| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
|
|
|
|||||||
|
|||||||||
Ann Thorac Surg 1998;66:683-687
© 1998 The Society of Thoracic Surgeons
a Division of Cardiothoracic Surgery, University of California, San Francisco, California, USA
Address reprint requests to Dr Reddy, Division of Cardiothoracic Surgery, 505 Parnassus Avenue, M593, San Francisco, CA 94143-0118
Presented at the Workshop on "One and One-Half Ventricle Repairs," Gubbio, Italy, Dec 6–7, 1996.
Abstract
Background. Bidirectional cavopulmonary shunt and Fontan repair are now commonly performed in patients with a variety of forms of complex single ventricle, including those with anomalies of systemic, pulmonary, or systemic and pulmonary venous return. These anomalies are ideally dealt with during bidirectional cavopulmonary shunt, thereby minimizing the complexity of the eventual Fontan procedure.
Methods and Results. Between March 1990 and March 1997, 32 patients with functional single ventricle and anomalous pulmonary venous return underwent operation at our institution. Five of 25 patients who underwent neonatal palliation died in the early postoperative period, all of whom had obstructed anomalous pulmonary venous return. Twenty-one patients have undergone bidirectional cavopulmonary shunt, including 7 in whom this was the primary palliative procedure. There was one early and two late deaths after the bidirectional Glenn procedure, two in patients with asplenia syndrome and none in patients with previously obstructed pulmonary venous return. Seven patients have undergone Fontan completion, 5 with an extracardiac conduit. There was one early death and one take-down to a classic Glenn shunt, both in patients who did not undergo the extracardiac conduit Fontan operation.
Conclusions. Anomalous pulmonary venous return can significantly complicate the management of the single-ventricle patient, with the major impact on survival coming in the neonatal period. Palliation with the aim of performing an extracardiac conduit Fontan procedure allows greater latitude and more streamlined management in this group of patients.
Anomalies of pulmonary venous return can complicate management of the single-ventricle patient at any stage of palliation, whether it be primary neonatal palliation, bidirectional Glenn, or completion of the Fontan operation. The majority of patients with a complex single-ventricle anatomy and anomalous pulmonary venous return have heterotaxy syndrome with atrial isomerism, which may contribute to the impression that patients with anomalous pulmonary venous drainage have worse outcomes [1]. Nevertheless, there are many circumstances in which a more complicated clinical course and operative management can be attributed to the pulmonary venous anomalies per se [2, 3]. In the present article, we discuss our experience with anomalous pulmonary venous return in patients undergoing single-ventricle palliation. Because our preferred definitive palliation for the patient with a functional single ventricle is an extracardiac conduit Fontan operation, neonatal palliation and the bidirectional Glenn operation are undertaken with this end in mind [4]. In addition to its many other potential advantages, the extracardiac conduit Fontan operation can be applied in patients with the full range of pulmonary venous anomalies with little or no modification, which may facilitate not only the Fontan procedure itself, but neonatal palliation and bidirectional cavopulmonary shunt as well.
Patients and methods
Between January 1990 and February 1997, 32 patients with functional single ventricle and anomalies of pulmonary venous return underwent operation for staged palliation at our institution. Visceroatrial heterotaxy with atrial isomerism was present in 24 patients (78%): 17 had asplenia with right atrial isomerism and 7 had polysplenia with left atrial isomerism. Other primary diagnoses included hypoplastic left heart syndrome (n = 3), tricuspid atresia (n = 2), Ebstein’s anomaly (n = 1), and other forms of complex single ventricle (n = 2).
In addition to the standard classification according to drainage site, anomalies of pulmonary venous return were categorized as either (1) anomalous but not requiring special intervention at any stage of management or (2) anomalous and necessitating special intervention at some stage of palliation. Because our approach is to perform an extracardiac conduit Fontan operation in almost all single-ventricle patients, anomalies of pulmonary venous return not requiring intervention include all forms of cardiac anomalous drainage, such as drainage to the middle or systemic side of a common atrium. Most forms of high supracardiac and infracardiac anomalous drainage and all cases of obstructed anomalous pulmonary venous drainage require intervention, as do most cases of cardiac anomalous drainage when one and a half ventricle repair is planned. The distribution of types of anomalous pulmonary venous return is summarized in Table 1.
