The Damus-Fontan Procedure John J. Lamberti, MD, Richard D. Mainwaring, MD, J. Deane Waldman, MD, Lily George, MD, James W. Mathewson, MD, Robert L. Spicer, MD, and Stanley E. Kirkpatrick, MD Divisions of Cardiac Surgery and Pediatric Cardiology, Children’s Hospital and Health Center, San Diego, California
The Damus-Kaye-Stansel operation is a useful technique for the treatment of complex cyanotic congenital heart disease when there is obstruction between the systemic ventricle and the aorta. Modifications of the technique include transection of the aorta and the pulmonary artery, anastomosis of the contiguous aortic and pulmonary walls, and connection of the distal aorta to the perimeter of the new bivalved proximal great artery. In addition, the bidirectional cavopulmonary shunt tech-
nique can be used with or without the Fontan procedure. Six patients underwent a Damus-Fontan operation, and all survived. Two patients underwent the Damuscavopulmonary shunt (hemi-Fontan) procedure, and 1 survived. The postoperative status of the 7 survivors is good to excellent. Follow-up ranges from 2 months to 7% years.
A
tion and pulmonary artery banding as an infant. He was seen at 1 year of age with severe right ventricular hypertension, elevation of pulmonary artery pressure, and a small, poorly functioning left ventricle. The other patient was seen with tricuspid atresia, transposition of the great arteries, and a restrictive ventricular septal defect at 11 months of age. Initially, pulmonary artery banding and repair of coarctation of the aorta were performed. The Damuscavopulmonary shunt procedure was performed 2 months later.
nastomosis of the proximal main pulmonary artery to the side of the aorta to achieve unobstructed blood flow from the left ventricle to the aorta was suggested by Dr Paul Damus in 1973 [l].Stansel [2] and Kaye [3] also described this approach for the treatment of complex cyanotic congenital heart disease. We [4] have previously reported our experience with the Damus-Kaye-Stansel procedure, here referred to as the Damus procedure. This report provides long-term follow-up of the original patients with single ventricle and expands the discussion of the technical modifications used in our institution. In addition, the bidirectional cavopulmonary shunt [5,6] can be used with the Damus procedure to provide excellent palliation for patients with single ventricle.
Material and Methods Patient Population Six patients with univentricular hearts underwent the Damus-Fontan procedure [4]. Three patients had tricuspid atresia with transposition of the great arteries and a restrictive ventricular septal defect. One patient had double-outlet right ventricle, mitral atresia, and subaortic stenosis. Two patients had double-inlet left ventricle and transposition of the great arteries with restrictive ventricular septal defect. All patients had had prior pulmonary artery banding. Two patients underwent the Damus-cavopulmonary shunt operation for palliation of complex congenital heart defects [7]. A patient born with a variant of the hypoplastic left heart syndrome had undergone repair of coarctaAccepted for publication May 15, 1991.
Dr Waldman’s current address is Division of Pediatric Cardiology, The University of Chicago Medical Center, Wyler Children’s Hospital, 5841 S Maryland Ave, Chicago, IL 60637. Address reprint requests to Dr Lamberti, 8008 Frost St, Suite 400, San Diego, CA 92123.
