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Surgical Palliation of Single Ventricle with Pulmonary Stenosis
Surgical Palliation of Single Ventricle with Pulmonary Stenosis Michael P. Holden, M.D., Fergus J. Macartney, M.D., and Marian I. Ionescu, M.D. ABSTRACT Two patients aged 9 and 18 years underwent palliative correction of single ventricle with pulmonary stenosis by insertion of a fascia lata composite graft between the anterior aspect of the ventricle and the main pulmonary artery. Both patients had satisfactory hemodynamic states postoperatively, but 1 died of subarachnoid hemorrhage and the other from generalized infection. The surgical technique and the pathology as seen at operation and at postmortem examination are described. The potential merits of this type of palliation are discussed.
D
efinitive repair of single ventricle presents formidable technical problems. T o our knowledge there has been only one published report of intracardiac correction of single ventricle [4].The major difficulty is undoubtedly that of separating and appropriately directing the pulmonary and systemic venous return within the ventricle without compromising the conduction system or atrioventricular valve function, while at the same time creating two ventricular cavities whose functional capacity approaches that of the normal left and right ventricle. Another major problem is relieving the pulmonary outflow obstruction. I n patients without pulmonary stenosis, the high incidence of pulmonary vascular disease represents an additional hazard [7]. T h e experience in 2 patients of attempted palliation by relief of pulmonary stenosis, rather than by a shunt operation, is reported in the hope that it will contribute to the development of a procedure for radical correction of single ventricle with pulmonary stenosis. PATIENT 1
This patient had been cyanotic since birth on June 14, 1961. He had always been severely handicapped physically and at the. time of operation was unable to walk up more than a few stairs without severe dyspnea. On physical examination he was severely cyanotic with marked finger clubbing. From the Departments of Cardio-thoracic Surgery and Cardiology, The General Infirmary at Leeds and Killingbeck Hospital, and Leeds University School of Medicine, Leeds, England. Supported by the British Heart Foundation. The authors gratefully acknowledge the assistance of Mrs. Judith Ladley with this work. Accepted for publication Feb. 1, 1973. Address reprint requests to Mr. Ionescu, Department of Cardio-thoracic Surgery, The General Infirmary, Leeds, England.
578
THE ANNALS OF THORACIC SURGERY
Palliation of Single Ventricle
The arterial and venous pulses were normal. The first and second heart sounds were single, and there was a moderately loud ejection systolic murmur that was maximal in the pulmonary area. The electrocardiogram showed sinus rhythm with right atrial and right ventricular hypertrophy. The chest roentgenogram (Fig. 1) showed an enlarged heart with an uptilted apex and a left aortic arch. Neither the right atrium nor the pulmonary artery was prominent. An anomalous right upper pulmonary vein could be seen apparently entering the right atrium. The right lower pulmonary vein was grossly dilatated. The left lung field showed a coarsely reticular pattern consistent with collateral blood supply. There was also some linear atelectasis at the right base. An angiocardiogram (Fig. 2) performed in another hospital in 1962 showed that with the catheter through the “tricuspid” valve, contrast medium was injected into an enlarged, trabeculated right ventricular cavity giving rise to a transposed aorta lying above a well-defined subaortic conus. There was extreme subpulmonary stenosis, with the pulmonary valve lying slightly behind, to the left of, and at about the same horizontal level as the aortic valve. No second ventricular cavity was identified. The right upper pulmonary vein was seen to drain to the superior vena cava and the remaining pulmonary veins to the left atrium. The mitral valve was not clearly seen. On March 9, 1970, the heart was exposed through a median sternotomy. After exploration before and during perfusion, a diagnosis was made of mitral atresia with common ventricle, transposition of the great vessels, and pulmonary stenosis. The right upper pulmonary vein drained to the right superior vena cava, and the remaining pulmonary veins drained normally. However, the left atrium did not appear to communicate with either the right atrium or a ventricle. The pulmonary artery arose from a rudimentary FIG. 1 . Posteroanterior chest roentgenogram of Patient 1, showing the enlarged heart with an uplifted apex and left aortic arch. An anomalous right upper pulmonary vein apparently enters the right atrium. T h e right lower pulmonary vein is enlarged. T h e left lung field shows a coarsely reticular pattern consistent with collateral circulation. There is some linear atelectasis at the right base.