|
Results
Primary neonatal palliation
Twenty-five patients underwent primary neonatal palliation with a systemic–pulmonary artery shunt. Nine patients underwent repair of totally anomalous pulmonary venous return at primary palliation, all of whom had pulmonary venous obstruction diagnosed preoperatively by means of cross-sectional and Doppler echocardiography. In the 7 patients with obstructed return to a systemic vein, standard techniques of pulmonary venous to left atrial anastomosis were performed. In 1 of these patients, the pulmonary venous repair was the first operation performed, followed by placement of a systemic–pulmonary artery shunt 2 months later. In 2 patients with cor triatriatum (1 with hypoplastic left heart syndrome and the other with asplenia and subaortic obstruction), neonatal repair of obstructive cor triatriatum was performed as the primary procedure: in the patient with hypoplastic left heart a Norwood operation was performed 2 days later, and in the patient with asplenia a modified Damus-Kaye-Stansel anastomosis was performed at 3 months of age. In 2 patients with hypoplastic left heart syndrome and a levoatriocardinal vein carrying pulmonary venous blood to the left innominate vein [5], the anomalous vein was ligated and divided at the time of stage I Norwood operation.
There were five early deaths after primary palliation (20%), all in patients who had obstructed pulmonary venous return. One of these was a patient who underwent repair of obstructed totally anomalous pulmonary venous return at 1 day of age, then had a systemic–pulmonary arterial shunt placed along with augmentation of native (not anastomotic) left upper and lower pulmonary venous stenosis 2 months later. Two of the early deaths were in patients with hypoplastic left heart syndrome, and the other 3 were in patients who had asplenia with right atrial isomerism. Two survivors of primary palliation have not yet undergone subsequent stages of the single-ventricle palliation.
Bidirectional cavopulmonary shunt
Twenty-one patients underwent bidirectional cavopulmonary shunt, including 7 patients in whom this was the primary palliative procedure. Our experience with the bidirectional cavopulmonary shunt in patients with anomalous pulmonary venous return has been reported previously [4]. Nine patients had unobstructed anomalous pulmonary venous return to the middle or systemic side of a common atrium. In these patients, nothing was done to modify the anomalous pulmonary venous return. In 4 patients with anomalous pulmonary venous return to a left (n = 1) or right (n = 3) superior vena cava just craniad to the superior cavoatrial junction, the superior vena cava was divided for the bidirectional Glenn procedure sufficiently above the entrance of the pulmonary vein(s) to avoid pulmonary venous obstruction, and the superior vena caval stump was oversewn to allow drainage of the pulmonary venous blood into the left or right atrium, respectively. These techniques are not applicable if a subsequent lateral tunnel-type Fontan procedure is planned. In 5 patients supracardiac (n = 4) or infracardiac (n = 1) totally anomalous pulmonary venous return was repaired by standard techniques of pulmonary venous to left atrial anastomosis. In 2 patients with high supracardiac anomalous pulmonary venous return, the ascending vein was ligated and anastomosed either to the cardiac stump of a left superior vena cava that had been divided for a bidirectional Glenn operation, or to the tip of the right-sided (ie, systemic) atrial appendage.
Late pulmonary vein reoperation before Fontan completion was performed in 1 patient who had undergone repair of totally anomalous pulmonary venous return at 2 weeks of age at another institution and required repair of mild left and severe right pulmonary vein stenoses 5 months after a bidirectional Glenn operation. These stenoses were not noticed during the work-up for the bidirectional Glenn procedure, but they had probably been present, as they were caused by scarring at the site of anastomosis to the left atrium.
There was one early and two late deaths after the bidirectional Glenn procedure, two in patients with asplenia syndrome and one in a patient with another form of complex single ventricle, none of whom had obstructed pulmonary venous return. All three deaths were due to respiratory illnesses, and none were thought to be the consequence of the anomalous pulmonary venous return. These cases are presented in detail in a previous report [4].
Fontan operation
Seven patients have undergone Fontan completion. Five of these patients underwent extracardiac conduit Fontan operation. One patient, early in our experience, underwent attempted intracardiac conduit Fontan but this was taken down during the same operation and converted to an extracardiac conduit. Another early patient with polysplenia and interruption of the inferior vena cava, who had not undergone prior bidirectional cavopulmonary shunt, had a modified lateral tunnel Fontan procedure performed. The only early death after the Fontan operation was in a patient with asplenia syndrome and totally anomalous pulmonary venous return to a common atrium, who did not require pulmonary vein intervention at the time of primary palliation (which was a bidirectional Glenn procedure), but later had development of echocardiographic evidence of mild pulmonary venous obstruction and underwent unroofing of the pulmonary veins at Fontan completion 18 months after the Glenn procedure. This was the patient described above who initially had an intracardiac conduit Fontan operation performed, and she died on the second postoperative day after sustaining a cerebrovascular accident. In addition, the patient who underwent modified lateral tunnel Fontan operation had the Fontan taken down to a bidirectional Glenn circulation 3 days postoperatively.
