyo Women's Medical College, Shinjukuku, Tokyo 162, Japan. ♦Present address: Mayo Graduate School of Medicine, Rochester, Minn. 55901. **Present address: Tsukuba University School of Medicine, Ibargi, Japan. tDr. Konno died May 25, 1976.
570
complete transposition of the great arteries, and 4 had double-outlet right ventricles; all had associated VSD's. Ten of the 14 also had pulmonary stenosis. Materials and methods The present series comprises four groups (Table I): Group I, 8 patients who had complete (dextro-) transposition of the great arteries (d-TGA) with VSD and pulmonary stenosis; Group II, 2 patients who had d-TGA with VSD; Group III, 2 patients who had double-outlet right ventricle with subaortic VSD and pulmonary stenosis; and Group IV, 2 patients who had double-outlet right ventricle with subpulmonary VSD (Taussig-Bing malformation). The 14 patients shared a common anatomic feature—the aorta arose from the right ventricle, situated anterior to or along side the pulmonary artery. Patients with inverted ventricle or single ventricle were excluded from the series. Accordingly, the closure of the VSD was consistent in nature and is schematically illustrated in Fig. 1. The series included 7 boys and 7 girls whose ages ranged from 13 months to 18 years, with a mean age of 8 years. The body weights ranged from 8 to 53 kilograms and averaged 21 kilograms. All patients were symptomatically severely ill with cyanosis; the average preoperative hematocrit value was 60 per cent. Six patients had been treated with a total of nine palliative operations 7 to 9 years before total correction: four
Volume 73 Number 4 April, 1977
systemic-pulmonary artery anastomoses, three atrioseptectomies, and two pulmonary arterial banding procedures. The heart was exposed through a midline incision. Patients were placed on cardiopulmonary bypass with moderate hypothermia between 28 and 30° C. An elliptic opening was made on the anterior wall of the right ventricle. The VSD was enlarged (if it was not large enough) and was closed with the use of a Teflon patch so that blood from the left ventricle could electively be ejected into the ascending aorta. Because a largerthan-normal aorta is usual in the heart in which a VSD and pulmonary stenosis coexist, a defect size that was about 80 per cent or more of the individual aortic orifice was considered to be large enough. An aortic homograft, including the aortic valve, was used for reconstruction of the right ventricular outflow tract of the first patient.5 A xenograft pulmonary valve incorporated into woven Dacron tubes was employed in the subsequent 13 patients. The latter type of graft has an angled structure that resembles the natural outflow tract of the right ventricle. Its fabrication and clinical application have been discussed previously.6, 7 Group I: d-TGA with VSD and pulmonary stenosis. Six of the 8 patients with this anomaly underwent one-stage correction. The remaining 2 children were treated palliatively, one with a subclavianpulmonary artery anastomosis (Blalock-Taussig shunt) and the other with an atrioseptectomy. The latter procedure was done with the use of extracorporeal circulation. In 7 patients at operation, a VSD was found lying immediately beneath the aortic orifice. Of these 7, 2 required anterior enlargement of the VSD. In one patient (Case 4), two separate VSD's were located inferior to the crista supraventricularis, with the posterior defect being partially overhung by the tricuspid valve. To simplify the technique, the papillary muscle with chordae tendineae adherent to a well-developed muscular column that separated the defects was temporarily detached while the VSD's were being closed en bloc. Afterward, the divided end of the papillary muscle was reattached onto the wall of the Teflon internal conduit. All but one patient had combined valvular and subvalvular pulmonary stenosis. Two of the 8 patients had deformity of the left pulmonary artery (one with absent artery and one with hypoplasia). The other 6 patients had valvular stenosis only. Group II: d-TGA with VSD. Two children, ages 7 and 9 years, had undergone palliation with pulmonary banding and atrioseptectomy (Blalock-Hanlon procedure) at 3 months and 2 months of age, respectively. In both, the VSD was of infracristal type, requiring an-
