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Left ventricular and biventricular extracardiac conduits
Left ventricular and biventricular extracardiac conduits The insertion of an extracardiac conduit from the right ventricle has gained extensive success during the past decade. This report concerns the application of such a conduit from the left ventricle. Its use in four types of anomalies is described: (I) left ventricular outflow hypoplasia, (2) transposition of the great arteries with ventricular inversion and associated pulmonary stenosis, (3) complex anomalies involving double-outlet right ventricle wherein construction of an intracardiac tunnel is not feasible, and (4) transposition of the great arteries with intact ventricular septum and severe pulmonary stenosis. The correction of the last two mentioned anomalies involves the insertion of two parallel conduits, one from each ventricle to its appropriate great artery. The transposition anomaly may alternatively be corrected by combined Mustard repair and a left ventricle-to-pulmonary artery extracardiac conduit.
Dwight C. McGoon, M.D., Rochester,
Minn.
.Louring the 1960's, the concept was developed of using a conduit to establish an outflow tract connecting the right ventricle to the pulmonary trunk or arteries. The technique was applied in correction of pulmonary atresia, 1,2 truncus arteriosus,3 and transposition of the great arteries associated with ventricular septal defect and pulmonary stenosis.4, 5 The current hospital mortality rate of five to ten per cent for operations involving a conduit from the right ventricle to the pulmonary artery, the favorable follow-up results for the limited periods available thus far,6~8 and the fact that alternative corrective techniques are not available for these and related conditions all establish this procedure securely in the armamentarium of the cardiac surgeon. This success justifies exploration for other conditions which presently may be inadequately managed surgically and for which a conduit provides an appealing approach. Attention is directed to the possibility of inserting a valved conduit from the left ventricle to the appropriate great artery. Four possibilities present themselves. Situations exist in which hypoplasia of the left ventricular outflow tract cannot be adequately relieved by conventional reconstructive or replacement techniques. This is true in congenital aortic stenosis asFrom the Mayo Clinic and Mayo Foundation, Rochester, Minn. 55901. Received for publication Jan. 16, 1976. Accepted for publication Feb. 17, 1976.
sociated with hypoplasia of the subvalvular and supravalvular zones and of the aortic annulus.9 It is also often true in pulmonary stenosis when transposition and ventricular inversion (corrected transposition) are pressent, a condition in which dextrocardia and doubleoutlet right ventricle are often associated.10 Other situations exist in which the aorta originates from the right ventricle but in which an intracardiac repair is not feasible for directing left ventricular output to the aorta because of the absence of a ventricular septal defect or an inappropriately situated ventricular septal defect. This is true in certain types of double-outlet right ventricle, for example, those cases associated with complete atrioventricular canal (a combination not previously successfully corrected), and in transposition of the great arteries with intact ventricular septum, especially when associated severe pulmonary stenosis mitigates against the Mustard operation alone. A possible repair applicable in these last two situations involves insertion of twin conduits, one from the right ventricle to the pulmonary artery and one from the left ventricle to the aorta. Cases that illustrate the application of these four approaches are presented. Congenital aortic stenosis associated with hypoplasia of subvalvular and supravalvular zones and of the aortic annulus CASE 1. The boy was 7 years old at the time of his operation at the Mayo Clinic. He had had evidence of congenital aortic stenosis and coarctation since the age of 3 7
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Fig. 1. Case I. A, Intraoperative appearance of conduit passing from apex of left ventricle (right upper end of conduit) to ascending aorta (anastomosis to aorta not seen in left lower corner). Valve-bearing segment of conduit can be identified in the center. B, Postoperative roentgenogram of chest taken at hospital dismissal. Table I. Serial cardiac catheterizations in patient with congenital aortic stenosis associated hypoplasia of subvalvular and supravalvular zones and of the aortic annulus First operation (age 6 yr.)
LVP (mm. Hg) Ascending aorta pressure (mm. Hg) Peak systolic LV-aortic gradient (mm. Hg) Cardiac index (L./min./sq. M.)
with
Second operation (age 7 yr.)
At age 3 yr.
At age 6 yr.
Intraoperative, after repair
Preop.
Intraoperative, before repair
Intraoperative, after repair
LV not entered
-
-
218/10
200/0
90/15
-
-
-
99/59
110/65
80/45
-
135
65
119
90
10
-
-
-
4.6
-
-
Legend: LVP, Left ventricular pressure. LV, Left ventricle.
years. Easy fatigability and shortness of breath on exertion were his significant symptoms. Open-heart surgery had been performed elsewhere 1 year previously, at which time the hypoplastic left ventricular outflow tract was noted, and maximal relief had been obtained by incising both commissures of the bicuspid aortic valve. The child continued to tire easily and to have shortness of breath on exertion. Data from the serial cardiac catheterizations are given in Table I. Credit must be given the boy's cardiologist, Dr. Gilbert H. Blount, who, in recommending reoperation, indicated the possible appropriateness of the "Rastelli approach." In July, 1975, at the Mayo Clinic, aortotomy confirmed the presence of a hypoplastic left ventricular outflow tract, which was narrowest at the level of the aortic annulus. The separation of the two cusps was already complete to the
annulus. A 10 mm. Hegar dilator fit snugly in the annulus. No discrete subvalvular constriction was present. Both coronary arteries were cannulated, and the myocardium was perfused continuously. The apex of the left ventricle was elevated, the apical vent was removed, and a ventriculotomy was extended 5 cm. cephalad from the apical vent site, parallel to (and 1.5 cm. lateral to) the left anterior descending artery. The base of the anterior papillary muscle of the mitral valve could be seen just lateral to the cephalad extent of the ventriculotomy. The endocardial edge of the ventriculotomy was trimmed on both sides. A 25 mm. diameter Dacron conduit containing a porcine valve* was cut on a wide angle and anastomosed to the margins of the ventriculotomy. The distal end of the *Hancock Laboratories, Inc., Anaheim, Calif.