Comment
Staged palliation culminating in a Fontan physiology has been increasingly applied to patients with a variety of complex single-ventricle anatomies, including those that occur with pulmonary venous anomalies. Although reports have addressed the issues of managing anomalous pulmonary venous drainage at primary palliation [3], bidirectional cavopulmonary shunt [4, 6], and Fontan operation [7–9], the overall impact of pulmonary venous anomalies on outcomes of staged palliation for functional single-ventricle lesions has not been well characterized [1, 2]. Typically, single-ventricle palliation involves neonatal placement of a pulmonary artery band or systemic–pulmonary artery shunt, followed by bidirectional Glenn anastomosis in midinfancy, and then completion of the modified Fontan circulation at several years of age. Thus, there are generally three operations at which management of anomalous pulmonary venous return must be considered. Optimizing the circulation in preparation for an ultimate Fontan procedure should be of high priority even in the earliest stages of single-ventricle palliation. This is especially true when pulmonary venous anomalies are present, as first- and second-stage procedures can facilitate straightforward techniques for managing the anomalous venous return at Fontan operation.
Most forms of anomalous pulmonary venous return in single-ventricle patients are unobstructed at the time of presentation. Nevertheless, pulmonary venous return must be evaluated completely with preoperative echocardiography, which is adequate to diagnose almost all forms of anomalous pulmonary venous return. Diagnosis of obstruction may be complicated in the setting of restrictive pulmonary blood flow, but the routine use of prostaglandins to maintain ductal patency in such patients in the current era makes this less of a concern than in the past. Moreover, certain forms of anomalous pulmonary venous return, such as those with infradiaphragmatic drainage, are typically obstructed and should be assumed to be so when identified in patients with reduced pulmonary blood flow. When obstruction is present, of course, it is necessary to correct the anomalous return immediately. Early mortality after neonatal palliation in heterotaxy patients with anomalous pulmonary venous return was 26% in a 10-year series at the Boston Children’s Hospital [3], and substantially higher in other reports [1, 2, 10]. In most series, mortality was higher among patients with obstruction. In our experience, obstruction of pulmonary venous return significantly complicated management of the single-ventricle patient, and all five early deaths after primary palliation were in patients with obstructed totally anomalous return. This is true not only for the more common patients with visceroatrial heterotaxy, but for those with other primary lesions as well, and especially for those with hypoplastic left heart syndrome, which was the case in 2 of our patients. In patients with lesions causing reduced pulmonary blood flow, increasing flow to the lungs by placing a shunt may unmask obstruction to pulmonary venous return [3, 9, 11]. Thus, it is of utmost importance to evaluate pulmonary venous anomalies after procedures to increase pulmonary blood flow, regardless of whether a pulmonary venous intervention has been performed. In several studies, the presence of pulmonary outflow obstruction in patients with heterotaxy and anomalous pulmonary venous return was associated with higher early mortality after primary palliation [1, 3].
Bidirectional cavopulmonary anastomosis is most often performed as a second-stage palliation, but can be employed as a primary palliative procedure early in infancy in select patients with balanced pulmonary blood flow [12]. We have previously reported our experience with bidirectional cavopulmonary anastomosis in patients with anomalies of venous return, and did not find any increased risk of death or Glenn failure relative to our entire cohort of patients undergoing bidirectional cavopulmonary anastomosis during the same time period [4]. As we described in that report, bidirectional cavopulmonary shunt provides a convenient opportunity to correct anomalous pulmonary venous return that was not repaired at the time of neonatal palliation. When a bidirectional Glenn anastomosis is performed in patients with drainage of the right pulmonary veins just above the superior cavoatrial junction, the superior caval vein is transected more craniad than usual, ensuring sufficient room above the entrance of the pulmonary veins to avoid possible obstruction. This technique is not applicable in patients undergoing any sort of Fontan connection that incorporates the right superior cavoatrial junction, is preferable to intraatrial baffle procedures because it is simple, does not require nonnative tissue, and carries a lower risk of obstruction or sinus node complications. With other forms of extracardiac anomalous pulmonary venous drainage, various techniques can be used to achieve pulmonary venoatrial connection, including anastomosis of a vertical vein to either the cardiac stump of the transected superior vena cava or either atrial appendage. It is important to remember that when patients with mildly reduced pulmonary blood flow undergo a bidirectional Glenn procedure as a primary palliation, this will further reduce pulmonary blood flow, and potential mild pulmonary venous obstruction may remain masked until Fontan completion.
