Physiological rationale for a bidirectional cavopulmonary shunt. A versatile complement to the Fontan principle

The original Fontan procedure included a classic superior vena cava-to-right pulmonary artery (Glenn) shunt. Subsequent experience demonstrated that this anastomosis was not essential and was an unnecessary commitment of the larger right pulmonary circulation to the smaller blood volume of the superior vena caval return. With application of the Fontan principle to more complex cardiac malformations, there has been a reconsideration of possible benefits of a cavopulmonary shunt in selected patients. A modified shunt from the divided end of the superior vena cava to the side of the undivided right pulmonary artery utilized in 21 patients is described. This shunt is designed to allow bidirectional pulmonary arterial distribution of both superior vena caval inflow and right atrial outflow after completion of the Fontan procedure. Twelve patients had the bidirectional shunt performed prior to a Fontan operation; five of these had a subsequent atriopulmonary connection and seven await operation. Eight patients had construction of this shunt at the time of their Fontan procedure. One patient had a bidirectional shunt constructed following atriopulmonary anastomosis to help relieve right atrial outflow obstruction. Two patients with univentricular heart undergoing simultaneous Fontan procedure and a bidirectional shunt died while in the hospital. The remaining 19 patients have been followed up for 2 months to 9 years with one late sudden death at 9 years. There have been no bidirectional cavopulmonary shunt failures, stenoses, kinks, or recognized pulmonary arteriovenous malformations. Postoperatively, eight patients had assessment of pulmonary distribution of shunt blood flow by angiography. Seven of these patients were also evaluated by radionuclide angiography. Superior vena caval blood flow via the bidirectional cavopulmonary shunt tended to be greater to the right lung, but bilateral pulmonary flow was documented in all but one patient. After Fontan operation, six of seven patients tested also demonstrated bilateral distribution of atriopulmonary flow. We concluded from our experience that this modified shunt provides excellent relief of cyanosis, allows bidirectional pulmonary distribution of both superior vena caval return and also the right atrial blood flow after atriopulmonary connection, and may be done before, with, or after a Fontan procedure and is compatible with all currently recommended modifications. Perioperative hemodynamic adjustments to the Fontan procedure may be improved by reducing atrial volume, and this may also be of potential benefit in the long-term adaptation to Fontan physiology by minimizing atrial distention.     

Surgical treatments of nonconfluent pulmonary arteries with congenital cardiac defects]

Pulmonary artery angioplasty or reconstruction was performed in seven patients with nonconfluent pulmonary arteries and congenital cardiac defects. Age of these patients were ranged from 6 months to 41 years old. Five of them had pulmonary truncal atresia and complex cardiac anomalies. Two of these five patients demonstrated nonconfluent pulmonary arteries due to deformities at ductal insertion of pulmonary arteries. Three patients had had previous systemic to pulmonary artery shunt operations which caused pulmonary artery distortions. Other two patients had intrapulmonary arterial obstructions due to pulmonary artery thrombosis. Patch pulmonary artery plasty was carried out in three patients, dilatation of severe stenotic pulmonary artery was done in one patient simultaneously with pulmonary valvotomy. Central shunt operation was added in one patient with the pulmonary artery which was unable to be reconstructed. Last two patients underwent intrapulmonary artery reconstruction with the rolled pericardial graft. Hospital death occurred in one patient with unproperly increased pulmonary blood flow by central shunt. Average follow-up period of these six survivors after operation was 1.4 +/- 0.8 years. As definite repairs, two patients had Fontan operation, two patients had right ventricle to pulmonary artery reconstruction. And remaining two patients are still to be followed until sufficient growth of pulmonary artery suitable for Fontan operation.     

Reconstruction of nonconfluent pulmonary artery using the retroaortic innominate vein for a single ventricle

The innominate vein usually courses anterior to the aortic arch, where it joins the right brachiocephalic vein to form the superior caval vein. A retroaortic innominate vein is an uncommon finding in patients with congenital heart disease. We report a patient with a single ventricle, single atrium, pulmonary atresia, nonconfluent pulmonary artery, persistent left superior caval vein, absent inferior caval vein (azygos connection), right aortic arch, and retroaortic innominate vein. His innominate vein took an anomalous course. The right brachiocephalic vein crossed from right to left underneath the aortic arch and formed a left superior caval vein with the left brachiocephalic vein and the azygos vein. We reconstructed the nonconfluent pulmonary artery using the retroaortic innominate vein and then performed a total cavopulmonary shunt when he was 32 months of age. Thereafter, a total cavopulmonary connection was carried out at age 42 months.     

Staged Fontan operation for children with heterotaxy syndrome,bilateral ductus arteriosus,and nonconfluent pulmonary artery

We report two cases of successful Fontan operation in children with heterotaxy syndrome associated with univentricular physiology and absent and nonconfluent central pulmonary arteries with both distal pulmonary arteries directly connected to the ipsilateral ductus arteriosus. After unilateral systemic-pulmonary shunt, the central pulmonary artery was reconstructed with a polytetrafluoroethylene prosthetic graft concomitantly with bidirectional cavopulmonary shunt. Finally, extracardiac total cavopulmonary connection was performed as an off-pump procedure. Children with bilateral ductus arteriosus and a nonconfluent pulmonary artery with univentricular physiology present a particular challenge in regard to completing Fontan operations. Careful attention should be directed at ensuring balanced growth of the bilateral distal pulmonary arteries. When planning reconstruction of the central pulmonary artery with a prosthesis, late reconstruction may be beneficial, as it enables utilization of a larger-caliber graft, obviating the need for replacement during a subsequent Fontan operation.     