0 1991 by The Society of Thoracic Surgeons
(Ann Thorac Surg 1991;52:676-9)
Operative Technique In older infants and children undergoing the DamusFontan procedure, continuous hypothermic cardiopulmonary bypass is used. It is usually possible to free up and mobilize the aortic arch beyond the level of the innominate vein. Cannulation on the inner curvature of the aortic arch allows placement of the cross-clamp just proximal to the innominate artery; thus continuous perfusion of the innominate artery and other arch vessels is possible while the repair is accomplished. In infants, deep hypothermia and circulatory arrest may be necessary to provide adequate access to the side of the ascending aorta. If hypoplasia of the proximal arch is present, a gusset of homograft can be used, as in the Norwood procedure [8]. Venous cannulation is adapted to the planned operation. We usually place a right-angled, metal-tipped cannula in the superior vena cava, particularly when transection of the vena cava is planned. The inferior vena cava can be cannulated with an angled cannula or a straight, baskettipped cannula. In the original reports [l-31, transection of the pulmonary artery with anastomosis to the side of the aorta was recommended. We believe that the operation should be adjusted to provide the optimal connection between the proximal pulmonary artery and the aorta. When dense adhesions exist or if the band site is proximal, the main pulmonary artery may not easily reach the side of the 0003-4975/91/$3.50
Ann Thorac Surg 1991;52:67&9
CONGENITAL HEART LAMBERTI ET AL DAMUS-FONTAN PROCEDURE
677
Fig 1 . Modifications of the Damus procedure. ( A ) The aorta and the pulmonary artery are transected at the same level, the cephalad end of the aortic sinuses of Valsalva. ( B ) lncisions are made in the contiguous pulmonary and aortic walls, with special attention paid to the coronary ostia and the valve commissures. These walls are sewn together. (C) Early modification of the Damus operation to allow unobstructed flow into the ascending aorta without distortion of the pulmonary annulus (causing regurgitation). ( D ) Current adaptation of the Damus approach allows rapid anastomosis of the new (bivalved) single “artey” (see B ) to the ascending aorta. (€) Original Damus concept for comparison: end-to-side anastomosis of the pulmona y arte y to the aorta. (Reprinted from Waldman ID, Lamberti I], George L , et al. Experience with Damus procedure. Circulation 1988;78(Suppl 3):32-9; by permission of the American Heart Association, Inc.)
ascending aorta. A gusset of Dacron, pericardium, or homograft may be necessary to provide adequate egress for blood from the left ventricle to the aorta. Transection of the main pulmonary artery at the level of the band site allows complete removal of scar tissue and repair of the pulmonary arteries when necessary. The aorta can also be transected. This approach allows optimal exposure of the pulmonary artery confluence and of the semilunar valves (Fig 1). An incision is made in the adjacent sinuses of Valsalva, and the aorta and pulmonary artery are connected with continuous Prolene (Ethicon, Somerville, NJ) or absorbable suture. The distal aorta is then positioned over the new, bivalved “artery“ arising from the ventricular mass. The distal aorta is sutured to the bivalve with Prolene or absorbable suture in an alignment that minimizes obstruction to blood flow. The pulmonary artery can be tailored if necessary, and a gusset of patch material may be useful to complete the anastomosis.
Three of the 6 patients undergoing the Damus-Fontan procedure underwent transection of the aorta and main pulmonary artery, In the other 3 patients, the pulmonary artery was transected and sutured to the side of the ascending aorta. Patients undergoing the Damuscavopulmonary shunt procedure underwent transection of the main pulmonary artery with patch reconstruction of the distal pulmonary artery. The proximal pulmonary artery was then sutured to the side of the ascending aorta. In 1 of our 2 infant patients, deep hypothermia and circulatory arrest were employed, and a gusset of homograft was used to complete the aortopulmonary connection. Figure 2 depicts the exposure when the aorta, the main pulmonary artery, and the superior vena cava are transected. After transection, the aorta may be mobilized away from the distal pulmonary arteries. Distal pulmonary artery stenoses can be easily repaired with an appropriate patch, and a capacious anastomosis between the
678
CONGENITAL HEART LAMBERTI ET AL DAMUS-FONTAN PROCEDURE
Fig 2 . Operative technique for combined Damus-Fontan-cauopulmonary connection. The transected main pulmonary artery and aorta allow excellent exposure of the distal pulmonary artery confluence. Unobstructed connections can be achieved between the right atrium and the pulmonay artery and the combined proximal aorta and pulmonary artery. For clarity of representation, cannulas are not shown. This operation has always been done using continuous hypothermic cardiopulmonary bypass with direct cannulation of the superior uena caua at the innominate junction.
superior aspect of the right atrium and the undersurface of the pulmonary artery can be performed. Then the Damus connection can be completed. Finally, the Fontan connection can be accomplished with performance of a cavopulmonary anastomosis if appropriate. Myocardial preservation includes the use of multidose blood cardioplegia and core cooling. A cooling jacket is placed around the heart in all patients, and the anterior myocardial temperature is monitored continuously. Cardioplegia is repeated at 20- to 30-minute intervals with direct cannulation of the coronary ostia if necessary.