For the Fontan procedure, it is our policy to perform extracardiac conduit total cavopulmonary anastomosis whenever possible, so almost all cases of primary palliation and bidirectional Glenn operation are performed with the eventual aim of constructing an extracardiac conduit Fontan circulation. In addition to its many other potential benefits, the extracardiac Fontan procedure is well-suited for definitive palliation of complex single-ventricle hearts with anomalous pulmonary venous drainage. Because the right atrium is not incorporated into the Fontan circuit with the extracardiac conduit approach, an effective common atrium receives all pulmonary venous blood. If necessary, atrial septectomy can (and should) be performed at primary palliation or during the bidirectional Glenn procedure. For example, patients with pulmonary venous drainage to the middle or systemic side of a common atrium, which constitutes a large portion of the patterns encountered in patients with heterotaxy [13–16], especially polysplenia (left isomerism), no pulmonary venous intervention is required at any stage of palliation if an eventual extracardiac Fontan is planned.
For other forms of anomalous pulmonary venous return in which division and atrial anastomosis is required, the effective common atrium allows for greater flexibility in anastomosis placement when the eventual aim is to perform an extracardiac conduit Fontan operation. Pulmonary veins draining anomalously via ascending or descending veins can be reanastomosed to the effective common atrium at any location that is convenient, including the cardiac stump of a ligated superior vena cava (right or left) at the time of bidirectional Glenn procedure or either atrial appendage. Several cases in our experience illustrate these concepts and are described in detail in a separate report [4].
In conclusion, anomalous pulmonary venous return can significantly complicate the management of the single-ventricle patient. Some form of pulmonary venous anomaly occurs in more than 60% of patients with asplenia [14–16] and approximately half of patients with polysplenia [13, 14]. Among patients with hypoplastic left heart syndrome, anomalous pulmonary venous return is present in 6% of patients, including those in whom a levoatriocardinal vein provides egress of pulmonary venous blood to the systemic veins [5, 17]. Thus, this remains a substantial problem, with the major impact on survival coming in the neonatal period. As we have outlined above, palliation with the aim of performing an extracardiac conduit total cavopulmonary anastomosis allows greater latitude and more streamlined management in this group of patients. Another important pulmonary venous complication that can occur in single-ventricle patients who have undergone an atriopulmonary Fontan operation is obstruction of the right pulmonary veins by an enlarged right atrium, which compresses the veins as they pass posterior to it en route to the left atrium. This complication can be managed in properly selected patients by revising the Fontan physiology to an extracardiac conduit total cavopulmonary anastomosis [18].
References
This article has been cited by other articles:
|
|
 |
|
  M. Koudieh, E D. McKenzie, and C. D Fraser Jr Outcome of Glenn Anastomosis for Heterotaxy Syndrome with Single Ventricle Asian Cardiovasc Thorac Ann, June 1, 2006; 14(3): 235 - 238. [Abstract] [Full Text] [PDF]
|
|
|
|
 |
|
 A. Azakie, S. L. Merklinger, W. G. Williams, G. S. Van Arsdell, J. G. Coles, and I. Adatia Improving outcomes of the Fontan operation in children with atrial isomerism and heterotaxy syndromes Ann. Thorac. Surg., November 1, 2001; 72(5): 1636 - 1640. [Abstract] [Full Text] [PDF]
|
|
|
|
|
|
L. D. Thompson, D. B. McElhinney, V. M. Reddy, K. L. Jue, and F. L. Hanley Infradiaphragmatic totally anomalous pulmonary venous return with two separate descending veins in association with right atrial isomerism Ann. Thorac. Surg., October 1, 2000; 70(4): 1400 - 1402. [Abstract] [Full Text] [PDF]
|
|
| ||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| ANN THORAC SURG | ASIAN CARDIOVASC THORAC ANN | EUR J CARDIOTHORAC SURG |
| J THORAC CARDIOVASC SURG | ICVTS | ALL CTSNet JOURNALS |