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FIG. 2. Preoperative angiocardiogram in Patient I, lateral view. W i t h the catheter through the “tricuspid” valve, contrast medium was injected into an enlarged, trabeculated right ventricular cavity (RV) from which a transposed aorta originates (AO). T h e pulmonary stenosis is indicated by an open arrow.
ventricular chamber communicating with the main (right) ventricular cavity through an 8 mm. aperture. Since no corrective operation was possible, the atrial septum was excised to relieve pulmonary venous obstruction, and a composite fascia lata graft (a valve-bearing conduit) was inserted between the rudimentary ventricular cavity and the bifurcation of the pulmonary artery. Cardiopulmonary bypass was discontinued without difficulty, but four hours after the operation the patient had a sudden cardiac arrest and could not be resuscitated. Pathological Findings. Postmortem examination showed that the immediate cause of death was a massive subarachnoid hemorrhage due to rupture of a congenital aneurysm of the circle of Willis. T h e heart (Fig. 3) weighed 150 gm. Systemic venous drainage was normal to an enlarged right atrium, which received the coronary sinus and contained the crista terminalis. The atria were in situs solitus, and the left atrium was small. T h e atretic mitral valve was represented by a dimple. T h e right upper pulmonary vein entered the superior vena cava about 4 cm. above its junction with the right atrium. T h e remaining pulmonary veins drained into the left atrium. Extensive intrapulmonary dissection of the pulmonary veins was not done. T h e atrial septum had been excised. From the right atrium an atrioventricular valve entered an enlarged ventricular chamber with coarsely trabeculated walls. This valve had four cusps and was not typical of a tricuspid valve in that there was no papillary muscle of the conus, but instead a large posteromedial cusp resembling the anterior cusp of a mitral valve. This atrioventricular valve cusp was separated from the aortic annulus by a small band of muscle. Through an 8 mm. aperture the right ventricle communicated with a rudimentary, centrally positioned anterior outflow
580
THE ANNALS OF THORACIC SURGERY
Palliation of Single Ventricle
chamber that gave origin to the pulmonary artery by way of an almost atretic outflow tract and valve. T h e aortic valve was located to the right and slightly anterior to the pulmonary valve. A fascia lata composite graft had been used to connect the rudimentary outflow chamber (which was in no way related to the left atrium) to the bifurcation of the pulmonary artery. T h e middle and lower lobes of the right lung were congested and edematous, as was the left lung.
A
B
FIG. 3. T h e heart from Patient 1. ( A ) Anterior view of the heart with the composite fascia lata graft inserted as a bypass from the rudimentary ventricle to the bifurcation of the pulmonary artery. ( B ) T h e interior of the heart with the right atrium widely opened. T h e left atrium is seen through the atrial septum removed at operation. T h e atrioventricular valve, containing four cusps, opens into a coarsely tmbeculated, large ventricular chamber. (CS = ostium of the coronary sinus.) ( C ) T h e interior of the heart with the ventricle opened. T h e atrioventricular valve (AV) is separated from the aortic valve (+) by a small band of muscle (white arrow) and by the atretic mitral valve ( M ) . T h e black arrow points toward the opening of the pulmonary artery. (CS = crista supraventricularis; *+ = rudimentary outflow chamber.)
C VOL.
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1973
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This patient, together with a normal twin brother, was born in 1952 after an uncomplicated pregnancy. She was cyanotic from birth and squatted frequently. At the time of operation when she was 18 years old, she could not walk more than 100 yards on the flat and was severely cyanotic with gross finger clubbing. Her arterial pulses were normal, but there was a 2 cm. “a” wave in the jugular venous pulse. There was a left parasternal heave, and the second heart sound was palpable. On auscultation the first heart sound was followed by an aortic ejection click. T h e second heart sound was single, and there was a moderately loud systolic ejection murmur in the pulmonary area. T h e chest roentgenogram (Fig. 4) was characteristic of corrected transposition with pulmonary stenosis, there being a narrow heart with oligemic lung fields and with the ascending aorta prominent on the left upper cardiac border. T h e electrocardiogram showed P pulmonale with a mean frontal QRS axis of +135 degrees. Small Q waves were present in leads 111, aVF, and V1, but not in the left precordial leads. Cardiac catheterization and angiocardiography performed in 1954 and April, 1970, had demonstrated corrected transposition of the great arteries with pulmonary stenosis. T h e exact ventricular anatomy was not clarified, though the possibility of common ventricle had been raised. On May 11, 1970, an operation was carried out under heart-lung bypass. On opening the heart it became apparent that there was a single ventricle with inversion of the infundibulum and severe pulmonary stenosis. T h e left atrioventricular valve annulus was hypoplastic, and for this reason in particular no attempt was made to create a ventricular septum. Instead, a FIG. 4 . Posteroanterior chest roentgenogram of Patient 2.