Results All 6 patients undergoing the Damus-Fontan procedure survived. Follow up ranges from 4 to 7% years. Each patient has satisfactory exercise tolerance, and no patient experiences fluid retention. Two patients have had recurrent episodes of supraventricular tachycardia. One is on a regimen of digoxin (Lanoxin; Burroughs Wellcome, Research Triangle Park, NC). The other has an epicardial DDD pacemaker for late-onset sick sinus syndrome association with amiodarone hydrochloride therapy. Four patients are arrhythmia free. None of the 6 patients has required reoperation for the Damus-Fontan connection.
Ann Thorac Surg 1991;52:67&9
Five of the 6 patients have undergone recatheterization. There are no gradients in the systemic venous circuit. One patient had an 8-mm gradient from the left ventricle to the ascending aorta. Three patients have trace to 1+ semilunar valve regurgitation. In 1 patient, a left ventricular apical conduit was placed to the descending aorta during infancy. This was left in position at the time of the DamUe-Fontan connection. Late-onset regurgitation through the porcine valved conduit developed. At the age of 7 years, 3 years after the Damus-Fontan connection, the patient underwent percutaneous umbrella occlusion of the conduit. Complete occlusion of the apical conduit was achieved, and the patient has remained well since that time. Two patients underwent the Damus-cavopulmonary shunt operation [7]. The 1 with a variant of hypoplastic left heart syndrome died on the operating table. The preoperative pulmonary artery pressure was 28/20 mm Hg in the right pulmonary artery and 28/16 mm Hg in the left pulmonary artery. Average pulmonary artery pressure was about 22 mm Hg. Adequate oxygenation could not be achieved at the completion of the operation despite elevation of the superior vena cavdpulmonary artery pressure to 25 mm Hg. We concluded that the patient had elevated pulmonary vascular resistance and that adequate pulmonary blood flow could not be achieved with a cavopulmonary connection. The cavopulmonary shunt was taken down, and a systemic pulmonary artery shunt was implanted. The patient still could not be weaned from bypass because of poor myocardial function. The other patient, who had tricuspid atresia with transposition of the great arteries, is doing well 2 months postoperatively. The resting oxygen saturation is 0.80. The patient is on a regimen of maintenance digoxin and Aldactazide (spironolactone with hydrochlorothiazide; G.D. Searle & Co, Chicago, IL) therapy.
Comment The Damus-Kaye-Stansel procedure, here referred to as the Damus procedure, is a useful technique for repair or palliation of infants and children born with complex congenital heart defects. The operation provides a means to bypass obstruction to systemic blood flow without the need of complex intracardiac baffles or extensive intracardiac muscle resection. The risk of heart block associated with this connection should be negligible. Despite this, prior reports [9-111 have indicated a relatively high mortality for this operation. In addition, the development of the coronary switch procedure (anatomical repair of transposition) has reduced the total number of candidates for the Damus operation. Nonetheless, patients born with obstruction to systemic output because of a single ventricle and obstructive bulboventricular foramen, patients born with two ventricles and transposition of the great arteries with subaortic stenosis, or patients born with hypoplastic left heart syndrome with a small but inadequate left ventricle are still candidates for the Damus procedure. Although an obstructive bulboventricular foramen can be enlarged surgically [12], this procedure
CONGENITAL HEART LAMBERTI ET AL DAMUS-FONTAN PROCEDURE
Ann Thorac Surg 1991;52: 6 7 6 9