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-Infundibular chamber
Fig. 2. Diagram of repair of levotransposition of great arteries with ventricular inversion, ventricular septal defect, and pulmonary stenosis. Conduit has been inserted from anatomic left ventricle to pulmonary artery. This illustration was utilized in an earlier report of an operation performed by Kirklin more than a decade ago. (From Kiser, J. C , Ongley, P. A., Kirklin, J. W., Clarkson, P. M , and McGoon, D. C : Surgical Treatment of Dextrocardia With Inversion of Ventricles and Double-Outlet Right Ventricle, J. THORAC. CARDIOVASC. SURG. 55: 6, 1968, published by The C. V. Mosby Company.) conduit was appropriately trimmed obliquely and anastomosed to the aortotomy. Air was evacuated, and coronary cannulas were withdrawn as for any aortic valve procedure," except that a needle was also inserted in the uppermost point of the conduit to ensure against air entrapment there. Cardiac action and hemodynamics seemed excellent immediately. The left lateral portion of the pericardium was incised longitudinally to allow the conduit to bulge into the left pleural space (Fig. 1, A). Extracorporeal circulation lasted 107 minutes. The boy's postoperative course was uneventful, and he was dismissed to his home on the sixteenth postoperative day, receiving no medications. A Grade 1/6 systolic murmur was present over the right upper sternal border. A chest roentgenogram obtained just before hospital dismissal is shown in Fig. 1, B. The referring cardiologist reported continued satisfactory progress 6 weeks postoperatively. Consideration will be given in the future to repair of the typical coarctation. Pulmonary stenosis, transposition arteries, and ventricular inversion
of the
great
The technique of choice at our institution for the : correction of most hearts with this anomaly has for
several years involved the insertion of a conduit from the morphologic left ventricle (right-sided pulmonary ventricle). This approach was first employed many years ago at the Mayo Clinic by Kirklin, undoubtedly the first instance in which a conduit from the left ventricle was inserted. This case was reported in 1968, 10 and the illustration from that report, reproduced herein (Fig. 2), still suffices to illustrate the technique. A study of the late result of the series of patients treated in this manner is in progress. Double-outlet right ventricle, pulmonary stenosis, anterior aorta, complete atrioventricular canal, rudimentary AV valve leaflets, anomalous systemic venous connection, situs inversus dextrocardia, left Blalock-Taussig anastomosis, and asplenia CASE 2. The boy was 14 years old at the time of his corrective operation. He had been cyanotic since infancy. He underwent cardiac catheterization at the Mayo Clinic at the age of 5 months and again at the age of 5 years. Data at operation provided the diagnosis of situs inversus, doubleoutlet right ventricle, pulmonary stenosis, ventricular septal
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McGoon
Fig. 3. Case 2. Anatomic detail. The interior of morphologic right ventricle and right atrium. Atrioventricular valves have not been drawn in order to simplify the anatomy. Large central septal defect of complete atrioventricular canal is shown, along with double-outlet right ventricle, pulmonary stenosis, inferior vena cava to left atrium, bilateral superior venae cavae, one to each atrium, left Blalock-Taussig anastomosis, Dacron shunt from ascending aorta to pulmonary artery, and situs inversus totalis. defect, and atrial septal defect, as well as bilateral superior venae cavae. Because of increasingly severe cyanosis (hemoglobin level 18.8 Gm. per deciliter), a highly successful left Blalock-Taussig anastomosis was performed at the Mayo Clinic by Dr. John Kirklin when the patient was 5 years old. The complexity of the cardiac malformation dissuaded an attempt at complete repair for some years, but it was finally undertaken when he was 13 years old (1 year before actual correction). On this occasion, I found an associated complete atrioventricular canal deformity, as well as the anomalous connection of the inferior vena cava with the morphologic left atrium, by palpation within the heart. The presence of double-outlet right ventricle with the aorta anterior as well as pulmonary stenosis was confirmed. Previous attempts at repair of associated complete atrioventricular canal and double-oudet right ventricle had been unsuccessful. This lack of success, combined with the presence of the other associated anomalies and the possibility that further palliation could be achieved by a supplemental shunt procedure, led us to avoid establishing extracorporeal circulation. A Dacron arterial prosthesis was anastomosed between the ascending aorta and the left pulmonary artery. Unfortunately, palliation was not realized. During the
The Journal of Thoracic and Cardiovascular Surgery
subsequent year, progressively severe congestive heart failure, anasarca, cardiomegaly, and cardiac cachexia developed, primarily because of progressive regurgitation at the atrioventricular valve. In August, 1975, heart-lung bypass was instituted by cannulating the right external iliac artery and the left superior and inferior venae cavae via the right atrium.* The inferior cava penetrated the central area of the diaphragm and entered the left atrium directly in the midline (Fig. 3). The right superior vena cava was ligated, which resulted in no increment in right jugular venous pressure. The left subclavian artery was ligated, and the chronically occluded Dacron graft was disengaged from the aorta, later to be removed. A wide atriotomy was created. The presence of a complete atrioventricular canal deformity was confirmed, and a rudimentary atrioventricular valve leaflet, which did not conform to any of the classic types,12 was excised. A 16 mm. knitted Dacron arterial prosthesis was opened longitudinally and sutured about the inferior caval orifice and along the posterior aspect of the left atrium, so as to create a tunnel extending the inferior cava to the right atrium (Fig. 4). A composite prosthesis was fashioned, consisting of a large oval patch of intracardiac knitted Teflon and 27 mm. Hancock frame-mounted porcine valves sutured at slightly different levels on each side of the patch about 1.5 cm. above its lower (ventricular) rim (Fig. 5). This patch was first attached to the crest of the ventricular septum by use of interrupted silk sutures, as in the standard repair of complete atrioventricular canal.13 Next, the edges of the left and right Hancock valve frames, which were not attached to the patch, were sutured to the annuli of the mitral and tricuspid valves, respectively and sequentially. Next, the atrial edge of the septal patch was sutured to the rim of the atrial septum (except at the inferior caval tunnel, to which the septal patch was sutured). The intracardiac portion of the repair was then complete (Fig. 5), and the atriotomy site was closed. The left pulmonary artery was incised longitudinally from the left superior vena cava proximally to the origin of the pulmonary trunk. A 25 mm. Hancock conduit was anastomosed to this incision. A partial-occlusion clamp was applied to the anterior aspect of the ascending aorta, and a 3 cm. incision was made in the aorta, to which an obliquely cut, second Hancock conduit (also 25 mm. in diameter) was anastomosed. A left ventriculotomy was made in the manner described for Case 1, and the proximal end of the aortic conduit was anastomosed to it. Finally, a longitudinal right ventriculotomy was made, and the pulmonary conduit was anastomosed to it (Fig. 6). Flow into the aorta from the left ventricle via the conduit thus has access to the coronary arteries proximally as well as the distal aorta. Because the intra-aortic pressure is greater throughout the cardiac cycle than right ventricular pressure, the aortic valve remains closed at all times. This is an application of the concept developed independently by Damus,14 Kaye,15 and Stansel.16 Cardiopulmonary bypass lasted 250 minutes, and the aorta was cross-clamped on multiple occasions, totaling 76 *In this description, the laterality of the cavae and pulmonary arteries is indicated in accordance with their positions in the body, but the atria and ventricles, which are each in situs inversus, are named in accordance with their morphology.
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Fig. 4. Case 2. Anterior portion of heart has not been drawn in order to show both ventricles. Blalock-Taussig anastomosis has been ligated, as has right superior vena cava, and Dacron shunt has been divided. Inset shows a tunnel that has been created from orifice of inferior vena cava to right atrium. minutes, with the longest single period being 30 minutes. The body and perfusate temperature were 25° C. during the procedure. Cardiac action was satisfactory as bypass was discontinued. Pressures (in millimeters of mercury) after discontinuing bypass were as follows: right ventricle 45/5, left ventricle 75/5, aorta 80/50, right atrium 20/15, and left atrium 22/15. Heart block was present after repair, but sinus rhythm returned permanently during transfer to the intensive care unit. Although the cardiovascular system functioned excellently throughout, convalescence was seriously complicated by progressive hepatic failure of indefinite cause. Advanced, chronic, passive congestion of the liver had been present for an extended period preoperatively. The total bilirubin level increased relentlessly and progressively to reach 30 mg. per deciliter by 4 weeks postoperatively, despite intensive management. Even with this challenge, cardiac compensation was satisfactory. Finally, renal failure prevailed (hepatorenal syndrome), and death occurred from hemorrhage of esophageal varices on the thirtieth postoperative day. Postmortem examination showed that the cardiac repair was intact and satisfactory in all respects.
