Indication and Technique of Total Correction of Tetralogy of Fallot in 228 Patients

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1 Indication and Technique of Total Correction of Tetralogy of Fallot in 228 Patients Qingyu Wu, MD Department of Cardiac Surgery, Cardiovascular Institute and Fu Wai Hospital, Chinese Academy of Medical Sciences, Beijing, People's Republic of China Background. Several factors, such as old age, high hemoglobin level, pulmonary artery hypoplasia, and diminutive left ventricle, have been identified as high risk factors for operative mortality. This group of patients includes all these factors. Methods. Between September 1987 and March 1995, I performed total correction of tetralogy of Fallot on 228 unselected consecutive patients at Fu Wai Hospital in Beijing. There were 140 male and 88 female patients. Results. Only 2 patients died of nonsurgical causes postoperatively. The mortality was 0.9%. The remaining patients recovered uneventfully. The late mortality was 1.8% (4/228). Conclusions. The results suggested that hypoplastic pulmonary artery and left ventricle were not an absolute contraindication of total correction of tetralogy of Fallot. High hematocrit and old age were also not high risk factors causing death. The key factor was to correct the pathology completely and manage the complications properly. (Ann Thorac Surg 1996;61: ) he first completed repair of tetralogy of Fallot was T successfully performed by C. Walton Lillehei and his team in 1954 [1]. Many advances have been achieved to improve the results of tetralogy of Fallot since then [2-4]. The present report describes my personal experience in surgical management of tetralogy of Fallot at Fu Wai Hospital in Beijing, China, in recent years. Patients and Methods Patients Between September 1987 and March 1995, I performed total correction in 228 unselected consecutive patients with tetralogy of Fallot at Fu Wai Hospital in Beijing, China. There were 140 male and 88 female patients. Age ranged from I year 6 months to 37 years (average, years). One patient had previously received a rightsided Blalock shunt. The preoperative variables of this group of patients are summarized in Table 1. Operative Methods The operation was performed under cardiopulmonary bypass with hypothermia (nasopharyngeal temperature was between 20 and 24 C). A median sternotorny was used routinely. Crystalloid cardioplegic solution was given from the root of aorta at 30-minute intervals, and ice-saline solution was used topically for the additional protection of myocardium. The right atrium was opened routinely for the inspection of the atrial septal defect, foramen ovale, ventricular septal defect (VSD), and tricuspid valve, and the left ventricle was vented through Accepted for publication Feb 6, Address reprint requests to Dr Wu, Department of Cardiac Surgery, Cardiovascular Institute and Fu Wai Hospital, Chinese Academy of Medical Sciences, Beijing , PR China. the interatrial septum. Reconstruction of the right ventricular outflow tract (RVOT) was completed before release of the aortic clamp. Aortic clamping time was 18 to 129 minutes (average, 61 _+ 20 minutes), and the cardiopulmonary bypass time was 39 to 197 minutes (average, minutes). Operative findings are summarized in Table 2. RECONSTRUCTION OF THE RIGHT VENTRICULAR OUTFLOW TRACT. An oblique or longitudinal right ventriculotomy was used except when an abnormal coronary artery necessitated a transverse incision in the RVOT. The incision was extended to the pulmonary artery where necessary. The thickness of the right ventricular wall was kept at 0.5 to 0.8 cm. All abnormal muscles were resected corresponding to the pathology of the RVOT, and pulmonary valvotomy was finished. The VSD was closed with a similar-sized Dacron patch. Then a Hegar dilator was used to measure the diameter of the narrowest portion of RVOT, pulmonary annulus, and pulmonary trunk to determine the methods of reconstruction of the RVOT, judged by a criterion that was obtained from my experience: Weight (kg) Diameter (mm) > by The Society of Thoracic Surgeons /96/$15.00 Published by Elsevier Science Inc PlI S (96)