carries some risk of complete heart block, and there is always the possibility of inadequate resection. The Damus procedure is especially applicable for patients in whom the Fontan connection is planned, because it assures a nonobstructed systemic outlet with minimal possibility of myocardial damage. Intracardiac repair in patients born with transposition of the great arteries and subaortic stenosis is possible, although the risk is increased. When complex baffles are used for the intraventricular repair, anatomical repair with concomitant resection of obstructing muscle or tissue may not be as safe as the Damus-Fontan procedure. Some authors [lo, 131 have emphasized that pulmonary artery banding exaggerates subaortic stenosis and have recommended an early Damus shunt type of procedure. We [4] believe that pulmonary artery banding carries lower risk than a primary Damus shunt operation during the neonatal period. Early debanding after the pulmonary resistance has fallen to normal levels permits use of the cavopulmonary shunt to provide pulmonary blood flow after the Damus procedure. Thus, pulmonary artery banding followed by the Damuscavopulmonary shunt operation should convert patients with a single ventricle to the optimal physiological status during the first year of life. The Damus procedure eliminates afterload, and the cavopulmonary shunt provides increased pulmonary blood flow without volume load of the single ventricle. In summary, the Damus procedure provides a straightforward, safe method for relieving obstruction to systemic blood flow in complex forms of congenital heart disease. For patients with single ventricle, the Damus procedure seems ideal. For patients born with two functional ventricles, alternative surgical procedures may be equally attractive. The surgeon can determine the appropriate surgical procedure at the time of operation when the anatomy is clearly defined. Medium-term follow-up of our patients indicates satisfactory growth of the anastomosis and minimal progression of semilunar valve insufficiency. Long-term follow-up will demonstrate whether patients undergoing the Damus-Fontan procedure have the same natural history as patients undergoing the Fontan procedure for single ventricle with unobstructed systemic ventricular outlet.
679
References 1. Damus PS. Correspondence. Ann Thorac Surg 1975;20: 724-5. 2. Stansel HC Jr. A new operation for d-loop transposition of the great vessels. Ann Thorac Surg 1975;19:565-7. 3. Kaye MP. Anatomic correction of transposition of the great arteries. Mayo Clin Proc 1975;50:63840. 4. Waldman JD, Lamberti JJ, George L, et al. Experience with Damus procedure. Circulation 1988;78(Suppl 3):32-9. 5. Lamberti JJ, Spicer RL, Waldman JD, et al. The bidirectional cavopulmonary shunt. J Thorac Cardiovasc Surg 1990;lOO: 22-30. 6. Bridges ND, Jonas RA, Mayer JE, et al. Bidirectional cavopulmonary anastomosis as interim palliation for high-risk Fontan candidates: early results. Circulation 1990;82(Suppl 4):170-6. 7. Di Donato R, Di Carlo D, Giannico S, Marcelletti C. Palliation of complex cardiac anomalies with subaortic obstruction: new operative approach. J Am Coll Cardiol 1989;13:406-12. 8. Norwood WI, Lang P, Hansen DD. Physiologic repair of aortic atresia-hypoplastic left heart syndrome. N Engl J Med 1983;308:263-5. 9. Ceithaml EL, Puga FJ, Danielson GK, McGoon DC, Ritter DG. Results of the Damus-Stansel-Kaye procedure for transposition of the great arteries and for double-outlet right ventricle with subpulmonary ventricular septa1 defect. Ann Thorac Surg 1984;38:433-7. 10. Rothman A, Lang P, Lock JE, Jonas RA, Mayer JE, Castaneda AR. Surgical management of subaortic obstruction in single left ventricle and tricuspid atresia. J Am Coll Cardiol 1987;lO: 4214. 11. Lin AE, Laks H, Barber G, Chin AJ, Williams RG. Subaortic obstruction in complex congenital heart disease: management by proximal pulmonary artery to ascending aorta end-to-side anastomosis. J Am Coll Cardiol 1986;7617-24. 12. Penkoske PA, Freedom RM, Williams WG, Trusler GA, Rowe RD. Surgical palliation of subaortic stenosis in the univentricular heart. J Thorac Cardiovasc Surg 1984;87: 767-81. 13. Freedom RM. The dinosaur and banding of the main pulmonary trunk in the heart with functionally one ventricle and transposition of the great arteries: a saga of evolution and caution. J Am Coll Cardiol 1987;10:427-9.
