ABSTRACT In general, it has been thought that

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1 Pulmonary Valve Replacement for Regurgitation after Repair of Tetralogy of Fallot Gregory A. Misbach, M.D., Kevin Turley, M.D., and Paul A. Ebert, M.D. ABSTRACT In general, it has been thought that pulmonary valve insufficiency is well tolerated when the valve is excised or when the pulmonary annulus has been widened with an outflow patch during repair of tetralogy of Fallot. However, when pulmonary regurgitation is massive or when it is combined with other causes of right ventricular failure, progressive right ventricular dilation may occur in some patients. Pulmonary valve replacement has not been commonly used in the past. From January, 1980, to August, 1982, 12 patients, 11 months to 17 years old, had pulmonary regurgitation treated by insertion of a valve in the pulmonary position 4% months to 11 years after initial repair of tetralogy of Fallot. All patients had progressive right ventricular failure not responsive to medical management. There were no major outflow tract obstructions, residual ventricular septa1 defects, or persistent aortopulmonary shunts. All 12 patients underwent patch reconstruction of the right ventricular outflow tract that allowed placement of a larger valve. There have been no operative or late deaths, and each patient has had improvement in functional status. One patient required tricuspid valve replacement 1% years after pulmonary valve replacement to achieve sustained relief of symptoms. Only 1 other patient required subsequent operation; this was for pacemaker lead changes. These eariy results suggest that in patients with right ventricular failure, attention should be directed to pulmonary regurgitation since this is a component of failure that is reversible; pulmonary valve replacement carries a low risk, and it can relieve symptoms and prevent further deterioration of right ventricular function. From the Department of Surgery, University of California, San Francisco, San Francisco, CA. Presented in part at the Nineteenth Annual Meeting of The Society of Thoracic Surgeons, San Francisco, CA, Jan 17-19, Address reprint requests to Dr. Misbach, Division of Cardiothoracic Surgery, Department of Surgery, RF-25, University of Washington School of Medicine, Seattle, WA The extent of disability and the number of deaths from pulmonary regurgitation remain unanswered questions of long standing. Experimental pulmonary regurgitation has been reported not to have substantial adverse hemodynamic effects [l], and patients have tolerated isolated pulmonary regurgitation for decades before any symptoms develop [2]. However, a small number of patients experience disability from pulmonary regurgitation after repair of tetralogy of Fallot [3], and some studies have shown a higher hospital mortality among patients in whom a transannular patch is used in tetralogy repair [4, 51. Many reports have discussed the desirability of avoiding transannular patches and the resultant pulmonary regurgitation whenever possible without leaving excessive pulmonary outflow obstruction [4-61. In those patients in whom severe pulmonary regurgitation could not be avoided and in whom right ventricular failure becomes symptomatic, medical management may not always be successful. 'This report describes the surgical treatment of these patients with in situ pulmonary valve replacement. Patients and Method Twelve patients with pulmonary regurgitation after previous repair of tetralogy of Fallot underwent pulmonary valve replacement at the University of California, San Francisco, between January, 1980, and August, There were 6 boys and 6 girls ranging in age from 11 months to 17 years at the time of pulmonary valve replacement, which was performed 4% months to 11 years after initial repair of tetralogy (Table). All 12 patients had symptoms of progressive right heart failure that were not controlled by medical management. All patients had pulmonary reppigitation by angiography. Two patients had right ventricle-pulmonary artery gradients of 40 mm Hg, and the other 10 had gradients of less than 32 mm Hg. No patient 684