582
THE ANNALS OF THORACIC SURGERY
Palliation of Single Ventricle
composite fascia lata graft was inserted as a bypass between the ventricle and the pulmonary artery. Perfusion was terminated without difficulty. Tracheostomy was performed on the second postoperative day because of pulmonary dysfunction, and as this continued notwithstanding, on the third postoperative day the distal end of the graft tube was constricted with a Teflon band to reduce the distal systolic pressure from 40 to 20 mm. Hg. For the next three weeks cardiac output remained adequate as judged by cerebral, renal, and skin perfusion. Cyanosis was judged clinically to be less than it had been preoperatively. The arterial Po2 was 80 mm. Hg with the patient breathing 40% oxygen. During the third postoperative week the patient developed pyrexia. At the same time multiple stitch abscesses appeared in the median sternotomy wound; they grew a coagulase-negative Staphylococcus and subsequently Candida and coliform bacilli, which also appeared in the urine. Despite vigorous antibiotic treatment, the patient remained pyrexial and developed signs of intracranial infection. One month after the operation the patient developed peripheral edema and elevation of the jugular venous pressure that responded to diuretic therapy. She died six weeks after the operation with overwhelming infection. Pathological Findings. Postmortem examination showed inflammation of the pericardium with areas of mottling and petechial hemorrhages in the myocardium. There were diffuse petechial hemorrhages in the brain. The anatomy of the heart was typical of a single ventricle with inversion of the infundibulum (Fig. 5). Pulmonary and systemic venous returns were normal. The left atrium was rather small. Two atrioventricular valves that were in fibrous continuity entered a finely trabeculated common ventricle. The valve entering from the right atrium was tricuspid, whereas the valve from the left atrium was bicuspid with a valve annulus that would only admit the tip of a little finger. The pulmonary valve was bicuspid and severely stenotic, having a 1 mm. orifice. It was in tenuous continuity with the right atrioventricular valve. The aorta arose from a subaortic chamber lying anterior to, above, and to the left of the common ventricle. The aortic valve lay above, anterior to, and to the left of the pulmonary valve, and the ascending aorta took a course typical for corrected transposition. A composite fascia lata graft had been inserted between the site of the ventriculotomy and the bifurcation of the pulmonary artery. The pulmonary artery had been banded.
Comment Opinions differ on whether or not mitral atresia should be included in the category of single ventricle [2, 101. Mitral atresia presents even more formidable problems in surgical correction than does common ventricle with two patent atrioventricular valves, so there are good, practical reasons for
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HOLDEN, MACARTNEY, AND IONESCU
A
B FIG. 5. T h e heart from Patient 2. ( A } Anterolateral view of the heart. (RA=right atrium; A 0 = ascending aorta; FLG = fascia lata composite graft inserted as a bypass from the common ventricle to the bifurcation of the pulmonary artery.) T h e graft was banded at its distal end. ( B ) View of the atria. T h e atrial septum was removed in order to show both atrioventricular valves. T h e right atrium is considerably bigger than the left. (RAV = right atrioventricular valve [tricuspid]; LAV = left atrioventricular valve [bicuspid].)
584
THE ANNALS OF THORACIC SURGERY
Palliation of Single Ventricle
C FIG. 5 (Continued). ( C ) T h e interior of the heart with the ventricle and aorta opened. (TV = tricuspid valve; MV = mitral value; AV = aortic value; * = subaortic chamber.) T h e probe was passed through the pulmonary artery.
separating mitral atresia from single ventricle. However, since we are concerned here with the relief of pulmonary stenosis rather than the division of a common ventricle into two functioning cavities, the nomenclature of Eliot and Elliott and their associates [l, 21 has been adopted. Hemodynamically, single ventricle is characterized by bidirectional shunting of blood at the ventricular level. Mixing of systemic and pulmonary venous blood is not always complete [7], though it seems likely that the addition of mitral atresia increases mixing since it then occurs at the right atrial level as well. The degree of systemic desaturation in single ventricle is therefore dependent upon (1) streaming within the ventricle and (2) the ratio of pulmonary to systemic blood flow. Rational surgical palliation of cyanosis due to single ventricle with pulmonary stenosis is therefore directed toward altering these two determinants in a favorable direction. The creation of systemic artery-to-pulmonary artery anastomoses will increase pulmonary blood flow without directly influencing streaming. In theory, anastomosis between the right pulmonary artery and the superior vena cava both improves streaming (by forcing superior vena caval blood to enter the pulmonary artery) and increases pulmonary blood flow. Relief of pulmonary stenosis will increase pulmonary blood flow, but access to the pulmonary stenosis, particularly if it is subvalvular, is made unusually difficult by the almost invariable transposition of the great arteries. Bypass of the pulmonary stenosis by means of a tube graft is attractive because of the ease of access and because appropriate siting of the graft might encourage systemic rather than VOL.