The Damus-Kaye-Stansel operation is a useful technique for the treatment of complex cyanotic congenital heart disease when there is obstruction between the systemic ventricle and the aorta. Modifications of the technique include transection of the aorta and the pulmonary artery, anastomosis of the contiguous aortic and pulmonary walls, and connection of the distal aorta to the perimeter of the new bivalved proximal great artery. In addition, the bidirectional cavopulmonary shunt tech-
nique can be used with or without the Fontan procedure. Six patients underwent a Damus-Fontan operation, and all survived. Two patients underwent the Damuscavopulmonary shunt (hemi-Fontan) procedure, and 1 survived. The postoperative status of the 7 survivors is good to excellent. Follow-up ranges from 2 months to 7% years.
A
tion and pulmonary artery banding as an infant. He was seen at 1 year of age with severe right ventricular hypertension, elevation of pulmonary artery pressure, and a small, poorly functioning left ventricle. The other patient was seen with tricuspid atresia, transposition of the great arteries, and a restrictive ventricular septal defect at 11 months of age. Initially, pulmonary artery banding and repair of coarctation of the aorta were performed. The Damuscavopulmonary shunt procedure was performed 2 months later.
nastomosis of the proximal main pulmonary artery to the side of the aorta to achieve unobstructed blood flow from the left ventricle to the aorta was suggested by Dr Paul Damus in 1973 [l].Stansel [2] and Kaye [3] also described this approach for the treatment of complex cyanotic congenital heart disease. We [4] have previously reported our experience with the Damus-Kaye-Stansel procedure, here referred to as the Damus procedure. This report provides long-term follow-up of the original patients with single ventricle and expands the discussion of the technical modifications used in our institution. In addition, the bidirectional cavopulmonary shunt [5,6] can be used with the Damus procedure to provide excellent palliation for patients with single ventricle.
Material and Methods Patient Population Six patients with univentricular hearts underwent the Damus-Fontan procedure [4]. Three patients had tricuspid atresia with transposition of the great arteries and a restrictive ventricular septal defect. One patient had double-outlet right ventricle, mitral atresia, and subaortic stenosis. Two patients had double-inlet left ventricle and transposition of the great arteries with restrictive ventricular septal defect. All patients had had prior pulmonary artery banding. Two patients underwent the Damus-cavopulmonary shunt operation for palliation of complex congenital heart defects [7]. A patient born with a variant of the hypoplastic left heart syndrome had undergone repair of coarctaAccepted for publication May 15, 1991.
Dr Waldman’s current address is Division of Pediatric Cardiology, The University of Chicago Medical Center, Wyler Children’s Hospital, 5841 S Maryland Ave, Chicago, IL 60637. Address reprint requests to Dr Lamberti, 8008 Frost St, Suite 400, San Diego, CA 92123.