2 685 Misbach, Turley, and Ebert: Pulmonary Valve Replacement after TOF Repair Data on 12 Patients with Pulmonary Regurgitation after Repair of Tetralogy of Fallot Patient Age at Pulmonary Valve Replacement Interval from Tetralogy Previous Operations Valve Size and Type" No. (yr) Repair and Other Lesions (mm) % 5 2% Yr 4 Yr 8 mo 4 Y' 2% yr 4 Yr 9% yr 11 yr 1% yr 10 yr 7 Y' 4% mo Bilateral Blalock-Taussig shunts when 3 and 4 years old; three previous operations on pulmonary arteries for stenosis Pulmonary hypertension, mild tricuspid insufficiency Pulmonary hypertension from bronchopulmonary dysplasia, bicuspid pulmonary valve Distal pulmonary stenosis, large aneurysm of outflow tract Bicuspid pulmonary valve Left pulmonary artery stenosis (repaired at time of PVR) Mild tricuspid regurgitation Blalock-Taussig shunt at birth; massive ascites and cardiac cachexia, tricuspid insufficiency (treated with TVR at time of PVR), left pulmonary artery stenosis (repaired at time of PVR) Blalock-Taussig shunt in first year of life, aortopulmonary window at age 4 for persistent small pulmonary arteries; distal right pulmonary artery stenosis, right ventricular outflow aneurysm... Tricuspid regurgitation (tricuspid annuloplasty at time of PVR) Atrial septostomy at 4 days of age for TAPVR (repaired at time of tetralogy repair); bicuspid pulmonary valve, severe pulmonary hypertension, tricuspid insufficiency 25, Bjork-Shiley 27, Ionescu-Shiley 21, Ionescu-Shiley 23, Ionescu-Shiley 21, Ionescu-Shiley 23, Carpentier-Edwards 23, Carpentier-Edwards 23, Carpentier-Edwards 27, Ionescu-Shiley 27, Ionescu-Shiley 23, Ionescu-Shiley 17, Bjork-Shiley "Bjork-Shiley mechanical valve; Ionescu-Shiley bovine pericardial valve; Carpentier-Edwards porcine valve. PVR = pulmonary valve replacement; TVR = tricuspid valve replacement; TAPVR = total anomalous pulmonary venous return. had a major ventricular septa1 defect. Five patients had distal pulmonary artery stenoses, and 3 additional patients had pulmonary hypertension (Fig 1). Six patients had tricuspid regurgitation. Although records are not complete since only 4 of the 12 patients had the initial tetralogy repair at our institution, available information in- dicates that at least 10, and possibly all, of the 12 patients had transannular patching in the initial repair. In at least 3 patients, a bicuspid pulmonary valve was seen at initial repair. Three patients had received a total of five systemicpulmonary artery shunts (four Blalock-Taussig shunts and one aortopulmonary window) prior to initial repair.

3 686 The Annals of Thoracic Surgery Vol 36 No 6 December 1983 Fig 1. Angiogram (injection of main pulmonary artery) from 4%-year-old patient with distal stenosis of the pulmonary artery and a large aneu rysm of the main pulmonary artery, both contributing to pulmonary regurgitation 4 years after repair of tetralogy of Fallot. Surgical Technique Through a median sternotomy, minimal dissection is done for adequate exposure of cannulation sites and the right ventricular outflow tract. Cardiopulmonary bypass is established with aortic and usually single atrial or occasionally bicaval cannulation. During moderate hypothermia and hemodilution, the heart is fibrillated and aortic cross-clamping is not required. A longitudinal incision is made through the previous right ventricular outflow tract patch and extended into the main pulmonary artery (Fig 2). The patch and any aneurysmal outflow tract tissue are excised. Pulmonary valve tissue may be excised. In many of the patients, the main pulmonary artery was sufficiently dilated that a prosthetic valve of adequate size could be inserted at the pulmonary annulus posteriorly and secured to the thickened wall of the pulmonary artery anteriorly (Fig 3). A triangular-shaped patch was used to close the defect in the right ventricle below the sewing ring of the prosthetic valve. In some patients, aneurysmal dilatation of the outflow tract and main pulmonary artery was handled best by reducing the size of the pulmonary artery by a modified 2-plasty. Y tract patch C D Fig 2. Pulmlonary valve replacement is begun with (A) an incision in the original transannular patch. The incision is continued into the main pulmonary artery. (B) The patch is excised and a prosthetic valve secured to the native annulus posteriorly with simple interrupted sutures. (C) A new outflow tract patch is sewn with a running suture to the pulmonary artery. (D) The prosthetic valve is secured anteriorly to the patch with interrupted horizontal mattress sutures, and patch closure of the right ventricular outflow tract is completed. In the patients in whom the pulmonary artery and right ventricular outflow tract were not of adequate (diameter to allow