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HOLDEN, MACARTNEY, AND IONESCU
pulmonary venous blood to enter it. However, at present there is no means of predicting the effects upon streaming of such a graft. When mitral atresia coexists with pulmonary stenosis or atresia, the pulmonary pathology tends to mask the presence of the mitral atresia, since volume flow to the left atrium is reduced. In this situation surgical attempts to improve pulmonary blood flow have invariably been fatal. T h e only surgical procedure reported to have benefited patients with mitral atresia is atrial septectomy by the Blalock-Hanlon technique [8]. For this reason the atrial septum was excised in our Patient 1. Prior to this, no communication was detected between the atria. Though it is possible that a minute communication existed but was not visualized, it is of interest that mitral atresia with premature closure of the foramen ovale has been previously described in 3 patients by Shone and Edwards [9], who suggested that pulmonary venous blood returning to the left atrium could, by retrograde flow along one pulmonary vein, anastomose with the systemic venous circulation. T h e original angiocardiograms of Patient 1 unquestionably demonstrated opacification of the left atrium from three pulmonary veins, but the fate of pulmonary venous blood thereafter was not determined with certainty. Pulmonary venous congestion was evident in the right lower zone on the preoperative chest roentgenogram, and the reticular shadowing seen in the left chest may have been the result of either arterial or venous collateral circulation. The fact that this patient survived to the age of 9 years without operation is in itself remarkable. Navarro-Lopez and co-workers [6] were able to find only 10 patients with mitral atresia reported in the literature who had survived longer than a year; 9 of them had transposition of the great arteries. In contrast, for patients with single ventricle and two atrioventricular valves to survive beyond one year is relatively common [2, 7, 101. In both our patients a complete diagnosis was made only at open-heart operation, and because of the encouraging early results of fascia lata composite grafts in the relief of right ventricular outflow obstruction at that time [3], pulmonary stenosis was relieved in the manner described. T h e immediate hemodynamic effects in both patients were satisfactory. Their death in the postoperative period was unrelated to the function of the graft. Although the late results with fascia lata composite grafts in the right ventricular outlet have been unsatisfactory [5], this is considered to be due to the use of autologous fascia lata and not to the design of the composite graft. The use of tissues preserved by fixation through permanent crosslinkages in the construction of valve-bearing conduits may prove more adequate. T h e present experience demonstrates that bypass of pulmonary stenosis or atresia in single ventricle with a valve-bearing conduit is technically feasible and is perhaps a small step toward the development of a radical corrective procedure for this abnormality.
586
THE ANNALS OF THORACIC SURGERY
Palliation of Single Ventricle
References 1. Eliot, R. S., Shone, J. D., Kanjuh, V. I., Ruttenberg, H. D., Carey, L. S., and Edwards, J. E. Mitral atresia: A study of 32 cases. A m . Heart J . 70:6, 1965. 2. Elliott, L. P., Anderson, R. C., and Edwards, J. C. T h e common cardiac ventricle with transposition of the great vessels. Br. Heart J . 26:289, 1964. 3. Ionescu, M. I., and Deac, R. C. Fascia lata composite graft for right ventricular outflow tract and pulmonary artery reconstruction. Thorax 25:427, 1970. 4. Ionescu, M. I., Macartney, F. J., and Wooler, G. H. Intracardiac renair of single ventricle with pulmonary stenosis. J . Thorac. Cardiovasc. Surg. 65:602, 1973. 5. Macartney, F. J., Holden, M. P., Scott, O., and Ionescu, M. I. Late results of reconstruction of the right ventricular outlet with fascia lata composite grafts. Am. J . Cardiol. I n press. 6. Navarro-Lopez, F., Garcia, J. M., Zomeno, M., and Llorian, A. R. C. Mitral atresia and occlusive left atrial thrombus: A case with 11 years of survival. Br. Heart J . 31:649, 1969. 7. Rahimtoola, S. H., Ongley, P. A., and Swan, H. J. C. T h e hemodynamics of common (or single) ventricle. Circulation 34: 14, 1966. 8. Redo, S. F., Engle, M. A., Ehlers, K. H., and Farnsworth, P. B. Palliative surgery for mitral atresia. Arch. Surg. 95:717, 1967. 9. Shone, J. D., and Edwards, J. E. Mitral atresia associated with pulmonary venous anomalies. Br. Heart J. 26:241, 1964. 10. Van Praagh, R., Ongley, P. A., and Swan, H. J. C. Anatomic types of single or common ventricle in man-morphologic and geometric aspects of 60 necropsied cases. A m . J . Cardiol. 13:367, 1964. 11. Watson, D. G., Rowe, R. D., Conen, P. E., and Duckworth, J. W. A. Mitral atresia with normal aortic valve. Pediatrics 25:450, 1960.