Transposition of the great arteries, severe pulmonary stenosis, and intact ventricular septum When pulmonary stenosis is severe, its relief at operation is seldom adequate, and thus repair by intra-atrial transposition of the venous return (Mustard
operation) is not an acceptable method. In such a situation, two approaches are possible. One is insertion of biventricular extracardiac conduits: one conduit from the right ventricle to the distal end of the divided pulmonary trunk and the other conduit from the left ventricle to the side of the ascending aorta, similar to that done in the operation described in Case 2. Our group has not yet had an opportunity to apply this concept to this anomaly. The second approach is illustrated by the following case. CASE 3 . A 6-year-old boy had transposition of the great arteries, severe subvalvular pulmonary stenosis, and moderate-to-severe mitral regurgitation. During infancy, he had undergone a right thoracotomy for creation of an atrial septal defect. When he was 20 months old, a left thoracotomy had been done for creation of an end-to-side left BlalockTaussig anastomosis. The severity of the subpulmonary stenosis apparently progressed until, at recent catheterization, most of the pulmonary blood flow was supplied by the Blalock-Taussig shunt and the left ventricular pressure had become greater than the systemic. The atrial pressures were elevated (18/11 mm. Hg) by moderate-to-severe mitral regurgitation, as documented by left ventriculogram. The boy was moderately cyanotic and limited in exercise tolerance, and he had a mild left hemiparesis from an event occurring during infancy. In November, 1975, operation revealed significant mitral regurgitation that dissuaded us from selecting the biventricu-
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Fig. 5. A composite septal patch has been inserted to which is attached (on its right and left surfaces) bioprosthetic mitral and tricuspid (Hancock) valves. Patch has been attached to edge of the inferior vena cava tunnel, completing the reconstruction of the inferior vena cava flow pathway. Dacron shunt has been removed, and large stoma has been established in the pulmonary artery. Pulmonary artery is not ligated or divided since it originates from the right ventricle. lar conduit approach, because the mitral valve would then function as the systemic atrioventricular valve and would surely require replacement. However, if the mitral valve were allowed to function as the pulmonary (low pressure) atrioventricular valve and if left ventricular systolic pressure were reduced from suprasystemic to nearly normal levels for the pulmonary ventricle by insertion of a left ventricle-topulmonary artery extracardiac conduit, it seemed likely that mitral function would be adequate. At operation, cannulas were inserted directly into each vena cava. After profound hypothermia (23° C.) had been established, the left pulmonary artery was incised longitudinally and the subclavian anastomosis was sutured closed from within the pulmonary artery during a 5 minute period of total circulatory arrest. Thereafter, four intervals of aortic crossclamping were employed, lasting from 6 to 20 minutes each, and at a perfusate temperature of 28° C. A very large atrial septal defect was further enlarged. The mitral valve was noted to be deformed because of thickening and retraction of both leaflets. Its annulus was not dilated, and no mitral repair was attempted. A standard Mustard operation was performed, and elastic knitted Teflon was used as the baffle material. Next, the incision in the left pulmonary artery was extended proximally to the base of the pulmonary trunk; to this, a 22 mm. Hancock conduit was anastomosed. Finally, a longitudinal incision was extended from the apex of the left ventricle
Surgery
Fig. 6. Conduits have been established from left and right ventricles to aorta and pulmonary artery, respectively. Aortic valve remains closed throughout cardiac cycle since aortic pressure is continuously higher than right ventricular pressure throughout cardiac cycle. 3.5 cm. toward the base of the heart and about 12 mm. lateral to the left anterior descending coronary artery. The left ventricle was hypertrophied and its cavity was small, but no muscle was excised along the ventriculotomy. The proximal end of the conduit was anastomosed to the margins of the ventriculotomy. Perfusion lasted 156 minutes, but hemodynamics were excellent immediately afterward. Pressures (millimeters of mercury) were as follows: right ventricle 105/5, left ventricle 45/5, right pulmonary artery 20/14, and "new" left atrium 14/9; there were no caval-to-atrial gradients. A normal sinus rhythm persisted postoperatively. Recovery was uneventful. The boy was extubated 16 hours after operation. An elective postoperative control catheterization was performed 1 week after operation. There was no gradient between the superior or inferior vena cava and the atrium just above the mitral valve. The wedge pressure was 16/9 mm. Hg, right pulmonary artery pressure 24/10, conduit pressure 28/10, and left ventricular pressure 32/6 mm. Hg. The cardiac index was 2.5 L. per minute per square meter, and the femoral arterial oxygen saturation was 91 per cent. The results of a left ventriculogram were also excellent (Fig. 7). The boy was dismissed from the hospital on the eleventh postoperative day. Discussion It is natural that widespread success resulting from insertion of a conduit from the right ventricle to the pulmonary artery should lead to consideration of
Volume 72 Number 1 July, 1976
insertion of a conduit from the left ventricle to the aorta or to the pulmonary artery. Four situations are described in this report in which compelling reasons exist to indicate that such a repair might be superior to other possible approaches. In the presence of isolated hypoplasia of the left ventricular outflow tract, operative enlargement of the outflow tract itself could be attempted by extending an aortotomy through the aortic annulus posteriorly into the anterior leaflet of the mitral valve, then inserting a gusset in the extended aortotomy and inserting a prosthetic valve in the aortic annulus. Similarly, the aortotomy could be extended anteriorly into the ventricular septum to communicate with the right ventricle, followed by similar insertion of a gusset and prosthetic valve (Konno17 operation). However, such radical manipulation within the heart, involving such important structures as the mitral mechanism or the ventricular septum, might be less well tolerated than a principally "extracardiac" procedure such as insertion of a conduit. 18-20 This contention is dependent on the durability of the valved conduit. Similarly, stenosis of the inverted left ventricular outflow tract (pulmonary stenosis) may be relieved less satisfactorily than the usual pulmonary stenosis. There are two reasons for this. First, patch graft reconstruction (gusset) of the inverted left ventricular outflow is not feasible because of adjacent major coronary arteries and the posterior position of the pulmonary annulus. Second, the bundle of His courses transversely near the anterior aspect of the pulmonary annulus21' 22 and would be injured by resection and reconstruction there. The classic type of double-outlet right ventricle is usually suitably corrected by constructing an intracardiac tunnel, which directs left ventricular outflow through the ventricular septal defect to the aorta via the tunnel.23 However, if the ventricular septal defect is subpulmonary rather than subaortic (Taussig-Bing anomaly), the classic repair is not suitable. Rather, in the past, either of two approaches has been used: (1) The ventricular septal defect has been closed so as to establish typical transposition of the great arteries (when the pulmonary artery is to the left and anterior), after which the Mustard repair24 has been done; (2) an elaborate intraventricular baffle has been required when the pulmonary artery is to the right and posterior.25 In such instances, external conduit repair may now be preferable. Repair of double-outlet right ventricle of the classic variety has not been adequately successful when the characteristics of the ventricular septal defect have been adverse. Thus, the risk in patients with an atrioventricular canal type of ventricular septal defect is excessive, 26-28 and in no patient with complete atrioventricu-
Extracardiac conduits
13
Fig. 7. Anteroposterior view after injection of contrast medium into left ventricle. Dual outlets of left ventricle are seen—the natural one being severely stenotic and the extracardiac conduit showing uniformity of caliber and a smooth contour. Note complete absence of mitral regurgitation, which had been moderately severe before operation. lar canal associated with double-outlet right ventricle has correction previously been successful.28 The use of double conduits, as recorded herein, provides a fresh and, hopefully, a more acceptable approach. Transposition of the great arteries with intact ventricular septum can be hemodynamically corrected by performing intra-atrial transposition of venous return (such as the Mustard24 operation). Recently, the hope for an anatomic correction has been stimulated by the success of Jatene and associates.29 When a ventricular septal defect is also present, three choices exist. The ventricular septal defect could be closed and either the Mustard or the Jatene procedure done, or an intracardiac tunnel could be fashioned from the ventricular septal defect to the aorta and a conduit attached from the right ventricle to the distal end of the divided pulmonary artery (Rastelli4 operation); the latter is especially appropriate when pulmonary stenosis is also present. However, the patient with intact ventricular septum and associated severe pulmonary stenosis has posed a particular problem because, if the stenosis could not be well relieved directly, the Mustard or Jatene approaches are not satisfactory; nor would the Rastelli operation be applicable unless a portion of the ventricular septum were excised and a ventricular septal defect thus created, which in limited experience has not given encouragement. A new anatomic solution to this problem, appropriate for consideration now, is the double conduit technique, whereby the right ventricle drains via its conduit to the distal end of the divided pulmonary trunk, and the left
14
The Journal of Thoracic and Cardiovascular Surgery
McGoon
ventricle, via a parallel conduit, to the aorta. The other solution, though less anatomic because the right ventricle remains the systemic ventricle, is illustrated herein and involves a combined Mustard technique and a conduit from the left ventricle to the pulmonary artery.