placement of an adequate-sized prosthesis, a new outflow tract patch was used to enlarge the pulmonary annulus. The prosthetic valve was sutured posteriorly to the native annulus with simple interrupted sutures and anteriorly to the outflow tract patch with horizontal mattress sutures, a technique similar to that for placement of a prosthetic valve in an enlarged left ventricular outflow tract 171. The anastomosis of the outflow tract patch to the right ventricle was completed during rewarming with the heart beating in all patients. In 1 patient a tricuspid valve replacement and a patch angioplasty of the left pulmonary artery were performed during the same operation. In another patient a tricuspid annuloplasty was done. In 1 patient a stenosis of the left pulmonary artery also was repaired with extension of

4 687 Misbach, Turley, and Ebert: Pulmonary Valve Replacement after TOF Repair C Fig 3. (A) Technique for pulmonary valve replacement is modified for aneurysmal main pulmonary arte ry. (B) The original patch is excised, and the apex of the defect in the pulmonary artery is pulled inferiorly to allow the prosthetic valve to be sutured directly to the wall of the pulmonary artery anteriorly. (C) The defect remaining in the right ventricular outfrow tract is closed with a triangularshaped patch. the right ventricular outflow tract patch into the left pulmonary artery. Results There have been no deaths. All 12 patients have had hemodynamic improvement by elimination of pulmonary regurgitation. Cardiopulmonary bypass averaged 69 minutes (range, 30 to 155 minutes). Aortic cross-clamping was not used. The youngest patient received a 17 mm Bjork- Shiley valve; all others received valves ranging from 21 to 27 mm in size. Mechanical valves were used in 2 patients and tissue valves in 10. Progressive right ventricular failure has been halted in all patients except 1 who did not achieve sustained relief of symptoms. This patient had severe tricuspid regurgitation as well as severe pulmonary regurgitation when pulmonary valve replacement was performed, and had undergone three previous patch angioplasty procedures for left and right pulmonary artery stenoses in the 7 years following initial tetralogy repair. Tricuspid valve replacement was performed 1Y2 years after pulmonary valve replacement, and the patient has done well subsequently. One other patient required an additional operation after pulmonary valve replacement; this was for pacemaker lead changes. All patients had relief of symptoms after pulmonary valve replacement except the 1 who required subsequent tricuspid valve replacement to achieve a satisfactory functional result. Repeat cardiac catheterization has not been performed routinely. However, because of the known high incidence of early calcification of heterograft valves in young patients [8,9], these patients are followed carefully for signs of valve failure. There have been no known instances of thromboembolism, and in the short-term follow-up available at this time (5 months to 3 years), there have been no instances of valve calcification or degeneration. Comment Since most patients can tolerate pulmonary regurgitation after repair of tetralogy of Fallot, pulmonary valve replacement has been performed only rarely in the past. Favorable experience with pulmonary valve insertion in the repair of tetralogy of Fallot with absent pulmonary valve [lo, 111 has led us to become more aggressive with pulmonary valve replacement in the treatment of patients with previous tetralogy repair in whom progressive right ventricular failure has developed. When pulmonary regurgitation is massive or when it is associated with other contributing causes to right ventricular failure, progressive right ventricular dilation can occur. In many of these patients tricuspid valve insufficiency also develops, and this may accelerate deterioration in functional status We believe that there is a need for at least one competent valve on each side of the heart to prevent progressive deterioration. If right ventricular diastolic volume can be kept smaller after pulmonary valve replacement, then tricuspid insufficiency may remain stable or regress. However, if pulmonary valve regurgitation leads to more and more right ventricular dilatation, worsening of tricuspid regurgitation can be expected. Tricuspid valve replacement, on the other hand, cannot necessarily be expected to help stabilize pulmonary valve regurgitation.