D
efinitive repair of single ventricle presents formidable technical problems. T o our knowledge there has been only one published report of intracardiac correction of single ventricle [4].The major difficulty is undoubtedly that of separating and appropriately directing the pulmonary and systemic venous return within the ventricle without compromising the conduction system or atrioventricular valve function, while at the same time creating two ventricular cavities whose functional capacity approaches that of the normal left and right ventricle. Another major problem is relieving the pulmonary outflow obstruction. I n patients without pulmonary stenosis, the high incidence of pulmonary vascular disease represents an additional hazard [7]. T h e experience in 2 patients of attempted palliation by relief of pulmonary stenosis, rather than by a shunt operation, is reported in the hope that it will contribute to the development of a procedure for radical correction of single ventricle with pulmonary stenosis. PATIENT 1
This patient had been cyanotic since birth on June 14, 1961. He had always been severely handicapped physically and at the. time of operation was unable to walk up more than a few stairs without severe dyspnea. On physical examination he was severely cyanotic with marked finger clubbing. From the Departments of Cardio-thoracic Surgery and Cardiology, The General Infirmary at Leeds and Killingbeck Hospital, and Leeds University School of Medicine, Leeds, England. Supported by the British Heart Foundation. The authors gratefully acknowledge the assistance of Mrs. Judith Ladley with this work. Accepted for publication Feb. 1, 1973. Address reprint requests to Mr. Ionescu, Department of Cardio-thoracic Surgery, The General Infirmary, Leeds, England.
578
THE ANNALS OF THORACIC SURGERY
Palliation of Single Ventricle
The arterial and venous pulses were normal. The first and second heart sounds were single, and there was a moderately loud ejection systolic murmur that was maximal in the pulmonary area. The electrocardiogram showed sinus rhythm with right atrial and right ventricular hypertrophy. The chest roentgenogram (Fig. 1) showed an enlarged heart with an uptilted apex and a left aortic arch. Neither the right atrium nor the pulmonary artery was prominent. An anomalous right upper pulmonary vein could be seen apparently entering the right atrium. The right lower pulmonary vein was grossly dilatated. The left lung field showed a coarsely reticular pattern consistent with collateral blood supply. There was also some linear atelectasis at the right base. An angiocardiogram (Fig. 2) performed in another hospital in 1962 showed that with the catheter through the “tricuspid” valve, contrast medium was injected into an enlarged, trabeculated right ventricular cavity giving rise to a transposed aorta lying above a well-defined subaortic conus. There was extreme subpulmonary stenosis, with the pulmonary valve lying slightly behind, to the left of, and at about the same horizontal level as the aortic valve. No second ventricular cavity was identified. The right upper pulmonary vein was seen to drain to the superior vena cava and the remaining pulmonary veins to the left atrium. The mitral valve was not clearly seen. On March 9, 1970, the heart was exposed through a median sternotomy. After exploration before and during perfusion, a diagnosis was made of mitral atresia with common ventricle, transposition of the great vessels, and pulmonary stenosis. The right upper pulmonary vein drained to the right superior vena cava, and the remaining pulmonary veins drained normally. However, the left atrium did not appear to communicate with either the right atrium or a ventricle. The pulmonary artery arose from a rudimentary FIG. 1 . Posteroanterior chest roentgenogram of Patient 1, showing the enlarged heart with an uplifted apex and left aortic arch. An anomalous right upper pulmonary vein apparently enters the right atrium. T h e right lower pulmonary vein is enlarged. T h e left lung field shows a coarsely reticular pattern consistent with collateral circulation. There is some linear atelectasis at the right base.
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FIG. 2. Preoperative angiocardiogram in Patient I, lateral view. W i t h the catheter through the “tricuspid” valve, contrast medium was injected into an enlarged, trabeculated right ventricular cavity (RV) from which a transposed aorta originates (AO). T h e pulmonary stenosis is indicated by an open arrow.