REFERENCES
1 Rastelli, G. C , Ongley, P. A., Davis, G. D., and Kirklin, J. W.: Surgical Repair for Pulmonary Valve Atresia With Coronary-Pulmonary Artery Fistula: Report of Case, Mayo Clin. Proc. 40: 521, 1965. 2 Ross, D. N., and Somerville, J.: Correction of Pulmonary Atresia With a Homograft Aortic Valve, Lancet 2: 1446, 1966. 3 McGoon, D. C , Rastelli, G. C , and Ongley, P. A.: An Operation for the Correction of Truncus Arteriosus, J. A. M. A. 205: 69, 1968. 4 Rastelli, G. C : A New Approach to "Anatomic" Repair of Transposition of the Great Arteries, Mayo Clin. Proc. 44: 1, 1969. 5 Rastelli, G. C , Wallace, R. B., and Ongley, P. A.: Complete Repair of Transposition of the Great Arteries With Pulmonary Stenosis: A Review and Report of a Case Corrected by Using a New Surgical Technique, Circulation 39: 83, 1969. 6 McGoon, D. C , Wallace, R. B., and Danielson, G. K.: Transposition With Ventricular Septal Defect and Pulmonary Stenosis: The Rastelli Operation, Isr. J. Med. Sci. 11: 82, 1975. 7 Marcelletti, C , McGoon, D. C , Danielson, G. K., Wallace, R. B., and Mair, D. D.: Early and Late Results of Surgical Repair of Truncus Arteriosus. Submitted for publication. 8 Olin, C. L., Ritter, D. G., McGoon, D. C , Wallace, R. B., and Danielson, G. K.: Pulmonary Atresia: Results in 103 Patients Undergoing Definitive Repair, Circulation. In press. 9 Gerbode, F., Kerth, W. J., Robinson, S., Ogata, T., and Popper, R.: Congenital Aortic Stenosis, Arch. Surg. 85: 10, 1962. 10 Kiser, J. C , Ongley, P. A., Kirklin, J. W., Clarkson, P. M., and McGoon, D. C : Surgical Treatment of Dextrocardia With Inversion of Ventricles and DoubleOutlet Right Ventricle, J. THORAC. CARDIOVASC. SURG.
55: 6, 1968. 11 McGoon, D. C , Pestana, C , and Moffitt, E. A.: Decreased Risk of Aortic Valve Surgery, Arch. Surg. 91: 779, 1965. 12 Rastelli, G. C , Ongley, P. A., Kirklin, J. W., and McGoon, D. C : Surgical Repair of the Complete Form of Persistent Common Atrioventricular Canal, J. THORAC. CARDIOVASC. SURG. 55: 299,
1968.
13 McMullan, M. H., Wallace, R. B., Weidman, W. H., and McGoon, D. C : Surgical Treatment of Complete Atrioventricular Canal, Surgery 72: 905, 1972.
14 Damus, P. S.: Personal communication. 15 Kaye, M. P.: Anatomic Correction of Transposition of Great Arteries, Mayo Clin. Proc. 50: 638, 1975. 16 Stansel, H. C , Jr.: A New Operation for rf-Loop Transposition of the Great Vessels, Ann. Thorac. Surg. 19: 565, 1975. 17 Konno, S., Imai, Y., Iida, Y., Nakajima, M., and Tatsuno, K.: A New Method for Prosthetic Valve Replacement in Congenital Aortic Stenosis Associated With Hypoplasia of the Aortic Valve Ring, J. THORAC. CARDIOVASC. SURG. 70: 909,
1975.
18 Sarnoff, S. J., Donovan, T. J., and Case, R. B.: The Surgical Relief of Aortic Stenosis by Means of ApicalAortic Valvular Anastomosis, Circulation 11: 564, 1955. 19 Brown, J. W., Myerowitz, P. D., Cann, M. S., Mclntosh, C. L., and Morrow, A. G.: Apical-Aortic Anastomosis: A Method for Relief of Diffuse Left Ventricular Outflow Obstruction, Surg. Forum 25: 147, 1974. 20 Bernhard, W. F., Poirier, V., and LaFarge, C. G.: Relief of Congenital Obstruction to Left Ventricular Outflow With a Ventricular-Aortic Prosthesis, J. THORAC. CARDIOVASC. SURG. 69: 223,
1975.
21 Lev, M., Licata, R. H., and May, R. C : The Conduction System in Mixed Levocardia With Ventricular Inversion (Corrected Transposition), Circulation 28: 232, 1963. 22 Anderson, R. H., Arnold, R., and Wilkinson, J. L.: The Conducting System in Congenitally Corrected Transposition, Lancet 1: 1286, 1973. 23 Kirklin, J. W., Harp, R. A., and McGoon, D. C : Surgical Treatment of Origin of Both Vessels From the Right Ventricle, Including Cases of Pulmonary Stenosis, J. THORAC. CARDIOVASC SURG. 48: 1026,
1964.
24 Mustard, W. T.: Successful Two-Stage Correction of Transposition of the Great Vessels, Surgery 55: 469, 1964. 25 Patrick, D. L., and McGoon, D. C : An Operation for Double-Outlet Right Ventricle With Transposition of the Great Arteries, J. Cardiovasc. Surg. (Torino) 9: 537, 1968. 26 Gomes, M. M. R., Weidman, W. H., McGoon, D. C , and Danielson, G. K.: Double-Outlet Right Ventricle Without Pulmonic Stenosis: Surgical Considerations and Results of Operation, Circulation 43: 31, 1971 (Suppl. I). 27 Gomes, M. M. R., Weidman, W. H., McGoon, D. C , and Danielson, G. K.: Double-Outlet Right Ventricle With Pulmonary Stenosis: Surgical Considerations and Results of Operation, Circulation 43: 889, 1971. 28 Sridaromont, S., Feldt, R. H., Ritter, D. G., Davis, G. D., McGoon, D. C , and Edwards, J. E.: Double-Outlet Right Ventricle Associated With Persistent Common Atrioventricular Canal, Circulation 52: 933, 1975. 29 Jatene, A. D., Fontes, V. F., Paulista, P. P., de Souza, L. C. B., Neger, F., Galantier, M., and Souza, J. E. M. R.: Successful Anatomic Correction of Transposition of the Great Vessels: A Preliminary Report, Arq. Bras. Cardiol. 28, Aug., 1975.