2 - subacute 1770 WU Ann Thorac Surg CORRECTION OF TETRALOGY OF FALLOT 1996;61: Table 1. Preoperative Variables Variable Value Age Mean (y) Range (y) >16 y 55 (24.1%) Weight (kg) 8-78 Symptom Syncope 58 (25.4%) Squatting 196 (86.0%) Cyanosis 212 (93.0 /,) Clubbing fingers and toes 206 (90.4%',,) Signs Systolic murmur <Grade 2 60 (26.3%) >Grade (73.7%) Systolic & diastolic murmur 3 (1.3%) Systolic thrill 93 (40.8%) ECG RVH 159 (70.0%) RVH + dilation of right atrium 55 (24.1%) IRBBB 11 (4.8%) WPW syndrome 1 (0.4%) Rhythm of junction area 2 (0.88%) Chest roentgenogram Boot-shaped heart & oligemia of 100% the lung Cardiothoracic ratio (mean, 0.52) Hemoglobin level (g/l) (mean, ) Hemoglobin level >180 g/l 150 (66%) Oxygen pressure (ram Hg) Oxygen saturation (%) (75% -+ 9%) Echocardiography Typical TOF 228 (100'7'0) Pulmonary valve regurgitation 3 (1.3%) Tricuspid valve regurgitation 6 (2.6 /,) Preoperative catheterization 165 (72%) Right ventricular systolic pressure (mean, 93) (mm Hg) Atrial communication 30 (13.2%) Angiocardiography Typical TOF 160 (70.2%) Pulmonary atresia 2 (0.9%) Absent pulmonary, valve syndrome 3 (1.3%) Hypoplasia of pulmonary arteries 40 (17.5%) Stenosis in the pulmonary valve 20 (8.8%) annulus Stenosis in the origin of the LPA 15 (6.6%) Stenosis in the origin of the RPA 7 (3.1%) Absent left PA 2 (0.9%) ECG electrocardiogram; IRBBB intermittent right bundle-branch block; LPA left pulmonary artery; PA pulmonary' artery; RPA - right pulmonary artery; RVH right ventricular hypertrophy; TOF = tetralogy of Fallot. If the RVOT was large enough I closed the right ventriculotomy directly. If it was smaller than the criterion, a suitably sized and shaped patch was used to widen the RVOT. If the RVOT obstruction was because of diffuse hypoplasia or stenosis in the infundibulum and the pulmonary annulus and valves and it would be smaller than the criterion even after dissection of all abnormal muscles, a transannular patch was required. The size and shape of the patch required were decided corresponding to the pathology of the RVOT and measured by holding the edges of the incision opened at valve level with the Hegar dilator. The diameter of the newly created pulmonary annulus and RVOT should not be more than 1 mm larger than the criterion. I measured twice with a Hegar dilator before the reconstruction of the RVOT and just before finishing the reconstruction. The principle was to release the obstruction of RVOT and pulmonary artery as much as possible and to injure the tissue of myocardium, coronary artery branch, and pulmonary valve as little as possible. For details of the reconstruction of the RVOT in this group, see Table 3. REPAIR OF VENTRICULAR SEPTAL DEFECT. The VSD was closed with a Dacron patch and sutured continuously with 5/0 or 4/0 Prolene (Ethicon, Somerville, NJ) in 109 patients. In the other 119 patients, two to four mattress Table 2. Operative Findings Finding No. of Patients Aortic overriding >50 /',, 146 (64.0'7' ) <50% 82 (36.0%) Ratio of aortic diameter/pulmonary diameter >3 125 (54.9'7'o) (25.4%) < (19.7%) Right ventricular outflow tract obstruction Isolated infundibular 32 (14.0 /i,) Combined infundibular & valvular 131 (57.5%) Infundibular, valvular, & pulmonary 57 (25.0%) annulus Pulmonary atresia 3 (1.3 /,) Absent left pulmonary artery 2 (0.9%) Absent pulmonary valve syndrome 3 (1.3%) Bicuspid pulmonary valve 162 (27.2%) Ventricular septal defect Subarterial type 22 (9.6%) Infracristal type 206 (90.3 %) [atrogenic ~pe 1 (0.4%) Reopen 1 (0.4%) Associated anomaly ASD 22 (9.6%) Patent foramen ovale 46 (20.2%) PDA 1 (0.4%) Left superior vena cava 7 (3.1%) Tricuspid insufficiency 6 (2.2%) SBE 2 (0.9'70) Anomalous coronary artery 4 (1.8%) ASD atrial septal defect; PDA patent ductus arteriosus; SBE bacterial endocarditis.