ventricular chamber communicating with the main (right) ventricular cavity through an 8 mm. aperture. Since no corrective operation was possible, the atrial septum was excised to relieve pulmonary venous obstruction, and a composite fascia lata graft (a valve-bearing conduit) was inserted between the rudimentary ventricular cavity and the bifurcation of the pulmonary artery. Cardiopulmonary bypass was discontinued without difficulty, but four hours after the operation the patient had a sudden cardiac arrest and could not be resuscitated. Pathological Findings. Postmortem examination showed that the immediate cause of death was a massive subarachnoid hemorrhage due to rupture of a congenital aneurysm of the circle of Willis. T h e heart (Fig. 3) weighed 150 gm. Systemic venous drainage was normal to an enlarged right atrium, which received the coronary sinus and contained the crista terminalis. The atria were in situs solitus, and the left atrium was small. T h e atretic mitral valve was represented by a dimple. T h e right upper pulmonary vein entered the superior vena cava about 4 cm. above its junction with the right atrium. T h e remaining pulmonary veins drained into the left atrium. Extensive intrapulmonary dissection of the pulmonary veins was not done. T h e atrial septum had been excised. From the right atrium an atrioventricular valve entered an enlarged ventricular chamber with coarsely trabeculated walls. This valve had four cusps and was not typical of a tricuspid valve in that there was no papillary muscle of the conus, but instead a large posteromedial cusp resembling the anterior cusp of a mitral valve. This atrioventricular valve cusp was separated from the aortic annulus by a small band of muscle. Through an 8 mm. aperture the right ventricle communicated with a rudimentary, centrally positioned anterior outflow
580
THE ANNALS OF THORACIC SURGERY
Palliation of Single Ventricle
chamber that gave origin to the pulmonary artery by way of an almost atretic outflow tract and valve. T h e aortic valve was located to the right and slightly anterior to the pulmonary valve. A fascia lata composite graft had been used to connect the rudimentary outflow chamber (which was in no way related to the left atrium) to the bifurcation of the pulmonary artery. T h e middle and lower lobes of the right lung were congested and edematous, as was the left lung.
A
B
FIG. 3. T h e heart from Patient 1. ( A ) Anterior view of the heart with the composite fascia lata graft inserted as a bypass from the rudimentary ventricle to the bifurcation of the pulmonary artery. ( B ) T h e interior of the heart with the right atrium widely opened. T h e left atrium is seen through the atrial septum removed at operation. T h e atrioventricular valve, containing four cusps, opens into a coarsely tmbeculated, large ventricular chamber. (CS = ostium of the coronary sinus.) ( C ) T h e interior of the heart with the ventricle opened. T h e atrioventricular valve (AV) is separated from the aortic valve (+) by a small band of muscle (white arrow) and by the atretic mitral valve ( M ) . T h e black arrow points toward the opening of the pulmonary artery. (CS = crista supraventricularis; *+ = rudimentary outflow chamber.)
C VOL.
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1973
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HOLDEN. MACARTNEY, AND IONESCU PATIENT 2
This patient, together with a normal twin brother, was born in 1952 after an uncomplicated pregnancy. She was cyanotic from birth and squatted frequently. At the time of operation when she was 18 years old, she could not walk more than 100 yards on the flat and was severely cyanotic with gross finger clubbing. Her arterial pulses were normal, but there was a 2 cm. “a” wave in the jugular venous pulse. There was a left parasternal heave, and the second heart sound was palpable. On auscultation the first heart sound was followed by an aortic ejection click. T h e second heart sound was single, and there was a moderately loud systolic ejection murmur in the pulmonary area. T h e chest roentgenogram (Fig. 4) was characteristic of corrected transposition with pulmonary stenosis, there being a narrow heart with oligemic lung fields and with the ascending aorta prominent on the left upper cardiac border. T h e electrocardiogram showed P pulmonale with a mean frontal QRS axis of +135 degrees. Small Q waves were present in leads 111, aVF, and V1, but not in the left precordial leads. Cardiac catheterization and angiocardiography performed in 1954 and April, 1970, had demonstrated corrected transposition of the great arteries with pulmonary stenosis. T h e exact ventricular anatomy was not clarified, though the possibility of common ventricle had been raised. On May 11, 1970, an operation was carried out under heart-lung bypass. On opening the heart it became apparent that there was a single ventricle with inversion of the infundibulum and severe pulmonary stenosis. T h e left atrioventricular valve annulus was hypoplastic, and for this reason in particular no attempt was made to create a ventricular septum. Instead, a FIG. 4 . Posteroanterior chest roentgenogram of Patient 2.