Conduit repairs of transposition complexes
57 1
terosuperior enlargement. An interventricular tunnel was created without difficulty. The pulmonary valve and subvalvular tract were normally developed, with the pulmonary trunk distal to the banding being markedly dilated. In one child, the pulmonary trunk was transsected at the debanded site, the proximal end of which was oversewn. An external valved conduit was anastomosed to the distal end of the pulmonary artery in end-to-end fashion. In the other patient, the pulmonary trunk was tied at its root, and a longitudinal incision, 2.5 cm. long, was made distal to the ligature. The external conduit was anastomosed in end-to-side fashion. Group III: Double-outlet right ventricle with subaortic VSD and pulmonary stenosis. Two patients, ages 11 and 9 years, had undergone palliation with a Blalock-Taussig shunt at the age of 4 years and 13 months, respectively. A Waterston shunt was added in the latter patient 3 years later. In one child, surgical intervention initially was attempted to relieve the pulmonary stenosis by valvotomy and infundibulectomy. However, because a high gradient persisted, bypass was reinstituted and a conduit was inserted. Group IV: Double-outlet right ventricle with subpulmonary VSD. Two children, both 6 years of age, were seen initially because of frequent episodes of respiratory distress. The diagnosis was established at open-heart surgery. One child underwent emergency operation. A large VSD was located immediately beneath the pulmonary valve. Because the lower half of the VSD was overhung by the tricuspid valve, creation of the interventricular tunnel necessitated detachment of the chordae tendineae. The main pulmonary artery was ligated at its root, and an external conduit was inserted. The other patient was in a relatively stable state, enough so as to permit thorough diagnostic measures to be taken. Postoperative catheterization revealed pulmonary hypertension (90/50 mm. Hg) with a left-to-right shunt of 80 per cent and a pulmonarysystemic resistance ratio of 0.3. The pulmonary trunk was disconnected from the right ventricle by sewing each commissure of the pulmonary valve. After closure of the VSD, the continuity between the right ventricle and the pulmonary artery was re-established with an external valved conduit. The persistent ductus arteriosus was closed with a suture from within the pulmonary artery. Results Survival. Of the 14 patients, 4 died within 8 days after the operation. The operative mortality rate was 29 per cent. There have been no late deaths among the 10
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Table I. Patients with transposition complexes undergoing Rastelli repair
Case
Sex and age (yr.)
Weight (kg.)
Preop. hematocrit
(%)
Previous palliation
Date of operation
VSD
Pulmonary stenosis
1
M, 12
26
64
2
M, 7
16
72
Group I: d-TGA * with VSD and pulmonary stenosis 1/19/70 Supracristal Blalock-Taussig (5 yr.) 5/24/72 None Supracristal
3
M, 3
13
72
None
6/5/72
Supracristal
4
F, 4
13
74
None
7/3/72
Multiple, complicated
5
F, 1
8
45
None
6/19/73
6
M, 7
18
69
None
9/12/73
Supracristal, "enlarged" Supracristal
7
F, 8
20
66
None
10/11/73
8
F, 18
53
56
Open atrioseptectomy (11 yr.)
11/5/73
9
M,7
20
70
10
M, 9
21
58
11
M, 11
25
12
M, 9
20
13
F, 6
12
55
Group IV: Double-outlet right ventricle with VSD None 4/17/74 Subpulmonary
—
14
M, 6
16
44
None
-
Supracristal, "enlarged" Supracristal
Valvular and subvalvular Valvular and subvalvular hypoplasia of left pulmonary artery Valvular and subvalvular Valvular and subvalvular absence of left pulmonary artery Valvular Valvular and subvalvular Valvular and subvalvular Valvular and subvalvular
Group II: d-TGA with VSD Infracristal, 7/5/74 Closed artrioseptectomy and pul"enlarged" monary artery banding Infracristal, 2/12/75 Closed atrioseptectomy and pul"enlarged" monary artery banding
Subpulmonary
Good (6 yr.) Excellent (4 yr.)