3 Ann Thorac Surg WU ;61: CORRECTION OF TETRALOGY OF FALLOT Table 3. Reconstruction of the Right Ventricular Outflow Tract Reconstruction of the RVOT Directly closed Pericardial patch Pericardial patch covered with Dacron cloth Transannular patch Aortic homograft with noncoronary cusp and anterior leaflet Pericardium & pericardial monocusp Pericardial patch Separated patches of the pulmonary artery and outflow tract Aortic homograft implantation (for absent pulmonary valve syndrome) Conduit of aortic homograft RVOT right ventricular outflow tract. No. of Patients 19 (8.3%) 40 (17.5%) 98 (43.0%) 62 (27.0 /,.) 21 (9.2%) 11 (4.8%) 30 (13.2%) 4 (1.8%) 3 (1.3%) 2 (0.9%) sutures were used at the "risk area" and a continuous suture completed the remaining margin. MANAGEMENT OF ASSOCIATED MALFORMATIONS. The patent foramen ovale and atrial septal defect were directly sutured in 60 patients and repaired using a patch in 8 patients. The patent ductus arteriosus was closed via main pulmonary artery under low perfusion flow. Of the 4 patients with a large anomalous right coronary branch across the surface of the RVOT, 1 was repaired with a conduit of aortic homograft because of associated pulmonary atresia, and in the others the RVOT was reconstructed by transverse incision parallel to the anomalous branch. In the patients with subacute bacterial endocarditis, the infective neoplasm was excised thoroughly. De Vega annuloplasty was performed in 5 patients with tricuspid regurgitation. REOPERATION. Three patients who were operated on by other surgeons previously received successful reoperation. One of the patients underwent sternotomy at another hospital but received no repair for the cause of small left ventricle, hypoplastic pulmonary artery, and tricuspid insufficiency. Another patient had a reopened VSD and tricuspid regurgitation 1 year after operation, and the third patient had iatrogenic VSD, that is, caused by perforation during removal of muscle bundles, and residual RVOT stenosis 3 weeks after the initial operation. HEMODYNAMIC MEASUREMENT. A hemodynamic measurement was done before closing the chest in the first 58 consecutive patients. A right ventricular systolic pressure of less than 60 mm Hg, a pressure gradient of right ventricle to pulmonary artery of less than 40 mm Hg, and a ratio of right and left ventricular systolic pressures of less than 0.75 were recorded. We did not measure these variables in the following patients because of their stable hemodynamics. ECHOCARDIOGRAPHIC EXAMINATION. Thirty-one patients with a transannular patch and a monocusp valve include 21 with homograft patches were investigated by twodimensional and Doppler echocardiography through a saline water cyst on the surface of the right ventricle with the cardiopulmonary bypass off. No pulmonary regurgitation or residual shunt of VSD was found. Results Survival Two patients died in the hospital, for a mortality rate of 0.9%. One died of acute renal failure because of bleeding from the liver caused by the right thoracentesis. The other I died of intractable ventricular arrhythmia caused by hypokalemia. Postoperative low cardiac output syndrome occurred in 6 patients, adult respiratory depressing syndrome in 3, pulmonary edema in 3, chylothorax in 1, reopening of the chest for blood oozing in 2, transient third-degree atrioventricular block in 2, and infection of the posterior sternum in 1. All of them recovered and were discharged from the hospital. Follow-up Two hundred twenty-eight patients (100%) were followed up from 6 months to 8 years (average, 62 ~ 2 months), for a