0 1991 by The Society of Thoracic Surgeons
(Ann Thorac Surg 1991;52:676-9)
Operative Technique In older infants and children undergoing the DamusFontan procedure, continuous hypothermic cardiopulmonary bypass is used. It is usually possible to free up and mobilize the aortic arch beyond the level of the innominate vein. Cannulation on the inner curvature of the aortic arch allows placement of the cross-clamp just proximal to the innominate artery; thus continuous perfusion of the innominate artery and other arch vessels is possible while the repair is accomplished. In infants, deep hypothermia and circulatory arrest may be necessary to provide adequate access to the side of the ascending aorta. If hypoplasia of the proximal arch is present, a gusset of homograft can be used, as in the Norwood procedure [8]. Venous cannulation is adapted to the planned operation. We usually place a right-angled, metal-tipped cannula in the superior vena cava, particularly when transection of the vena cava is planned. The inferior vena cava can be cannulated with an angled cannula or a straight, baskettipped cannula. In the original reports [l-31, transection of the pulmonary artery with anastomosis to the side of the aorta was recommended. We believe that the operation should be adjusted to provide the optimal connection between the proximal pulmonary artery and the aorta. When dense adhesions exist or if the band site is proximal, the main pulmonary artery may not easily reach the side of the 0003-4975/91/$3.50
Ann Thorac Surg 1991;52:67&9
CONGENITAL HEART LAMBERTI ET AL DAMUS-FONTAN PROCEDURE
677
Fig 1 . Modifications of the Damus procedure. ( A ) The aorta and the pulmonary artery are transected at the same level, the cephalad end of the aortic sinuses of Valsalva. ( B ) lncisions are made in the contiguous pulmonary and aortic walls, with special attention paid to the coronary ostia and the valve commissures. These walls are sewn together. (C) Early modification of the Damus operation to allow unobstructed flow into the ascending aorta without distortion of the pulmonary annulus (causing regurgitation). ( D ) Current adaptation of the Damus approach allows rapid anastomosis of the new (bivalved) single “artey” (see B ) to the ascending aorta. (€) Original Damus concept for comparison: end-to-side anastomosis of the pulmona y arte y to the aorta. (Reprinted from Waldman ID, Lamberti I], George L , et al. Experience with Damus procedure. Circulation 1988;78(Suppl 3):32-9; by permission of the American Heart Association, Inc.)
ascending aorta. A gusset of Dacron, pericardium, or homograft may be necessary to provide adequate egress for blood from the left ventricle to the aorta. Transection of the main pulmonary artery at the level of the band site allows complete removal of scar tissue and repair of the pulmonary arteries when necessary. The aorta can also be transected. This approach allows optimal exposure of the pulmonary artery confluence and of the semilunar valves (Fig 1). An incision is made in the adjacent sinuses of Valsalva, and the aorta and pulmonary artery are connected with continuous Prolene (Ethicon, Somerville, NJ) or absorbable suture. The distal aorta is then positioned over the new, bivalved “artery“ arising from the ventricular mass. The distal aorta is sutured to the bivalve with Prolene or absorbable suture in an alignment that minimizes obstruction to blood flow. The pulmonary artery can be tailored if necessary, and a gusset of patch material may be useful to complete the anastomosis.
Three of the 6 patients undergoing the Damus-Fontan procedure underwent transection of the aorta and main pulmonary artery, In the other 3 patients, the pulmonary artery was transected and sutured to the side of the ascending aorta. Patients undergoing the Damuscavopulmonary shunt procedure underwent transection of the main pulmonary artery with patch reconstruction of the distal pulmonary artery. The proximal pulmonary artery was then sutured to the side of the ascending aorta. In 1 of our 2 infant patients, deep hypothermia and circulatory arrest were employed, and a gusset of homograft was used to complete the aortopulmonary connection. Figure 2 depicts the exposure when the aorta, the main pulmonary artery, and the superior vena cava are transected. After transection, the aorta may be mobilized away from the distal pulmonary arteries. Distal pulmonary artery stenoses can be easily repaired with an appropriate patch, and a capacious anastomosis between the
678
CONGENITAL HEART LAMBERTI ET AL DAMUS-FONTAN PROCEDURE
Fig 2 . Operative technique for combined Damus-Fontan-cauopulmonary connection. The transected main pulmonary artery and aorta allow excellent exposure of the distal pulmonary artery confluence. Unobstructed connections can be achieved between the right atrium and the pulmonay artery and the combined proximal aorta and pulmonary artery. For clarity of representation, cannulas are not shown. This operation has always been done using continuous hypothermic cardiopulmonary bypass with direct cannulation of the superior uena caua at the innominate junction.
superior aspect of the right atrium and the undersurface of the pulmonary artery can be performed. Then the Damus connection can be completed. Finally, the Fontan connection can be accomplished with performance of a cavopulmonary anastomosis if appropriate. Myocardial preservation includes the use of multidose blood cardioplegia and core cooling. A cooling jacket is placed around the heart in all patients, and the anterior myocardial temperature is monitored continuously. Cardioplegia is repeated at 20- to 30-minute intervals with direct cannulation of the coronary ostia if necessary.