Died, arrhythmias Died, low cardiac output
Died, low cardiac output Excellent (3 yr.) Excellent (2'/2 yr.) Excellent (2 yr., 5 mo.) Excellent (1 yr., 9 mo.)
Excellent (1 yr., 2 mo.)
Group Ih : Double-outlet right ventricle with VSD and pulmonary stenosis 9/13/72 Blalock-Taussig Subaortic Valvular and 48 (4 yr.) subvalvular 42 Blalock-Taussig 12/6/74 Subaortic Valvular and (13 mo.) subvalvular Waterston (4 yr.)
10/22/75
Results (follow-up)
Excellent (3 yr., 9 mo.) Excellent (1 yr., 5 mo.)
Died, low cardiac output Good (5 mo.)
*d-TGA, Complete transposition of great arteries. VSD, Ventricular septal defect.
patients who survived the operation during follow-up periods that ranged from 5 months to 6 years. Age and weight. Of the 10 operative survivors, 9 were 5 years old or older, with the oldest being 18 years. In contrast, 3 children less than 4 years of age died. The body weight reflected this tendency: The 10 survivors weighed between 16 and 53 kilograms,
whereas the 4 patients who died weighed between 8 and 13 kilograms. Palliative operation. Of the 8 patients in whom the primary surgical intervention was conduit repair, 4 died. All 6 patients who had had effective palliation underwent successful operation. The palliative procedures did not cause recognizable hazards at open-heart
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Conduit repairs of transposition complexes
Normally Related Great Vessels
573
Transposed Great Vessels
Fig. 1. Diagrams illustrating the Rastelli conduit repair. Arrows indicate direction of blood flow after repair. Dotted areas delineaterightventricular cavity. Note that while both ventricular compartments remain unchanged after the ventricular septal defect is closed in the heart with normally related great vessels (A), the effective right ventricular cavity is reduced by creation of an interventricular tunnel in heart with transposition (B). surgery. Of the 4 patients who were born without pulmonary stenosis, 3 survived total correction; 2 of these 3 had undergone palliative treatment. The chest roentgenograms of one child with complete transposition and a VSD demonstrate the dramatic improvement in the congestive heart failure after the two-staged correction (Fig. 2). Surgical experience. Bleeding problems were encountered in 3 patients. One patient (Case 3) exsanguinated from the distal anastomosis line and required additional sutures for hemostasis. His postoperative course was stormy; low cardiac output ensued, accompanying persistent hypokalemia. Despite daily administration of potassium chloride, ventricular fibrillation occurred repeatedly (once or twice a day) until he died on the eighth postoperative day. Postmortem examination revealed that the distal anastomosis orifice was extremely small, about 5 mm. in diameter. Hemorrhage was controlled in the other 2 patients without serious sequelae; one patient bled from the cardiac end of the divided pulmonary artery, and the other from the proximal anastomosis line. Preoperative laboratory findings of these 3 patients had ruled out the possiblity of hemorrhagic diathesis. Anatomy. Of the 4 patients whose VSD's were enlarged, one died of low cardiac output syndrome characterized by refractory low blood pressure and resultant renal shutdown. This patient was an infant girl, and her death could be attributed to the small heart rather than to maneuvers of the defect. Anatomic complexity was the basis for two of the operative deaths: One involved multiple VSD's and unilateral absence of a pulmonary artery and the other involved a TaussigBing malformation with advanced pulmonary obstruc-
tive disease. In addition to the anatomic complexity in both cases, the VSD was complicated by a tricuspid valve. The association of a hypoplastic left pulmonary artery allowed successful conduit repairs in one patient (Case 2); the preoperative and postoperative angiocardiograms of this patient are shown in Fig. 3. The child with Taussig-Bing malformation and an uncomplicated VSD survived the operation. Although reoperation was needed to manage a residual left-toright shunt, the patient was doing well 5 months after the first surgical intervention. The 9 patients followed up for one year or longer after open-heart surgery remain asymptomatic without the aid of medication. No late complications have appeared except for serum hepatitis, fever of unknown cause, and hematoma at the site of arterial cannulation. Mild calcification was detected by roentgenography in the region of the aortic homograft, yet there is no evidence of progressive deterioration. In all of the 9 patients studied, postoperative cathetherization and angiocardiograms demonstrated good-to-excellent function of the xenograft pulmonary valve mounted on the Dacron tubes utilized for reconstruction of the right ventricular outflow tract. Discussion
Theoretically, the Rastelli operation can be applied to any form of the transposition anomaly. Practically, however, the results attained suggest that its use must be evaluated in terms of the risks involved. The age and weight of the patient influence the immediate operative results. The timing of the operation, therefore, must be considered. After repair, the right ventricle invariably incurs