total of 5,980 patient-years. The 5-year actuarial survival was 98.2%. There were four late deaths, all of which occurred at home: 2 patients died of subacute bacterial endocarditis, and the other 2 patients died of unclear causes. The remaining patients were doing well. The cardiac function of 203 patients (89.0%) was New York Heart Association class I, and 21 patients (9.2%) were in class II. There were 10 women between 22 and 37 years old; 7 of them had babies. Comment Indication of Total Correction Several factors, such as old age, high hemoglobin level, pulmonary artery hypoplasia, and diminutive left ventricle, have been identified as risk factors for operative mortality in many previous published series [5, 6]. In our group of 228 unselected consecutive patients, all these risk factors were present, but only 2 patients died of nonsurgical causes postoperatively. The early and late results were satisfactory. In this group 125 patients had a ratio of the diameter of aorta to that of pulmonary trunk more than 3 (in 3 patients even more than 4.5), 2 patients had an absent left pulmonary artery, and 9 patients had an obviously smaller diastolic volume of the left ventricle displayed by two-dimensional echocardiography and angiocardiography as well as at operation; all patients underwent total correction and had a satisfactory result. In the last 4 years I have relied primarily on echocardiography to confirm the preoperative diagnosis of tetralogy of Fallot. Except where the diagnosis needs to be differentiated, catheterization and angiocardiography (Fig 1) were not necessary for the operation. Although

4 1772 WU Ann Thorac Surg CORRECTION OF TETRALOGY OF FALLOT 1996;61: A B Fig 1. (A-O Thirty-one-year-old woman with tetralogy of Fallot, hypoplasia of the pulmonary artery, and diminutive left ventricle, who underwent operation on November 1, (D) Eight-year-old girl with tetralogy of Fallot, left superior vena cava, and atrial septal defect, who underwent operation on February 23, Both patients are doing well now. D these patients needed isotropic drugs or ventilation support within the first 3 days of operation, all patients were discharged. Therefore, a small left ventricle as a contraindication to total correction will need further consideration. Although the condition of the pulmonary artery could not be clearly shown by two-dimensional echocardiography or even by angiocardiography before operation, careful investigation and estimation during operation is very important. Two patients who were considered to have a contraindication to total correction underwent total repair with an uneventful course. Three other patients displayed severe stenosis at the origin of both left and right pulmonary arteries by angiocardiography but the stenosis was not demonstrated at operation. A high hemoglobin level was considered another highrisk factor for total correction by some authors [2]. In the group presented here, 150 patients (66%) with a hemoglobin level of more than 180 g/l underwent complete repair without death. One of them, a 25-year-old man with a hemoglobin level of 320 g/l and a hematocrit of 90% as well as frequent syncope, underwent an uneventful course postoperatively. In these patients there was usually severe stenosis in the RVOT, which might not be difficult to release, and the results were often very good after operation. In contrast to these, in patients with a subarterial VSD, in whom the symptoms were usually not severe and the hemoglobin level not high but the repair might be more complicated, often needed a transannular patch [7, 8].