582
THE ANNALS OF THORACIC SURGERY
Palliation of Single Ventricle
composite fascia lata graft was inserted as a bypass between the ventricle and the pulmonary artery. Perfusion was terminated without difficulty. Tracheostomy was performed on the second postoperative day because of pulmonary dysfunction, and as this continued notwithstanding, on the third postoperative day the distal end of the graft tube was constricted with a Teflon band to reduce the distal systolic pressure from 40 to 20 mm. Hg. For the next three weeks cardiac output remained adequate as judged by cerebral, renal, and skin perfusion. Cyanosis was judged clinically to be less than it had been preoperatively. The arterial Po2 was 80 mm. Hg with the patient breathing 40% oxygen. During the third postoperative week the patient developed pyrexia. At the same time multiple stitch abscesses appeared in the median sternotomy wound; they grew a coagulase-negative Staphylococcus and subsequently Candida and coliform bacilli, which also appeared in the urine. Despite vigorous antibiotic treatment, the patient remained pyrexial and developed signs of intracranial infection. One month after the operation the patient developed peripheral edema and elevation of the jugular venous pressure that responded to diuretic therapy. She died six weeks after the operation with overwhelming infection. Pathological Findings. Postmortem examination showed inflammation of the pericardium with areas of mottling and petechial hemorrhages in the myocardium. There were diffuse petechial hemorrhages in the brain. The anatomy of the heart was typical of a single ventricle with inversion of the infundibulum (Fig. 5). Pulmonary and systemic venous returns were normal. The left atrium was rather small. Two atrioventricular valves that were in fibrous continuity entered a finely trabeculated common ventricle. The valve entering from the right atrium was tricuspid, whereas the valve from the left atrium was bicuspid with a valve annulus that would only admit the tip of a little finger. The pulmonary valve was bicuspid and severely stenotic, having a 1 mm. orifice. It was in tenuous continuity with the right atrioventricular valve. The aorta arose from a subaortic chamber lying anterior to, above, and to the left of the common ventricle. The aortic valve lay above, anterior to, and to the left of the pulmonary valve, and the ascending aorta took a course typical for corrected transposition. A composite fascia lata graft had been inserted between the site of the ventriculotomy and the bifurcation of the pulmonary artery. The pulmonary artery had been banded.
Comment Opinions differ on whether or not mitral atresia should be included in the category of single ventricle [2, 101. Mitral atresia presents even more formidable problems in surgical correction than does common ventricle with two patent atrioventricular valves, so there are good, practical reasons for
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HOLDEN, MACARTNEY, AND IONESCU
A
B FIG. 5. T h e heart from Patient 2. ( A } Anterolateral view of the heart. (RA=right atrium; A 0 = ascending aorta; FLG = fascia lata composite graft inserted as a bypass from the common ventricle to the bifurcation of the pulmonary artery.) T h e graft was banded at its distal end. ( B ) View of the atria. T h e atrial septum was removed in order to show both atrioventricular valves. T h e right atrium is considerably bigger than the left. (RAV = right atrioventricular valve [tricuspid]; LAV = left atrioventricular valve [bicuspid].)
584
THE ANNALS OF THORACIC SURGERY
Palliation of Single Ventricle
C FIG. 5 (Continued). ( C ) T h e interior of the heart with the ventricle and aorta opened. (TV = tricuspid valve; MV = mitral value; AV = aortic value; * = subaortic chamber.) T h e probe was passed through the pulmonary artery.
separating mitral atresia from single ventricle. However, since we are concerned here with the relief of pulmonary stenosis rather than the division of a common ventricle into two functioning cavities, the nomenclature of Eliot and Elliott and their associates [l, 21 has been adopted. Hemodynamically, single ventricle is characterized by bidirectional shunting of blood at the ventricular level. Mixing of systemic and pulmonary venous blood is not always complete [7], though it seems likely that the addition of mitral atresia increases mixing since it then occurs at the right atrial level as well. The degree of systemic desaturation in single ventricle is therefore dependent upon (1) streaming within the ventricle and (2) the ratio of pulmonary to systemic blood flow. Rational surgical palliation of cyanosis due to single ventricle with pulmonary stenosis is therefore directed toward altering these two determinants in a favorable direction. The creation of systemic artery-to-pulmonary artery anastomoses will increase pulmonary blood flow without directly influencing streaming. In theory, anastomosis between the right pulmonary artery and the superior vena cava both improves streaming (by forcing superior vena caval blood to enter the pulmonary artery) and increases pulmonary blood flow. Relief of pulmonary stenosis will increase pulmonary blood flow, but access to the pulmonary stenosis, particularly if it is subvalvular, is made unusually difficult by the almost invariable transposition of the great arteries. Bypass of the pulmonary stenosis by means of a tube graft is attractive because of the ease of access and because appropriate siting of the graft might encourage systemic rather than VOL.