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■
-
*
■
■
■
Fig. 2. Roentgenograms of a child with complete transposition of great arteries and ventricular septal defect. A, Three months after birth, just before the patient underwent palliative treatment with pulmonary banding and closed atrioseptectomy. Cardiac enlargement with increased pulmonary vasculature is manifest. B, At the age of 7 years after total correction. The heart is of normal size, and pulmonary congestion is remarkably improved. several burdens. These include (1) elevated pulmonary vascular resistance, (2) regurgitant volume from the dead space of the external conduit used, (3) the loss of a contractile myocardial mass associated with a semicircular ventriculotomy, and (4) reduction of the right ventricular compartment due to the creation of an internal conduit. Early surgical intervention seems to be helpful in managing the pulmonary vascular obstructive disease because the disease usually progresses with age. 8 However, unfavorable effects of the other three factors on the right ventricular performance are relatively intensified in a smaller heart. The high operative mortality rate in infants and younger children is unlikely to justify the initial hope that a valved external conduit of adult size would permit adequate output as the patient grows.6 McGoon and associates9 reported a larger series of conduit repairs in which the operative mortality rate in patients of lower age group (less than 4 years) with transposition complexes was 82 per cent; this rate was
twice as high as the 42 per cent noted for patients of the same age group with either truncus arteriosus or pulmonary atresia. This difference in risk between TGA and lesions with normally related great arteries probably represents the decreased capacity of the right ventricle in the group with transposition, which resulted from the formation of an interventricular tunnel within the right ventricle. In contrast, patients with transposition who were between 5 and 12 years of age had excellent operative results, with a mortality rate of only 6 per cent. In our series, the effect of age was much more dominant. Thus, surgical trauma related to conduit repairs may seriously affect a small heart but is negligible in the heart of a reasonable size. The concept of the optimal time for operation emphasizes the importance of the palliative treatment in infancy and early childhood, when surgical therapy is required. About one half of the patients in the present series had benefited from various types of palliative procedures, and we believe that total correction has
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Conduit repairs of transposition complexes
575
Fig. 3. Angiocardiograms of a 7-year-old boy with complete transposition of great arteries, VSD, and pulmonary stenosis. A, Preoperative lateral view. Pulmonary trunk located posterior to enlarged aorta is markedly hypoplastic. B, Postoperative anteroposterior view. Right ventricle restores normal continuity with pulmonary artery. Left pulmonary artery shows moderate hypoplasia. been done safely after intervals of 7 to 9 years. A systemic-pulmonary artery shunt is useful in palliating patients who have decreased pulmonary blood flow owing to severe pulmonary stenosis. An event that occurred during operation in one of our patients exemplified the rationale behind the conduit repairs. Pulmonary stenosis associated with transposition defects is characterized, with few exceptions, by the marked hypoplasias of either the pulmonary arteries or the annulus, or both, in addition to pulmonary valvular and infundibular obstruction, as typically seen in Fig. 3. Choice of an appropriate means for repair of the diseased pulmonary valve and artery is often difficult, because no one can know whether or not the repair has been successfully accomplished until the pressure measurements are made after discontinuation of cardiopulmonary bypass. Fortunately, the patient in our series in whom the conventional methods had failed to give a satisfactory relief of the pulmonary stenosis was saved with subsequent conduit replacement of the pulmonary
outflow tract. Nonetheless, this is not recommended as a standard policy because the resultant prolonged bypass generally carries a high risk, especially in moribund patients. A controversy exists concerning the benefits of atrial septostomy or septectomy. This procedure has been established as a lifesaving measure10' n for babies born with transposition defects, but there is a growing skepticism of its value. Shaher12 observed in pathological specimens that the addition of an atrial septal defect to transposition of the great arteries and VSD had shortened life expectancy. Similarly, McGoon and co-workers9 pointed out a higher operative risk in patients with TGA and a natural or surgically created atrial septal defect. Our experience in the present series was too small to obtain useful information regarding this problem; the issue awaits further documentation. The successful one-stage correction of the TaussigBing malformation unassociated with pulmonary stenosis in one patient at the age of 6 years supports the
The Journal of Thoracic and Cardiovascular Surgery
5 7 6 Imamura et al.