5 Ann Thorac Surg WU ;61: CORRECTION OF TETRALOGY OF FALLOT Technique of Operation The length of the right ventriculotomy was just long enough to repair the VSD. This not only obtains good exposure for the operation but also preserves myocardium and coronary artery branches. Although the right atrial approach to repair a VSD and a small incision in the pulmonary artery to relieve RVOT stenosis have been advocated [4], for the patients with severe diffuse hypoplasia RVOT and children or adult patients a right ventriculotomy was necessary, because it would be difficult to repair the VSD through the atrial approach and resect so much abnormal muscle through the small incision. I did not find evidence of damage to the right ventricular function in my patients. The criterion of reconstruction of RVOT described above was very important in my experience. If the criterion was too large an unnecessary transannular patch may be inserted in some patients, which may cause long-term significant pulmonary regurgitation [2, 8] and also decrease the right ventricular function. If it was small, a high residual pressure gradient between right ventricle and pulmonary artery could remain in some patients and increase the load on the right ventricle. My criterion proved reliable and simple. After operation the ratio of peak pressure of right ventricle to that of left ventricle was less than 0.75 in 58 measured patients. The peak pressure of the right ventricle gradually would come down further later [9]. The material used for reconstruction of RVOT in some patients was a piece of pericardium. If the width of the patch was more than 1 cm, I used a Dacron patch with autologous pericardium underneath to prevent paradoxical movement of the pericardium, aneurysm formation in the RVOT, and bleeding. The effect of the transannular patch with or without a rnonocusp may be similar [2]. My experience from the two-dimensional echocardiography on the surface of the right ventricle showed that a patch with a monocusp, especially a homograft patch, could decrease pulmonary artery regurgitation efficiently. This is reasonable because construction of the natural monocusp may be more efficient. The long-term results of homograft use are quite good in aortic valve replacement [10]. It would be better in a pulmonary position. The transannular patch is only indicated for patients with a small pulmonary annulus and diffuse hypoplastic RVOT and for some patients with a subarterial VSD. The transannular patch accounted for 62 patients (27%) in this group because even though pulmonary regurgitation was well tolerated [11-13], the long-term result may not be good enough for some patients [14]. An overly wide transannular patch may cause severe regurgitation of the pulmonary valve and intractable congestive right heart failure in patients with poor development of the pulmonary artery and high pulmonary resistance. The diastolic volume of the right ventricle is increased and the ejection fraction of the right ventricle is decreased [2], and reoperation was considered in 5% patients due to pulmonary regurgitation [15], so the function of pulmonary valve should be preserved as much as possible. A transannular patch with a monocusp was useful and did not cause stenosis in the RVOT in long-term follow-up [16]. When an aortic homograft with a mitral valve is used in reconstruction of the RVOT, one should be aware that the rnitral valve may not be wide enough. When a continuous suture is used to repair of VSD, the shortening of the area of tricuspid valve and residual shunt through the rupture of the tricuspid valve and VSD should be carefully avoided. The iatrogenic VSD caused by excessive excision of the abnormal septal muscle bundle should be patched with interrupted sutures. Postoperative Management The mean blood pressure of the patients was kept between 60 and 70 mm Hg as long as the circulation of the extremities was good and the urine output was not less than 1 ml/kg of body weight per hour. Maintenance of the blood volume with fresh frozen blood plasma or albumin was necessary, especially in adult patients, but the infusion of liquid should be controlled in patients with pulmonary regurgitation and right heart failure, in whom long-term digoxin, diuretic, and vasodilator administration was necessary to maintain heart function. Conclusion I conclude that the key factor in the total correction of tetralogy of Fallot is to correct the pathology completely, to protect the myocardium, and to manage the complications properly. Most patients, even with hypoplasia of pulmonary artery, a small left ventricle, and a high hemoglobin level, can obtain a satisfactory result from total correction of tetralogy of Fallot. References 1. Lillehei CW, Cohen M, Warden HE, et al. Direct vision intracardiac surgical correction of the tetralogy of Fallot, pentalogy of Fallot, and pulmonary atresia defects: report of first ten cases. Ann Surg 1955;142: Kirklin JW, Barratt-Boyes BG. Ventricular septal defect and pulmonary stenosis or atresia. In: Kirklin JW, Barratt-Boyes BG, eds. Cardiac surgery. 2nd ed. New York: Churchill Livingstone, 1993: Murphy JG, Gersh BJ, Mair DD, et al. Long-term outcome in patients undergoing surgical repair of tetralogy of Fallot. N Engl J Med 1993;329: Starnes VA, Luciani GB, Latter DA. Current surgical management of tetralogy of Fallot. Ann Thorac Surg 1994;58: Wei WZ. The experience of the total correction of tetralogy of Fallot. The new progress in clinical research of cardiovascular disease. Beijing, 1989: Kirklin JW, Blackstone EH, Jonas RA, et al. Morphologic and surgical determinants of Fallot and pulmonary stenosis. A two-institution study. J Thorac Cardiovasc Surg 1992;103: Okita Y, Miki S, Ueda Y, et al. Early and late results of repair of tetralogy of Fallot with subarterial ventricular septal defect. A comparative evaluation of tetralogy with perimembranous ventricular septal defect. J Thorac Cardiovasc Surg 1995;110: Neirotti R, Galindez E, Kreutzer G, et al. Tetralogy of Fallot with subpulmonary ventricular septal defect. Ann Thorac Surg 1978;25:51-6.