Results All 6 patients undergoing the Damus-Fontan procedure survived. Follow up ranges from 4 to 7% years. Each patient has satisfactory exercise tolerance, and no patient experiences fluid retention. Two patients have had recurrent episodes of supraventricular tachycardia. One is on a regimen of digoxin (Lanoxin; Burroughs Wellcome, Research Triangle Park, NC). The other has an epicardial DDD pacemaker for late-onset sick sinus syndrome association with amiodarone hydrochloride therapy. Four patients are arrhythmia free. None of the 6 patients has required reoperation for the Damus-Fontan connection.
Ann Thorac Surg 1991;52:67&9
Five of the 6 patients have undergone recatheterization. There are no gradients in the systemic venous circuit. One patient had an 8-mm gradient from the left ventricle to the ascending aorta. Three patients have trace to 1+ semilunar valve regurgitation. In 1 patient, a left ventricular apical conduit was placed to the descending aorta during infancy. This was left in position at the time of the DamUe-Fontan connection. Late-onset regurgitation through the porcine valved conduit developed. At the age of 7 years, 3 years after the Damus-Fontan connection, the patient underwent percutaneous umbrella occlusion of the conduit. Complete occlusion of the apical conduit was achieved, and the patient has remained well since that time. Two patients underwent the Damus-cavopulmonary shunt operation [7]. The 1 with a variant of hypoplastic left heart syndrome died on the operating table. The preoperative pulmonary artery pressure was 28/20 mm Hg in the right pulmonary artery and 28/16 mm Hg in the left pulmonary artery. Average pulmonary artery pressure was about 22 mm Hg. Adequate oxygenation could not be achieved at the completion of the operation despite elevation of the superior vena cavdpulmonary artery pressure to 25 mm Hg. We concluded that the patient had elevated pulmonary vascular resistance and that adequate pulmonary blood flow could not be achieved with a cavopulmonary connection. The cavopulmonary shunt was taken down, and a systemic pulmonary artery shunt was implanted. The patient still could not be weaned from bypass because of poor myocardial function. The other patient, who had tricuspid atresia with transposition of the great arteries, is doing well 2 months postoperatively. The resting oxygen saturation is 0.80. The patient is on a regimen of maintenance digoxin and Aldactazide (spironolactone with hydrochlorothiazide; G.D. Searle & Co, Chicago, IL) therapy.
Comment The Damus-Kaye-Stansel procedure, here referred to as the Damus procedure, is a useful technique for repair or palliation of infants and children born with complex congenital heart defects. The operation provides a means to bypass obstruction to systemic blood flow without the need of complex intracardiac baffles or extensive intracardiac muscle resection. The risk of heart block associated with this connection should be negligible. Despite this, prior reports [9-111 have indicated a relatively high mortality for this operation. In addition, the development of the coronary switch procedure (anatomical repair of transposition) has reduced the total number of candidates for the Damus operation. Nonetheless, patients born with obstruction to systemic output because of a single ventricle and obstructive bulboventricular foramen, patients born with two ventricles and transposition of the great arteries with subaortic stenosis, or patients born with hypoplastic left heart syndrome with a small but inadequate left ventricle are still candidates for the Damus procedure. Although an obstructive bulboventricular foramen can be enlarged surgically [12], this procedure
CONGENITAL HEART LAMBERTI ET AL DAMUS-FONTAN PROCEDURE
Ann Thorac Surg 1991;52: 6 7 6 9