Dwight C. McGoon, M.D., Rochester,
Minn.
.Louring the 1960's, the concept was developed of using a conduit to establish an outflow tract connecting the right ventricle to the pulmonary trunk or arteries. The technique was applied in correction of pulmonary atresia, 1,2 truncus arteriosus,3 and transposition of the great arteries associated with ventricular septal defect and pulmonary stenosis.4, 5 The current hospital mortality rate of five to ten per cent for operations involving a conduit from the right ventricle to the pulmonary artery, the favorable follow-up results for the limited periods available thus far,6~8 and the fact that alternative corrective techniques are not available for these and related conditions all establish this procedure securely in the armamentarium of the cardiac surgeon. This success justifies exploration for other conditions which presently may be inadequately managed surgically and for which a conduit provides an appealing approach. Attention is directed to the possibility of inserting a valved conduit from the left ventricle to the appropriate great artery. Four possibilities present themselves. Situations exist in which hypoplasia of the left ventricular outflow tract cannot be adequately relieved by conventional reconstructive or replacement techniques. This is true in congenital aortic stenosis asFrom the Mayo Clinic and Mayo Foundation, Rochester, Minn. 55901. Received for publication Jan. 16, 1976. Accepted for publication Feb. 17, 1976.
sociated with hypoplasia of the subvalvular and supravalvular zones and of the aortic annulus.9 It is also often true in pulmonary stenosis when transposition and ventricular inversion (corrected transposition) are pressent, a condition in which dextrocardia and doubleoutlet right ventricle are often associated.10 Other situations exist in which the aorta originates from the right ventricle but in which an intracardiac repair is not feasible for directing left ventricular output to the aorta because of the absence of a ventricular septal defect or an inappropriately situated ventricular septal defect. This is true in certain types of double-outlet right ventricle, for example, those cases associated with complete atrioventricular canal (a combination not previously successfully corrected), and in transposition of the great arteries with intact ventricular septum, especially when associated severe pulmonary stenosis mitigates against the Mustard operation alone. A possible repair applicable in these last two situations involves insertion of twin conduits, one from the right ventricle to the pulmonary artery and one from the left ventricle to the aorta. Cases that illustrate the application of these four approaches are presented. Congenital aortic stenosis associated with hypoplasia of subvalvular and supravalvular zones and of the aortic annulus CASE 1. The boy was 7 years old at the time of his operation at the Mayo Clinic. He had had evidence of congenital aortic stenosis and coarctation since the age of 3 7
8
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McGoon
Fig. 1. Case I. A, Intraoperative appearance of conduit passing from apex of left ventricle (right upper end of conduit) to ascending aorta (anastomosis to aorta not seen in left lower corner). Valve-bearing segment of conduit can be identified in the center. B, Postoperative roentgenogram of chest taken at hospital dismissal. Table I. Serial cardiac catheterizations in patient with congenital aortic stenosis associated hypoplasia of subvalvular and supravalvular zones and of the aortic annulus First operation (age 6 yr.)
LVP (mm. Hg) Ascending aorta pressure (mm. Hg) Peak systolic LV-aortic gradient (mm. Hg) Cardiac index (L./min./sq. M.)
with
Second operation (age 7 yr.)
At age 3 yr.
At age 6 yr.
Intraoperative, after repair
Preop.
Intraoperative, before repair
Intraoperative, after repair
LV not entered
-
-
218/10
200/0
90/15
-
-
-
99/59
110/65
80/45
-
135
65
119
90
10
-
-
-
4.6
-
-
Legend: LVP, Left ventricular pressure. LV, Left ventricle.
years. Easy fatigability and shortness of breath on exertion were his significant symptoms. Open-heart surgery had been performed elsewhere 1 year previously, at which time the hypoplastic left ventricular outflow tract was noted, and maximal relief had been obtained by incising both commissures of the bicuspid aortic valve. The child continued to tire easily and to have shortness of breath on exertion. Data from the serial cardiac catheterizations are given in Table I. Credit must be given the boy's cardiologist, Dr. Gilbert H. Blount, who, in recommending reoperation, indicated the possible appropriateness of the "Rastelli approach." In July, 1975, at the Mayo Clinic, aortotomy confirmed the presence of a hypoplastic left ventricular outflow tract, which was narrowest at the level of the aortic annulus. The separation of the two cusps was already complete to the
annulus. A 10 mm. Hegar dilator fit snugly in the annulus. No discrete subvalvular constriction was present. Both coronary arteries were cannulated, and the myocardium was perfused continuously. The apex of the left ventricle was elevated, the apical vent was removed, and a ventriculotomy was extended 5 cm. cephalad from the apical vent site, parallel to (and 1.5 cm. lateral to) the left anterior descending artery. The base of the anterior papillary muscle of the mitral valve could be seen just lateral to the cephalad extent of the ventriculotomy. The endocardial edge of the ventriculotomy was trimmed on both sides. A 25 mm. diameter Dacron conduit containing a porcine valve* was cut on a wide angle and anastomosed to the margins of the ventriculotomy. The distal end of the *Hancock Laboratories, Inc., Anaheim, Calif.