5 688 The Annals of Thoracic Surgery Vol 36 No 6 December 1983 Therefore, in most patients with pulmonary regurgitation and tricuspid regurgitation, we choose to replace the pulmonary valve preferentially. In some patients with massive tricuspid as well as pulmonary regurgitation, replacement of both valves may be needed. This was true in 1 patient in whom both valves were replaced at the same operation and in the patient who required tricuspid valve replacement 1 Yz years after pulmonary valve replacement. With the known early failure of porcine heterografts in children, it also may be wise to consider that any gradient developing across a prosthetic valve probably would be better handled by the right ventricle when the valve is in the pulmonary position than by the right atrium when the valve is in the tricuspid position. The relative frequency of severe pulmonary regurgitation after repair of tetralogy is difficult to know from this group of patients, since 8 of the 12 had primary repairs performed at other institutions. Fuster and associates [3] reported a 1% incidence of disability from pulmonary regurgitation and a 5% incidence of cardiomegaly from pulmonary regurgitation in long-term fol- Iow-up. Many authors have discussed the desirability of avoiding transannular patches whenever possible without leaving residual obstruction, both for obtaining a lower hospital mortality and for obtaining the best long-term functional result. The present report cannot shed light on the question of how to make the compromise between residual stenosis and pulmonary regurgitation [4-61. However, it does indicate the need to follow more carefully those patients who receive an outflow tract patch across the pulmonary annulus, and it does offer a method of treatment that can help to preserve right ventricular function in patients in whom medical treatment is not sufficient. Pulmonary valve replacement can be performed with low risk because no new ventriculotomy is needed: the pulmonary annulus can be opened through the previous outflow tract patch. Aortic cross-clamping is not required, and this can prevent further insult to the ventricle. We have a large experience with replacing right ventricle-pulmonary artery conduits. This procedure is similarly well tolerated, since no aortic cross-clamping and no new ven- triculotomy are needed. There is also less risk of conduction problems after pulmonary valve replacement than after other types of valve replacement. Many methods of reconstructing the right ventricular outflow tract have been used. In addition to an outflow tract patch that may extend across the pulmonary annulus to relieve stenosis, surgeons have used heterologous or homologous valves with the corresponding outflow root [13], valved prosthetic conduits [14], a valved conduit incorporated into the right ventricular outflow tract [15, 161, a monocusp patch [17, 181, and pulmonary valve insertion under a right ventricular outflow tract patch [19]. The advantages of pulmonary valve insertion under an outflow tract patch include the elimination of pulmonary regurgitation (not possible with an outflow tract patch alone and more reliably than with a monocusp patch) and the ability to insert a larger valve with a smaller gradient and with less chance of retrosternal compression than is possible with valved conduits. Laks and colleagues [19] reported these advantages with pulmonary valve insertion in patients with previous repair of tetralogy, patients with absent pulmonary valve syndrome, and patients with pulmonary atresia. Of their 6 patients who underwent reoperation after tetralogy repair, only 1 had pulmonary and tricuspid regurgitation as the major indication. Idriss and co-workers [20] discussed the use of prosthetic pulmonary valves after previous repair of tetralogy in 7 patients when other causes of right ventricular failure were present, such as stenosis of a pulmonary artery branch or pulmonary hypertension. Other series have not reported pulmonary valve replacement for pulmonary regurgitation alone. Among the 22 patients undergoing late right heart reconstructive operations after repair of tetralogy in the study of Miller and colleagues [21], 9 had orthotopic pulmonary valve replacement. Nineteen of the 22 patients had systolic gradients across the right ventricular outflow tract of 40 mm Hg or more, and 13 gradients were greater than 70 mm Hg. Pulmonary regurgitation was not listed among the eight individual anatomical lesions responsible for symptomatic deterioration and late reoperation, although