carries some risk of complete heart block, and there is always the possibility of inadequate resection. The Damus procedure is especially applicable for patients in whom the Fontan connection is planned, because it assures a nonobstructed systemic outlet with minimal possibility of myocardial damage. Intracardiac repair in patients born with transposition of the great arteries and subaortic stenosis is possible, although the risk is increased. When complex baffles are used for the intraventricular repair, anatomical repair with concomitant resection of obstructing muscle or tissue may not be as safe as the Damus-Fontan procedure. Some authors [lo, 131 have emphasized that pulmonary artery banding exaggerates subaortic stenosis and have recommended an early Damus shunt type of procedure. We [4] believe that pulmonary artery banding carries lower risk than a primary Damus shunt operation during the neonatal period. Early debanding after the pulmonary resistance has fallen to normal levels permits use of the cavopulmonary shunt to provide pulmonary blood flow after the Damus procedure. Thus, pulmonary artery banding followed by the Damuscavopulmonary shunt operation should convert patients with a single ventricle to the optimal physiological status during the first year of life. The Damus procedure eliminates afterload, and the cavopulmonary shunt provides increased pulmonary blood flow without volume load of the single ventricle. In summary, the Damus procedure provides a straightforward, safe method for relieving obstruction to systemic blood flow in complex forms of congenital heart disease. For patients with single ventricle, the Damus procedure seems ideal. For patients born with two functional ventricles, alternative surgical procedures may be equally attractive. The surgeon can determine the appropriate surgical procedure at the time of operation when the anatomy is clearly defined. Medium-term follow-up of our patients indicates satisfactory growth of the anastomosis and minimal progression of semilunar valve insufficiency. Long-term follow-up will demonstrate whether patients undergoing the Damus-Fontan procedure have the same natural history as patients undergoing the Fontan procedure for single ventricle with unobstructed systemic ventricular outlet.
679
References 1. Damus PS. Correspondence. Ann Thorac Surg 1975;20: 724-5. 2. Stansel HC Jr. A new operation for d-loop transposition of the great vessels. Ann Thorac Surg 1975;19:565-7. 3. Kaye MP. Anatomic correction of transposition of the great arteries. Mayo Clin Proc 1975;50:63840. 4. Waldman JD, Lamberti JJ, George L, et al. Experience with Damus procedure. Circulation 1988;78(Suppl 3):32-9. 5. Lamberti JJ, Spicer RL, Waldman JD, et al. The bidirectional cavopulmonary shunt. J Thorac Cardiovasc Surg 1990;lOO: 22-30. 6. Bridges ND, Jonas RA, Mayer JE, et al. Bidirectional cavopulmonary anastomosis as interim palliation for high-risk Fontan candidates: early results. Circulation 1990;82(Suppl 4):170-6. 7. Di Donato R, Di Carlo D, Giannico S, Marcelletti C. Palliation of complex cardiac anomalies with subaortic obstruction: new operative approach. J Am Coll Cardiol 1989;13:406-12. 8. Norwood WI, Lang P, Hansen DD. Physiologic repair of aortic atresia-hypoplastic left heart syndrome. N Engl J Med 1983;308:263-5. 9. Ceithaml EL, Puga FJ, Danielson GK, McGoon DC, Ritter DG. Results of the Damus-Stansel-Kaye procedure for transposition of the great arteries and for double-outlet right ventricle with subpulmonary ventricular septa1 defect. Ann Thorac Surg 1984;38:433-7. 10. Rothman A, Lang P, Lock JE, Jonas RA, Mayer JE, Castaneda AR. Surgical management of subaortic obstruction in single left ventricle and tricuspid atresia. J Am Coll Cardiol 1987;lO: 4214. 11. Lin AE, Laks H, Barber G, Chin AJ, Williams RG. Subaortic obstruction in complex congenital heart disease: management by proximal pulmonary artery to ascending aorta end-to-side anastomosis. J Am Coll Cardiol 1986;7617-24. 12. Penkoske PA, Freedom RM, Williams WG, Trusler GA, Rowe RD. Surgical palliation of subaortic stenosis in the univentricular heart. J Thorac Cardiovasc Surg 1984;87: 767-81. 13. Freedom RM. The dinosaur and banding of the main pulmonary trunk in the heart with functionally one ventricle and transposition of the great arteries: a saga of evolution and caution. J Am Coll Cardiol 1987;10:427-9.