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Extracardiac
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-Infundibular chamber
Fig. 2. Diagram of repair of levotransposition of great arteries with ventricular inversion, ventricular septal defect, and pulmonary stenosis. Conduit has been inserted from anatomic left ventricle to pulmonary artery. This illustration was utilized in an earlier report of an operation performed by Kirklin more than a decade ago. (From Kiser, J. C , Ongley, P. A., Kirklin, J. W., Clarkson, P. M , and McGoon, D. C : Surgical Treatment of Dextrocardia With Inversion of Ventricles and Double-Outlet Right Ventricle, J. THORAC. CARDIOVASC. SURG. 55: 6, 1968, published by The C. V. Mosby Company.) conduit was appropriately trimmed obliquely and anastomosed to the aortotomy. Air was evacuated, and coronary cannulas were withdrawn as for any aortic valve procedure," except that a needle was also inserted in the uppermost point of the conduit to ensure against air entrapment there. Cardiac action and hemodynamics seemed excellent immediately. The left lateral portion of the pericardium was incised longitudinally to allow the conduit to bulge into the left pleural space (Fig. 1, A). Extracorporeal circulation lasted 107 minutes. The boy's postoperative course was uneventful, and he was dismissed to his home on the sixteenth postoperative day, receiving no medications. A Grade 1/6 systolic murmur was present over the right upper sternal border. A chest roentgenogram obtained just before hospital dismissal is shown in Fig. 1, B. The referring cardiologist reported continued satisfactory progress 6 weeks postoperatively. Consideration will be given in the future to repair of the typical coarctation. Pulmonary stenosis, transposition arteries, and ventricular inversion
of the
great
The technique of choice at our institution for the : correction of most hearts with this anomaly has for
several years involved the insertion of a conduit from the morphologic left ventricle (right-sided pulmonary ventricle). This approach was first employed many years ago at the Mayo Clinic by Kirklin, undoubtedly the first instance in which a conduit from the left ventricle was inserted. This case was reported in 1968, 10 and the illustration from that report, reproduced herein (Fig. 2), still suffices to illustrate the technique. A study of the late result of the series of patients treated in this manner is in progress. Double-outlet right ventricle, pulmonary stenosis, anterior aorta, complete atrioventricular canal, rudimentary AV valve leaflets, anomalous systemic venous connection, situs inversus dextrocardia, left Blalock-Taussig anastomosis, and asplenia CASE 2. The boy was 14 years old at the time of his corrective operation. He had been cyanotic since infancy. He underwent cardiac catheterization at the Mayo Clinic at the age of 5 months and again at the age of 5 years. Data at operation provided the diagnosis of situs inversus, doubleoutlet right ventricle, pulmonary stenosis, ventricular septal
10
McGoon
Fig. 3. Case 2. Anatomic detail. The interior of morphologic right ventricle and right atrium. Atrioventricular valves have not been drawn in order to simplify the anatomy. Large central septal defect of complete atrioventricular canal is shown, along with double-outlet right ventricle, pulmonary stenosis, inferior vena cava to left atrium, bilateral superior venae cavae, one to each atrium, left Blalock-Taussig anastomosis, Dacron shunt from ascending aorta to pulmonary artery, and situs inversus totalis. defect, and atrial septal defect, as well as bilateral superior venae cavae. Because of increasingly severe cyanosis (hemoglobin level 18.8 Gm. per deciliter), a highly successful left Blalock-Taussig anastomosis was performed at the Mayo Clinic by Dr. John Kirklin when the patient was 5 years old. The complexity of the cardiac malformation dissuaded an attempt at complete repair for some years, but it was finally undertaken when he was 13 years old (1 year before actual correction). On this occasion, I found an associated complete atrioventricular canal deformity, as well as the anomalous connection of the inferior vena cava with the morphologic left atrium, by palpation within the heart. The presence of double-outlet right ventricle with the aorta anterior as well as pulmonary stenosis was confirmed. Previous attempts at repair of associated complete atrioventricular canal and double-oudet right ventricle had been unsuccessful. This lack of success, combined with the presence of the other associated anomalies and the possibility that further palliation could be achieved by a supplemental shunt procedure, led us to avoid establishing extracorporeal circulation. A Dacron arterial prosthesis was anastomosed between the ascending aorta and the left pulmonary artery. Unfortunately, palliation was not realized. During the
The Journal of Thoracic and Cardiovascular Surgery
subsequent year, progressively severe congestive heart failure, anasarca, cardiomegaly, and cardiac cachexia developed, primarily because of progressive regurgitation at the atrioventricular valve. In August, 1975, heart-lung bypass was instituted by cannulating the right external iliac artery and the left superior and inferior venae cavae via the right atrium.* The inferior cava penetrated the central area of the diaphragm and entered the left atrium directly in the midline (Fig. 3). The right superior vena cava was ligated, which resulted in no increment in right jugular venous pressure. The left subclavian artery was ligated, and the chronically occluded Dacron graft was disengaged from the aorta, later to be removed. A wide atriotomy was created. The presence of a complete atrioventricular canal deformity was confirmed, and a rudimentary atrioventricular valve leaflet, which did not conform to any of the classic types,12 was excised. A 16 mm. knitted Dacron arterial prosthesis was opened longitudinally and sutured about the inferior caval orifice and along the posterior aspect of the left atrium, so as to create a tunnel extending the inferior cava to the right atrium (Fig. 4). A composite prosthesis was fashioned, consisting of a large oval patch of intracardiac knitted Teflon and 27 mm. Hancock frame-mounted porcine valves sutured at slightly different levels on each side of the patch about 1.5 cm. above its lower (ventricular) rim (Fig. 5). This patch was first attached to the crest of the ventricular septum by use of interrupted silk sutures, as in the standard repair of complete atrioventricular canal.13 Next, the edges of the left and right Hancock valve frames, which were not attached to the patch, were sutured to the annuli of the mitral and tricuspid valves, respectively and sequentially. Next, the atrial edge of the septal patch was sutured to the rim of the atrial septum (except at the inferior caval tunnel, to which the septal patch was sutured). The intracardiac portion of the repair was then complete (Fig. 5), and the atriotomy site was closed. The left pulmonary artery was incised longitudinally from the left superior vena cava proximally to the origin of the pulmonary trunk. A 25 mm. Hancock conduit was anastomosed to this incision. A partial-occlusion clamp was applied to the anterior aspect of the ascending aorta, and a 3 cm. incision was made in the aorta, to which an obliquely cut, second Hancock conduit (also 25 mm. in diameter) was anastomosed. A left ventriculotomy was made in the manner described for Case 1, and the proximal end of the aortic conduit was anastomosed to it. Finally, a longitudinal right ventriculotomy was made, and the pulmonary conduit was anastomosed to it (Fig. 6). Flow into the aorta from the left ventricle via the conduit thus has access to the coronary arteries proximally as well as the distal aorta. Because the intra-aortic pressure is greater throughout the cardiac cycle than right ventricular pressure, the aortic valve remains closed at all times. This is an application of the concept developed independently by Damus,14 Kaye,15 and Stansel.16 Cardiopulmonary bypass lasted 250 minutes, and the aorta was cross-clamped on multiple occasions, totaling 76 *In this description, the laterality of the cavae and pulmonary arteries is indicated in accordance with their positions in the body, but the atria and ventricles, which are each in situs inversus, are named in accordance with their morphology.
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Extracardiac
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Fig. 4. Case 2. Anterior portion of heart has not been drawn in order to show both ventricles. Blalock-Taussig anastomosis has been ligated, as has right superior vena cava, and Dacron shunt has been divided. Inset shows a tunnel that has been created from orifice of inferior vena cava to right atrium. minutes, with the longest single period being 30 minutes. The body and perfusate temperature were 25° C. during the procedure. Cardiac action was satisfactory as bypass was discontinued. Pressures (in millimeters of mercury) after discontinuing bypass were as follows: right ventricle 45/5, left ventricle 75/5, aorta 80/50, right atrium 20/15, and left atrium 22/15. Heart block was present after repair, but sinus rhythm returned permanently during transfer to the intensive care unit. Although the cardiovascular system functioned excellently throughout, convalescence was seriously complicated by progressive hepatic failure of indefinite cause. Advanced, chronic, passive congestion of the liver had been present for an extended period preoperatively. The total bilirubin level increased relentlessly and progressively to reach 30 mg. per deciliter by 4 weeks postoperatively, despite intensive management. Even with this challenge, cardiac compensation was satisfactory. Finally, renal failure prevailed (hepatorenal syndrome), and death occurred from hemorrhage of esophageal varices on the thirtieth postoperative day. Postmortem examination showed that the cardiac repair was intact and satisfactory in all respects.