6 689 Misbach, Turley, and Ebert: Pulmonary Valve Replacement after TOF Repair 5 patients were shown in the category of right ventricular outflow tract aneurysm or pulmonary artery aneurysm. The authors suggested that earlier valve replacement may be indicated in selected patients to provide a more durable reconstruction. We think that when other correctable lesions such as residual outflow tract obstruction or residual ventricular septa1 defect are present, they should be repaired [12, 21-23]. However, in those patients in whom no other surgically correctable lesion is present, attention should be focused on repairing pulmonary regurgitation. This may include patients with very peripheral stenosis of a pulmonary artery branch, patients with pulmonary vascular disease resulting in pulmonary hypertension, and patients with poor right ventricular contractility. This may also include patients who have massive pulmonary regurgitation and development of aneurysmal pulmonary arteries. These patients may behave similarly to those with absent pulmonary valve syndrome who tolerate severe pulmonary regurgitation poorly. When pulmonary regurgitation is symptomatic, pulmonary valve replacement offers relief. However, since pulmonary regurgitation is usually well tolerated, insertion of a pulmonary valve in asymptomatic patients does not seem to be indicated. This is particularly true for children, because the longevity of tissue valves is especially limited and anticoagulation of mechanical valves is difficult. As longer follow-up of patients with previous repair of tetralogy becomes available, we may be faced with a question similar to that of proper timing of aortic valve replacement in adults who have asymptomatic aortic regurgitation. Some of these patients will have high right ventricular pressures, and the development of cardiomegaly may precede the development of symptoms. Serial exercise studies [6] may help to determine which patients should undergo pulmonary valve replacement and when this surgical intervention should be performed. Echocardiography may prove to be a useful tool for evaluating right ventricular and right atrial size, detecting when tricuspid regurgitation begins, and determining when cardiac catheterization is indicated. The difficult decision of balancing the risk of reoperation for repeated valve replacement against the risk of allowing cardiomegaly to progress is a decision likely to be faced more frequently in the years ahead. In patients in whom symptoms of right heart failure are progressive and not responsive to medical management, pulmonary regurgitation as a primary cause or substantial contributing cause should be investigated carefully. Such regurgitation is a component of right heart failure that is correctable by pulmonary valve replacement. The placement of a prosthetic valve in the pulmonary position under a right ventricular outflow patch allows use of a larger valve than is possible with valved conduits, relieves any residual gradients, and eliminates regurgitation. This operation can be performed with low risk and can prevent further deterioration of right ventricular function. We thank Laurel Schaubert for preparing the illustrations and Ms. Peggy Aspen for helping prepare the manuscript. References 1. Bender HW, Austen WG, Ebert PA, et al: Experimental pulmonic regurgitation. J Thorac Cardiovasc Surg 45:451, Collins NP, Braunwald E, Morrow AG: Isolated congenital pulmonic regurgitation: diagnosis by cardiac catheterization and angiography. Am J Med 28:159, Fuster V, McGoon DC, Kennedy MA, et al: Longterm evaluation (12 to 22 years) of open heart surgery for tetralogy of Fallot. Am J Cardiol 46:635, Kirklin JW, Blackstone EH: Editorial on papers by Naito, Wessel, and their colleagues. J Thorac Cardiovasc Surg 80:594, Naito Y, Fujita T, Manabe H, Kawashima Y: The criteria for reconstruction of right ventricular outflow tract in total correction of tetralogy of Fallot. J Thorac Cardiovasc Surg 80:574, Wessel HU, Cunningham WJ, Paul MH, et al: Exercise performance in tetralogy of Fallot after intracardiac repair. J Thorac Cardiovasc Surg 80:582, Misbach GA, Turley K, Ullyot DJ, Ebert PA: Left ventricular outflow enlargement by the Konno procedure. J Thorac Cardiovasc Surg 84:696, Geha AS, Laks H, Stansel HC, et al: Late failure of porcine valve heterografts in children. J Thorac Cardiovasc Surg 78:351, Williams DB, Danielson GK, McGoon DC, et al:

7 690 The Annals of Thoracic Surgery Vol 36 No 6 December 1983 Porcine heterograft valve replacement in children. J Thorac Cardiovasc Surg 84:446, Ilbawi MN, Idriss FS, Muster AJ, et al: Tetralogy of Fallot with absent pulmonary valve. J Thorac Cardiovasc Surg 81:906, Mavroudis C, Turley K, Stanger P, Ebert PA: Surgical management of tetralogy of Fallot and absent pulmonary valve. J Cardiovasc Surg (in press, 1983) 12. Rocchini AP, Rosenthal A, Freed M, et al: Chronic congestive heart failure after repair of tetralogy of Fallot. Circulation 56:305, Ross DN, Somerville J: Correction of pulmonary atresia with a homograft aortic valve. Lancet 2:1446, McGoon DC, Rastelli GC, Wallace RB: Discontinuity between the right ventricle and pulmonary artery: surgical treatment. Ann Surg 172: 680, Doetsch N, Schramm G, Hanke J, Reidemeister JC: Conduit-integration in correction of right ventricular outflow obstruction. Thorac Cardiovasc Surg 28:441, Laks H, Marin-Garcia J, Willman VL: In situ placement of a valved conduit at the pulmonary annulus. J Thorac Cardiovasc Surg 74:640, Ionescu MI, Tandon AP, Macartney FJ: Longterm sequential hemodynamic evaluation of right ventricular outflow tract reconstruction using a valve mechanism. Ann Thorac Surg 27:426, Trusler GA, Iyengar SR, Mustard WT: Reconstruction of the pulmonary valve and outflow tract. J Thorac Cardiovasc Surg 65:245, Laks H, Hellenbrand WE, Kleinman CS, et al: Patch reconstruction of the right ventricular outflow tract with pulmonary valve insertion. Circulation 64:Suppl 2:154, Idriss FS, Markowitz A, Hitsashi N, et al: Insertion of Hancock valve for pulmonary valve insufficiency in previously repaired tetralogy of Fallot (abstract). Circulation 53:Suppl 2:100, Miller DC, Rossiter SJ, Stinson EB, et al: Late right heart reconstruction following repair of tetralogy of Fallot. Ann Thorac Surg 28:239, Castaneda AR, Sade RM, Lamberti J, Nicoloff DM: Reoperation for residual defects after repair of tetralogy of Fallot. Surgery 76:1010, Donahoo JS, Brawley RK, Gott VL, Haller JA: Reoperation after total correction of tetralogy of Fallot. J Thorac Cardiovasc Surg 68:466, 1974 Discussion DR. HILLEL LAKS (Los Angeles, CA): I thank the Society for the privilege of discussing this fine paper and the authors for the opportunity of seeing their manuscript. I congratulate them on an outstanding series. The indications for pulmonary valve replacement remain controversial. The authors have reported their experience with patients in whom the indication for pulmonary valve replacement was severe progressive right ventricular failure following repair of tetralogy of Fallot. My colleagues and I agree with this indication and also with the preference of Dr. Misbach's group to replace the pulmonary valve and, if indicated, to perform a tricuspid annuloplasty when both pulmonary regurgitation and tricuspid regurgitation are present. In general, we have used the de Vega annuloplasty. We believe that in addition to these redo operations, pulmonary valve replacement should be performed primarily in patients with complex tetralogy of Fallot. Such patients include those with distal pulmonary stenosis or single pulmonary artery and those with pulmonary hypertension due to pulmonary vascular disease. It is interesting that in 8 of the 12 patients reported by Misbach and associates there was either distal pulmonary stenosis or pulmonary hypertension present at the initial operation. Whenever possible we prefer to use a valve beneath an outflow patch rather than a valved conduit. There is less room behind the sternum for a conduit, and a much larger valve can be placed in the outflow tract beneath a patch. We place the valve down low in the outflow