concept that the intracardiac repair is feasible with acceptable risks so long as the pulmonary-systemic resistance ratio is 0.6 or less. 1 3 Most patients without pulmonary stenosis require surgical management in the earliest stage of life. The availability of palliative pulmonary banding 14 makes the Rastelli operation useful in patients with absence of the associated pulmonary stenosis, as demonstrated in our 2 patients, as well as in the experience of McGoon and associates. 9 This staging approach seems to compete favorably with other available corrective procedures. A troublesome problem of this procedure is postoperative bleeding. Cyanosed patients who have a hematocrit value of 65 per cent or more may be at a high risk of postoperative bleeding. 15 However, as our experience increases, this complication should be less frequent. There are certain anatomic complexities that compromise creation of a satisfactory internal conduit. Moore and colleagues 16 described 3 patients with TGA, VSD, and pulmonary stenosis who were treated with tricuspid or mitral valve replacement after conduit repair. Our 5 anatomic study disclosed that 60 per cent of the 32 hearts with TGA and VSD had a VSD which was partially overhung by the tricuspid valve. This type of anatomic variant was discovered in only 2 of the 14 patients in the present series. Essential to the proper selection of patients for operation is the precise and detailed interpretation of preoperative angiocardiographic findings with regard to type and position of the associated VSD as well as to the size of the right ventricular cavity. A few studies 1 7 - 1 9 have reported a tendency in aortic homografts for massive calcification or pseudoaneurysmal dilatation to develop when the homograft is placed in the pulmonary outflow tract for periods of several months. However, the xenograft porcine valve incorporated into a Dacron tube apparently does not have this shortcoming, 20 although further long-term observations are needed. Consequently, we continue to regard the Rastelli operation as the technique of choice in patients with transposition who have favorable anatomy. REFERENCES 1 Rastelli, G. C , McGoon, D. C , and Wallace, R. B.: Anatomic Correction of Transposition of the Great Arteries With Ventricular Septal Defect and Subpulmonary Stenosis, J. THORAC. CARDIOVASC. SURG. 58: 545, 1969.
2 Kirklin, J. W., Barcia, A., Deverall, P. B., Kouchoukos, N. T., and Bargeron, L. M., Jr.: Surgical Treatment of Complex Forms of Transposition, Br. Heart J. 33: 73, 1971 (Suppl.).