Transposition of the great arteries, severe pulmonary stenosis, and intact ventricular septum When pulmonary stenosis is severe, its relief at operation is seldom adequate, and thus repair by intra-atrial transposition of the venous return (Mustard
operation) is not an acceptable method. In such a situation, two approaches are possible. One is insertion of biventricular extracardiac conduits: one conduit from the right ventricle to the distal end of the divided pulmonary trunk and the other conduit from the left ventricle to the side of the ascending aorta, similar to that done in the operation described in Case 2. Our group has not yet had an opportunity to apply this concept to this anomaly. The second approach is illustrated by the following case. CASE 3 . A 6-year-old boy had transposition of the great arteries, severe subvalvular pulmonary stenosis, and moderate-to-severe mitral regurgitation. During infancy, he had undergone a right thoracotomy for creation of an atrial septal defect. When he was 20 months old, a left thoracotomy had been done for creation of an end-to-side left BlalockTaussig anastomosis. The severity of the subpulmonary stenosis apparently progressed until, at recent catheterization, most of the pulmonary blood flow was supplied by the Blalock-Taussig shunt and the left ventricular pressure had become greater than the systemic. The atrial pressures were elevated (18/11 mm. Hg) by moderate-to-severe mitral regurgitation, as documented by left ventriculogram. The boy was moderately cyanotic and limited in exercise tolerance, and he had a mild left hemiparesis from an event occurring during infancy. In November, 1975, operation revealed significant mitral regurgitation that dissuaded us from selecting the biventricu-
The Journal of
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Thoracic and Cardiovascular
McGoon
Fig. 5. A composite septal patch has been inserted to which is attached (on its right and left surfaces) bioprosthetic mitral and tricuspid (Hancock) valves. Patch has been attached to edge of the inferior vena cava tunnel, completing the reconstruction of the inferior vena cava flow pathway. Dacron shunt has been removed, and large stoma has been established in the pulmonary artery. Pulmonary artery is not ligated or divided since it originates from the right ventricle. lar conduit approach, because the mitral valve would then function as the systemic atrioventricular valve and would surely require replacement. However, if the mitral valve were allowed to function as the pulmonary (low pressure) atrioventricular valve and if left ventricular systolic pressure were reduced from suprasystemic to nearly normal levels for the pulmonary ventricle by insertion of a left ventricle-topulmonary artery extracardiac conduit, it seemed likely that mitral function would be adequate. At operation, cannulas were inserted directly into each vena cava. After profound hypothermia (23° C.) had been established, the left pulmonary artery was incised longitudinally and the subclavian anastomosis was sutured closed from within the pulmonary artery during a 5 minute period of total circulatory arrest. Thereafter, four intervals of aortic crossclamping were employed, lasting from 6 to 20 minutes each, and at a perfusate temperature of 28° C. A very large atrial septal defect was further enlarged. The mitral valve was noted to be deformed because of thickening and retraction of both leaflets. Its annulus was not dilated, and no mitral repair was attempted. A standard Mustard operation was performed, and elastic knitted Teflon was used as the baffle material. Next, the incision in the left pulmonary artery was extended proximally to the base of the pulmonary trunk; to this, a 22 mm. Hancock conduit was anastomosed. Finally, a longitudinal incision was extended from the apex of the left ventricle
Surgery
Fig. 6. Conduits have been established from left and right ventricles to aorta and pulmonary artery, respectively. Aortic valve remains closed throughout cardiac cycle since aortic pressure is continuously higher than right ventricular pressure throughout cardiac cycle. 3.5 cm. toward the base of the heart and about 12 mm. lateral to the left anterior descending coronary artery. The left ventricle was hypertrophied and its cavity was small, but no muscle was excised along the ventriculotomy. The proximal end of the conduit was anastomosed to the margins of the ventriculotomy. Perfusion lasted 156 minutes, but hemodynamics were excellent immediately afterward. Pressures (millimeters of mercury) were as follows: right ventricle 105/5, left ventricle 45/5, right pulmonary artery 20/14, and "new" left atrium 14/9; there were no caval-to-atrial gradients. A normal sinus rhythm persisted postoperatively. Recovery was uneventful. The boy was extubated 16 hours after operation. An elective postoperative control catheterization was performed 1 week after operation. There was no gradient between the superior or inferior vena cava and the atrium just above the mitral valve. The wedge pressure was 16/9 mm. Hg, right pulmonary artery pressure 24/10, conduit pressure 28/10, and left ventricular pressure 32/6 mm. Hg. The cardiac index was 2.5 L. per minute per square meter, and the femoral arterial oxygen saturation was 91 per cent. The results of a left ventriculogram were also excellent (Fig. 7). The boy was dismissed from the hospital on the eleventh postoperative day. Discussion It is natural that widespread success resulting from insertion of a conduit from the right ventricle to the pulmonary artery should lead to consideration of
Volume 72 Number 1 July, 1976
insertion of a conduit from the left ventricle to the aorta or to the pulmonary artery. Four situations are described in this report in which compelling reasons exist to indicate that such a repair might be superior to other possible approaches. In the presence of isolated hypoplasia of the left ventricular outflow tract, operative enlargement of the outflow tract itself could be attempted by extending an aortotomy through the aortic annulus posteriorly into the anterior leaflet of the mitral valve, then inserting a gusset in the extended aortotomy and inserting a prosthetic valve in the aortic annulus. Similarly, the aortotomy could be extended anteriorly into the ventricular septum to communicate with the right ventricle, followed by similar insertion of a gusset and prosthetic valve (Konno17 operation). However, such radical manipulation within the heart, involving such important structures as the mitral mechanism or the ventricular septum, might be less well tolerated than a principally "extracardiac" procedure such as insertion of a conduit. 18-20 This contention is dependent on the durability of the valved conduit. Similarly, stenosis of the inverted left ventricular outflow tract (pulmonary stenosis) may be relieved less satisfactorily than the usual pulmonary stenosis. There are two reasons for this. First, patch graft reconstruction (gusset) of the inverted left ventricular outflow is not feasible because of adjacent major coronary arteries and the posterior position of the pulmonary annulus. Second, the bundle of His courses transversely near the anterior aspect of the pulmonary annulus21' 22 and would be injured by resection and reconstruction there. The classic type of double-outlet right ventricle is usually suitably corrected by constructing an intracardiac tunnel, which directs left ventricular outflow through the ventricular septal defect to the aorta via the tunnel.23 However, if the ventricular septal defect is subpulmonary rather than subaortic (Taussig-Bing anomaly), the classic repair is not suitable. Rather, in the past, either of two approaches has been used: (1) The ventricular septal defect has been closed so as to establish typical transposition of the great arteries (when the pulmonary artery is to the left and anterior), after which the Mustard repair24 has been done; (2) an elaborate intraventricular baffle has been required when the pulmonary artery is to the right and posterior.25 In such instances, external conduit repair may now be preferable. Repair of double-outlet right ventricle of the classic variety has not been adequately successful when the characteristics of the ventricular septal defect have been adverse. Thus, the risk in patients with an atrioventricular canal type of ventricular septal defect is excessive, 26-28 and in no patient with complete atrioventricu-
Extracardiac conduits
13
Fig. 7. Anteroposterior view after injection of contrast medium into left ventricle. Dual outlets of left ventricle are seen—the natural one being severely stenotic and the extracardiac conduit showing uniformity of caliber and a smooth contour. Note complete absence of mitral regurgitation, which had been moderately severe before operation. lar canal associated with double-outlet right ventricle has correction previously been successful.28 The use of double conduits, as recorded herein, provides a fresh and, hopefully, a more acceptable approach. Transposition of the great arteries with intact ventricular septum can be hemodynamically corrected by performing intra-atrial transposition of venous return (such as the Mustard24 operation). Recently, the hope for an anatomic correction has been stimulated by the success of Jatene and associates.29 When a ventricular septal defect is also present, three choices exist. The ventricular septal defect could be closed and either the Mustard or the Jatene procedure done, or an intracardiac tunnel could be fashioned from the ventricular septal defect to the aorta and a conduit attached from the right ventricle to the distal end of the divided pulmonary artery (Rastelli4 operation); the latter is especially appropriate when pulmonary stenosis is also present. However, the patient with intact ventricular septum and associated severe pulmonary stenosis has posed a particular problem because, if the stenosis could not be well relieved directly, the Mustard or Jatene approaches are not satisfactory; nor would the Rastelli operation be applicable unless a portion of the ventricular septum were excised and a ventricular septal defect thus created, which in limited experience has not given encouragement. A new anatomic solution to this problem, appropriate for consideration now, is the double conduit technique, whereby the right ventricle drains via its conduit to the distal end of the divided pulmonary trunk, and the left
14
The Journal of Thoracic and Cardiovascular Surgery
McGoon
ventricle, via a parallel conduit, to the aorta. The other solution, though less anatomic because the right ventricle remains the systemic ventricle, is illustrated herein and involves a combined Mustard technique and a conduit from the left ventricle to the pulmonary artery.