6 1774 wu Ann Thorac Surg CORRECTION OF TETRALOGY OF FALLOT 1996;61: Goor DA, Smolinsky A, Mohr R, Caspi J, Shem-Tov A. The drop of residual right ventricular pressure 24 hours after conservative infundibulectomy in repair of tetralogy of Fallot. J Thorac Cardiovasc Surg 1981;81: O'Brien M, Stafford G, Gardner M, et al. The viable cryopreserved allograft aortic valve. J Cardiac Surg 1978;2(Suppl): Kirklin JW, Blackstone EH, Kirklin JK, et al. Surgical results and protocols in the spectum of tetralogy of Fallot. Ann Surg 1983;198: Zhao HX, Miller DC, Reitz BA, et al. Surgical repair of tetralogy of Fallot. J Thorac Cardiovasc Surg 1985;89: Walsh EP, Rockenmacher S, Keane JF, et al. Late results in patients with tetralogy of Fallot repaired during infancy. Circulation 1988;77: Horneffer PJ, Zahka KG, Rowe SA, et al. Long-term results of total repair of tetralogy of Fallot in childhood. Ann Thorac Surg 1990;50: Ebert PA. Second operations for pulmonary stenosis or insufficiency after repair of tetralogy of Fallot. Am J Cardiol 1982;50: Gundry SR, Razzouk AJ, Boskind JF, Bansal R, Bailey LL. Fate of the pericardial monocusp pulmonary valve for right ventricular outflow tract reconstruction. Early function, late failure without obstruction. J Thorac Cardiovas Surg 1994;107: INVITED COMMENTARY I appreciate this opportunity to review these remarkable results in the total correction of tetralogy of Fallot in 228 unselected, consecutive patients over an 8-year period. The hospital mortality was less than 1%, and the late mortality, in the 100% follow-up from 6 months to 8 years, was less than 2%. The operations were carried out at the Fu Wai Hospital in Beijing, and the results may be the best ever reported for a similar series undergoing total correction. I spent 3 days at Fu Wai Hospital in November 1991 as a Visiting Professor, and I can add further testimony to the excellence of cardiovascular treatment in China's best-known teaching hospital. The author, Dr Qingyu Wu, concludes from his experience that the high-risk factors often cited by others such as hypoplastic pulmonary artery, diminutive left ventricle, old age, and high hematocrit need not contraindicate total corrections. From the earliest days, I have expressed similar judgments. In fact, I have long regarded old age (in tetralogy meaning 20 to 40 years) and severe polycythemia as actually favorable risk factors. The pathology was generally less severe in older patients, and the severe polycythemia made it possible to perform corrections with little or no foreign blood. Doctor Wu quite correctly concludes that the "key factor was to correct the pathology completely." To accomplish that, he made frequent use of the outflow patch whenever indicated. This valuable concept has stood the test of time, since my colleagues and I introduced it clinically in C. Walton Lillehei, MD, PhD 73 Otis Lane St. Paul, MN Bound volumes available to subscribers Bound volumes of the 1995 issues of The Annals of Thoracic Surgery are available only to subscribers from the Publisher. The cost is $99.00 (outside US add $25.00 for postage) for volumes 59 and 60. Each bound volume contains a subject and author index, and all advertising is removed. The binding is durable buckram with the name of the journal, volume number, and year stamped on the spine. Payment must accompany all orders. Contact Elsevier Science Inc, 655 Avenue of the Americas, New York NY 10010; or telephone (212) (facsimile: (212) ).