tract based posteriorly on the crista supraventriciularis to enable insertion of an even larger valve. Using this technique, we were able to insert a 21 mm poircine valve in an infant weighing 8 kg. One patient with complex tetralogy of Fallot in whom we believed that primary pulmonary valve insertion was indicated had virtual pulmonary atresia, a previous; Blalock-Taussig shunt with a small left pulmonary artery, and a previous Glenn shunt with the beginning of fistula formation in the right lung. We used Gore-Tex grafts to reestablish continuity of the superior vena cava and right atrium and of the right and main pulmonary arteries. A 27 mm porcine valve was inserted as part of the primary operation. Another such patient was a 12-year-old boy who had previously undergone insertion of a homograft conduit with a Dacron graft to the right pulmonary artery, which thrombosed. The anterior wall of the homograft was removed together with the calcified valve, and a Dacron patch was inserted with a 27 mm porcine valve in the outflow tract. A Gore-Tex graft was placed from the patch distal to the valve to the right pulmonary artery, which was patent in the hilum of the lung. The other advantage of the valve beneath the patch is that it prevents the possibility of pseudointimal ingrowth, which has been reported in conduits resulting in obstruction. I ask Dr. Misbach to comment on the methods of myocardial protection used by his group. We have tried to avoid perfusion of the fibrillating heart and have preferred to use cardioplegia even in operations

8 691 Misbach, Turley, and Ebert: Pulmonary Valve Replacement after TOF Repair on the right side of the heart. I wonder if Dr. Misbach and his colleagues had any problems postoperatively with low output state. DR. MISBACH: I thank Dr. Laks for his comments and also for reemphasizing the advisability of replacing the pulmonary valve in preference to the tricuspid valve, although, of course, both may be required in some patients. An additional consideration is that as degeneration and calcification of some of the heterograft valves occur, the right ventricle may be able to tolerate stenosis of a valve in the pulmonary position better than the right atrium can handle stenosis across a valve in the tricuspid position. To answer Dr. Laks s question about myocardial protection, we have thought that in the absence of coronary stenoses, perfusion of the fibrillating heart probably is better than no perfusion at all. With the patient under moderate hypothermia and hemodilution, we fibrillate the heart for a portion of the procedure and leave it beating for the last portions when the outflow tract patch is being completed. We have not had difficulties with low cardiac output postoperatively. Notice from the North American Transplant Coordinators Organization Organ Donor Line Available to Health Professionals The nation s first toll-free telephone number for physicians, nurses, and other health professionals with questions about a potential organ donor has been based at the University of Pittsburgh. The number will assist health professionals by providing urgently needed information for a donor and referring the caller to his or her local procurement organization. The phone number, restricted to doctors, nurses, and other health professionals, is (800) 24-DONOR. The number operates 24 hours a day, 365 days a year. It is a service of the North American Transplant Coordinators Organization (NATCO) and part of its attempts to expand efforts to match available organs with those people waiting for a transplant. NATCO is the professional association of individuals responsible for organ procurement in hospitals. According to Donald W. Denny, director of organ procurement for the University of Pittsburgh, there are 110 organ procurement centers in this country, but often doctors and health professionals do not know whom to contact locally when a donor is identified. The new number provides information on the organ needs of the major transplant institutions in the United States and Canada. It includes information on kidneys, hearts, livers, lungs, pancreases, and heart/lung combinations. The general public can make inquiries about organ donations through DONORS-7 ( ).