REFERENCES
1 Rastelli, G. C , Ongley, P. A., Davis, G. D., and Kirklin, J. W.: Surgical Repair for Pulmonary Valve Atresia With Coronary-Pulmonary Artery Fistula: Report of Case, Mayo Clin. Proc. 40: 521, 1965. 2 Ross, D. N., and Somerville, J.: Correction of Pulmonary Atresia With a Homograft Aortic Valve, Lancet 2: 1446, 1966. 3 McGoon, D. C , Rastelli, G. C , and Ongley, P. A.: An Operation for the Correction of Truncus Arteriosus, J. A. M. A. 205: 69, 1968. 4 Rastelli, G. C : A New Approach to "Anatomic" Repair of Transposition of the Great Arteries, Mayo Clin. Proc. 44: 1, 1969. 5 Rastelli, G. C , Wallace, R. B., and Ongley, P. A.: Complete Repair of Transposition of the Great Arteries With Pulmonary Stenosis: A Review and Report of a Case Corrected by Using a New Surgical Technique, Circulation 39: 83, 1969. 6 McGoon, D. C , Wallace, R. B., and Danielson, G. K.: Transposition With Ventricular Septal Defect and Pulmonary Stenosis: The Rastelli Operation, Isr. J. Med. Sci. 11: 82, 1975. 7 Marcelletti, C , McGoon, D. C , Danielson, G. K., Wallace, R. B., and Mair, D. D.: Early and Late Results of Surgical Repair of Truncus Arteriosus. Submitted for publication. 8 Olin, C. L., Ritter, D. G., McGoon, D. C , Wallace, R. B., and Danielson, G. K.: Pulmonary Atresia: Results in 103 Patients Undergoing Definitive Repair, Circulation. In press. 9 Gerbode, F., Kerth, W. J., Robinson, S., Ogata, T., and Popper, R.: Congenital Aortic Stenosis, Arch. Surg. 85: 10, 1962. 10 Kiser, J. C , Ongley, P. A., Kirklin, J. W., Clarkson, P. M., and McGoon, D. C : Surgical Treatment of Dextrocardia With Inversion of Ventricles and DoubleOutlet Right Ventricle, J. THORAC. CARDIOVASC. SURG.
55: 6, 1968. 11 McGoon, D. C , Pestana, C , and Moffitt, E. A.: Decreased Risk of Aortic Valve Surgery, Arch. Surg. 91: 779, 1965. 12 Rastelli, G. C , Ongley, P. A., Kirklin, J. W., and McGoon, D. C : Surgical Repair of the Complete Form of Persistent Common Atrioventricular Canal, J. THORAC. CARDIOVASC. SURG. 55: 299,
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13 McMullan, M. H., Wallace, R. B., Weidman, W. H., and McGoon, D. C : Surgical Treatment of Complete Atrioventricular Canal, Surgery 72: 905, 1972.
14 Damus, P. S.: Personal communication. 15 Kaye, M. P.: Anatomic Correction of Transposition of Great Arteries, Mayo Clin. Proc. 50: 638, 1975. 16 Stansel, H. C , Jr.: A New Operation for rf-Loop Transposition of the Great Vessels, Ann. Thorac. Surg. 19: 565, 1975. 17 Konno, S., Imai, Y., Iida, Y., Nakajima, M., and Tatsuno, K.: A New Method for Prosthetic Valve Replacement in Congenital Aortic Stenosis Associated With Hypoplasia of the Aortic Valve Ring, J. THORAC. CARDIOVASC. SURG. 70: 909,
1975.
18 Sarnoff, S. J., Donovan, T. J., and Case, R. B.: The Surgical Relief of Aortic Stenosis by Means of ApicalAortic Valvular Anastomosis, Circulation 11: 564, 1955. 19 Brown, J. W., Myerowitz, P. D., Cann, M. S., Mclntosh, C. L., and Morrow, A. G.: Apical-Aortic Anastomosis: A Method for Relief of Diffuse Left Ventricular Outflow Obstruction, Surg. Forum 25: 147, 1974. 20 Bernhard, W. F., Poirier, V., and LaFarge, C. G.: Relief of Congenital Obstruction to Left Ventricular Outflow With a Ventricular-Aortic Prosthesis, J. THORAC. CARDIOVASC. SURG. 69: 223,
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21 Lev, M., Licata, R. H., and May, R. C : The Conduction System in Mixed Levocardia With Ventricular Inversion (Corrected Transposition), Circulation 28: 232, 1963. 22 Anderson, R. H., Arnold, R., and Wilkinson, J. L.: The Conducting System in Congenitally Corrected Transposition, Lancet 1: 1286, 1973. 23 Kirklin, J. W., Harp, R. A., and McGoon, D. C : Surgical Treatment of Origin of Both Vessels From the Right Ventricle, Including Cases of Pulmonary Stenosis, J. THORAC. CARDIOVASC SURG. 48: 1026,
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24 Mustard, W. T.: Successful Two-Stage Correction of Transposition of the Great Vessels, Surgery 55: 469, 1964. 25 Patrick, D. L., and McGoon, D. C : An Operation for Double-Outlet Right Ventricle With Transposition of the Great Arteries, J. Cardiovasc. Surg. (Torino) 9: 537, 1968. 26 Gomes, M. M. R., Weidman, W. H., McGoon, D. C , and Danielson, G. K.: Double-Outlet Right Ventricle Without Pulmonic Stenosis: Surgical Considerations and Results of Operation, Circulation 43: 31, 1971 (Suppl. I). 27 Gomes, M. M. R., Weidman, W. H., McGoon, D. C , and Danielson, G. K.: Double-Outlet Right Ventricle With Pulmonary Stenosis: Surgical Considerations and Results of Operation, Circulation 43: 889, 1971. 28 Sridaromont, S., Feldt, R. H., Ritter, D. G., Davis, G. D., McGoon, D. C , and Edwards, J. E.: Double-Outlet Right Ventricle Associated With Persistent Common Atrioventricular Canal, Circulation 52: 933, 1975. 29 Jatene, A. D., Fontes, V. F., Paulista, P. P., de Souza, L. C. B., Neger, F., Galantier, M., and Souza, J. E. M. R.: Successful Anatomic Correction of Transposition of the Great Vessels: A Preliminary Report, Arq. Bras. Cardiol. 28, Aug., 1975.