3 Breckenridge, I. M., Stark, J., Oelert, H., and Waterston, D. J.: Transposition of the Great Arteries With Ventricular Septal Defect and Pulmonary Stenosis Treated by the Rastelli Operation, Z. Kinderchir. Grenz. 11: 205, 1972. 4 Gonzalez-Lavin, L., and Sparrow, A. W.: Dacron Conduit With a Stented Porcine Xenograft Valve in the Anatomic Correction of Transposition of the Great Arteries and Subpulmonary Stenosis, Thorax 30: 644, 1975. 5 Imamura, E. S., Morikawa, T., Tatsuno, K., Konno, S., Arai, T., and Sakakibara, S.: Surgical Considerations of Ventricular Septal Defect Associated With Complete Transposition of the Great Arteries and Pulmonary Stenosis: With Special Reference to the Rastelli Operation, Circulation 44: 914, 1971. 6 Imamura, E. S., Tatsuno, K., and Sakakibara, S.: Heterologous Pulmonary Valve and Prosthetic Tube as a Substitute for Right Ventricular Outflow, Surgery 69: 716, 1971. 7 Imamura, E. S., Konno, S., Arai, T., and Sakakibara, S.: Composite Graft of Heterologous Pulmonary Valve and Prosthetic Tube for the Reconstruction of Right Ventricular Outflow Tract: Clinical Applications in Four Patients, J.
THORAC.
CARDIOVASC.
SURG.
63: 747,
1972. 8 Ferencz, C : Transposition of the Great Vessels: Pathophysiologic Considerations Based Upon a Study of the Lungs, Circulation 33: 232, 1966. 9 McGoon, D. C , Wallace, R. B., and Danielson, G. K.: The Rastelli Operation: Its Indications and Results, J. THORAC. CARDIOVASC. SURG. 65: 65, 1973.
10 Cornell, W. P., Maxwell, R. E., Haller, J. A., and Sabiston, D. C : Results of the Blalock-Hanlon Operation in 90 Patients With Transposition of the Great Vessels, J. THORAC. CARDIOVASC. SURG. 52: 525, 1966.
11 Rashkind, W. J., and Miller, W. W.: Transposition of the Great Arteries: Results of Palliation by Balloon Atrioseptostomy in Thirty-One Infants, Circulation 38: 453, 1968. 12 Shaher, R. M.: Complete Transposition of the Great Arteries, New York, 1973, Academic Press, Inc., p. 418. 13 McGoon, D. C , Rastelli, G. C , and Wallace, R. B.: Discontinuity Between Right Ventricle and Pulmonary Artery: Surgical Treatment, Ann. Surg. 172: 680, 1970. 14 Stark, J., Tynan, M., Tatooles, C. J., Aberdeen, E., and Waterston, D. J.: Banding of the Pulmonary Artery for Transposition of the Great Arteries and Ventricular Septal Defect, Circulation 41: 116, 1970 (Suppl. II). 15 Cleland, W., Goodwin, J., McDonald, L., and Ross, D.: Medical and Surgical Cardiology, Oxford, 1969, Blackwell Scientific Publications. 16 Moore, C. H., Martelli, V., and Ross, D. N.: Reconstruction of Right Ventricular Outflow Tract With a Valved Conduit in 75 Cases of Congenital Heart Disease, J. THORAC. CARDIOVASC. SURG. 71: 11, 1976.
17 Brawley, R. K., Gardner, T. J., Donahoo, J. S., Neill, C A., Rowe, R. D., and Gott, V. L.: Late Results After
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Right Ventricular Outflow Tract Reconstruction With Aortic Root Homografts, J. THORAC. CARDIOVASC. SURG. 64: 314,
1972.
18 Park, S. C , Neches, W. H., Lenox, C. C , Zuberbuhler, J. R., and Bahnson, H. T.: Massive Calcification and Obstruction in a Homograft After the Rastelli Procedure for Transposition of Great Arteries, Am. J. Cardiol. 32: 860, 1973. 19 Kaplan, S., McKinivan, E., Helmsworth, J. A., Bend-
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ing, G., Ill, Schwartz, D. C , and Schreiber, J. T.: Complications Following Homograft Replacement of the Right Ventricular Outflow Tract, Ann. Thorac. Surg. 18: 250, 1974. 20 Bowman, F. O., Jr., Hancock, W. D., and Malm, J. R.: A Valve-Containing Dacron Prosthesis: Its Use in Restoring Pulmonary Artery-Right Ventricular Continuity, Arch. Surg. 107: 724, 1973.