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HOLDEN, MACARTNEY, AND IONESCU
pulmonary venous blood to enter it. However, at present there is no means of predicting the effects upon streaming of such a graft. When mitral atresia coexists with pulmonary stenosis or atresia, the pulmonary pathology tends to mask the presence of the mitral atresia, since volume flow to the left atrium is reduced. In this situation surgical attempts to improve pulmonary blood flow have invariably been fatal. T h e only surgical procedure reported to have benefited patients with mitral atresia is atrial septectomy by the Blalock-Hanlon technique [8]. For this reason the atrial septum was excised in our Patient 1. Prior to this, no communication was detected between the atria. Though it is possible that a minute communication existed but was not visualized, it is of interest that mitral atresia with premature closure of the foramen ovale has been previously described in 3 patients by Shone and Edwards [9], who suggested that pulmonary venous blood returning to the left atrium could, by retrograde flow along one pulmonary vein, anastomose with the systemic venous circulation. T h e original angiocardiograms of Patient 1 unquestionably demonstrated opacification of the left atrium from three pulmonary veins, but the fate of pulmonary venous blood thereafter was not determined with certainty. Pulmonary venous congestion was evident in the right lower zone on the preoperative chest roentgenogram, and the reticular shadowing seen in the left chest may have been the result of either arterial or venous collateral circulation. The fact that this patient survived to the age of 9 years without operation is in itself remarkable. Navarro-Lopez and co-workers [6] were able to find only 10 patients with mitral atresia reported in the literature who had survived longer than a year; 9 of them had transposition of the great arteries. In contrast, for patients with single ventricle and two atrioventricular valves to survive beyond one year is relatively common [2, 7, 101. In both our patients a complete diagnosis was made only at open-heart operation, and because of the encouraging early results of fascia lata composite grafts in the relief of right ventricular outflow obstruction at that time [3], pulmonary stenosis was relieved in the manner described. T h e immediate hemodynamic effects in both patients were satisfactory. Their death in the postoperative period was unrelated to the function of the graft. Although the late results with fascia lata composite grafts in the right ventricular outlet have been unsatisfactory [5], this is considered to be due to the use of autologous fascia lata and not to the design of the composite graft. The use of tissues preserved by fixation through permanent crosslinkages in the construction of valve-bearing conduits may prove more adequate. T h e present experience demonstrates that bypass of pulmonary stenosis or atresia in single ventricle with a valve-bearing conduit is technically feasible and is perhaps a small step toward the development of a radical corrective procedure for this abnormality.
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THE ANNALS OF THORACIC SURGERY
Palliation of Single Ventricle
References 1. Eliot, R. S., Shone, J. D., Kanjuh, V. I., Ruttenberg, H. D., Carey, L. S., and Edwards, J. E. Mitral atresia: A study of 32 cases. A m . Heart J . 70:6, 1965. 2. Elliott, L. P., Anderson, R. C., and Edwards, J. C. T h e common cardiac ventricle with transposition of the great vessels. Br. Heart J . 26:289, 1964. 3. Ionescu, M. I., and Deac, R. C. Fascia lata composite graft for right ventricular outflow tract and pulmonary artery reconstruction. Thorax 25:427, 1970. 4. Ionescu, M. I., Macartney, F. J., and Wooler, G. H. Intracardiac renair of single ventricle with pulmonary stenosis. J . Thorac. Cardiovasc. Surg. 65:602, 1973. 5. Macartney, F. J., Holden, M. P., Scott, O., and Ionescu, M. I. Late results of reconstruction of the right ventricular outlet with fascia lata composite grafts. Am. J . Cardiol. I n press. 6. Navarro-Lopez, F., Garcia, J. M., Zomeno, M., and Llorian, A. R. C. Mitral atresia and occlusive left atrial thrombus: A case with 11 years of survival. Br. Heart J . 31:649, 1969. 7. Rahimtoola, S. H., Ongley, P. A., and Swan, H. J. C. T h e hemodynamics of common (or single) ventricle. Circulation 34: 14, 1966. 8. Redo, S. F., Engle, M. A., Ehlers, K. H., and Farnsworth, P. B. Palliative surgery for mitral atresia. Arch. Surg. 95:717, 1967. 9. Shone, J. D., and Edwards, J. E. Mitral atresia associated with pulmonary venous anomalies. Br. Heart J. 26:241, 1964. 10. Van Praagh, R., Ongley, P. A., and Swan, H. J. C. Anatomic types of single or common ventricle in man-morphologic and geometric aspects of 60 necropsied cases. A m . J . Cardiol. 13:367, 1964. 11. Watson, D. G., Rowe, R. D., Conen, P. E., and Duckworth, J. W. A. Mitral atresia with normal aortic valve. Pediatrics 25:450, 1960.