A case of isolated anomalous return of bilateral superior pulmonary veins

A 14-year-old girl was admitted for evaluation of heart murmur. Intravenous digital subtraction angiography (DSA) showed the right superior pulmonary vein drained into the superior vena cava and the left superior pulmonary vein drained into the innominate vein. At the operation, an anomalous bilateral superior pulmonary venous return with an intact atrial septum was confirmed. An atrial septal defect was created and the right superior pulmonary vein was baffled into the left atrium with a pericardial patch. The left superior pulmonary vein was divided and anastomosed to the left inferior pulmonary vein with a expanded polytetra-fluoro-ethylene graft. Post-operative DSA showed satisfactory long-term result of the operation.     

One-stage unifocalization followed by staged Fontan operation

We report a successful case of staged Fontan operation for single ventricle, pulmonary atresia, major aortopulmonary collaterals and absent central pulmonary artery. The one-stage unifocalization, concomitant with central pulmonary artery creation by autologous pericardium and modified Blalock-Taussig shunt at 1 month of age as the first palliation, and the Glenn operation and pulmonary arterial augmentation with superior vena caval patch at 9 months of age as the second palliation were performed. Extracardiac conduit Fontan operation was completed at 22 months of age. The pulmonary artery continued developing with increasing pulmonary arterial index and stable pulmonary arterial pressure throughout the clinical course. The one-stage unifocalization in early infancy and the repeated surgical intervention to the pulmonary artery without prosthetic material provided excellent pulmonary arterial growth and Fontan completion.     

Hemi-Fontan operation in surgery for single ventricle: a preliminary report

Mortality after Fontan operation is related to risk factors like ventricular hypertrophy, pulmonary artery deformity, and young age (infancy). Preliminary procedures may improve Fontan results. The hemi-Fontan operation includes atriopulmonary anastomosis and correction of all anatomical risk factors, but an atriopulmonary patch directs superior vena caval flow into both pulmonary arteries and inferior vena caval flow into the ventricle, thus maintaining cardiac output (modified Glenn physiology). We performed 17 hemi-Fontan procedures in 16 patients, 14 primarily (median age, 9 months) and 3 for takedown of a Fontan operation. The 14 primary operations were for hypoplastic left heart syndrome (5), pulmonary atresia with intact ventricular septum (4), and other (5). All patients had multiple risk factors. Extubation was at 18 hours (median), chest tube removal was at 3 days, and hospital discharge was at 8 days postoperatively. Important complications included subglottic stenosis, transient diaphragmatic paralysis, pulmonary artery stenosis and thrombosis requiring reoperation, and transient ventricular fibrillation. One patient required hemi-Fontan takedown, and this patient later (3 months postoperatively) became the only death. Fontan take-downs have had a high mortality rate. In 3 patients who tolerated Fontan operation poorly, converting Fontan to hemi-Fontan abruptly reversed the downhill course. For these patients, the operation was life-saving. Hemi-Fontan operation is safe and well-tolerated, even in infants, provides the advantages of modified Glenn physiology before Fontan operation, and may be especially useful for Fontan takedown after failed Fontan.     

Pulmonary artery configuration after palliative operations for hypoplastic left heart syndrome

Pulmonary artery architecture and symmetry after palliative operations for hypoplastic left heart syndrome may affect subsequent suitability for a modified Fontan operation. Two-dimensional echocardiography was used to measure pulmonary artery diameter and assess symmetry after two types of systemic-pulmonary artery shunts: modified right Blalock-Taussig shunt (14 patients) and central shunt (from underside of aortic arch gusset to pulmonary artery confluence) (14 patients). Age, weight, preoperative diameter of right and left pulmonary arteries (proximal, middle, and distal segments), and mean interval between preoperative and postoperative echocardiographic studies (20.2 +/- 4.4 days in the Blalock shunt group; 19.1 +/- 6.8 days in the central shunt group) were similar. Early postoperatively, patients with a Blalock shunt showed a significant decrease in the diameter of all pulmonary artery segments except the distal right pulmonary artery. The diameters tapered from distal right to distal left pulmonary artery in this group. Patients with the central shunt had a significant decrease in the diameter of all pulmonary artery segments. There were no significant differences when cross comparisons were made of the various pulmonary arterial segments in patients after a central shunt. Similar findings persisted in 19 patients from both groups who had a late postoperative echocardiogram (mean interval between studies = 271 days in the group of 10 patients with Blalock shunt and 167 days in the group of nine patients with a central shunt). In conclusion, the central shunt preserves pulmonary artery symmetry, which may be important in candidates for the Fontan operation in infancy.     

Alternative Fontan connection for apicocaval juxtaposition

We present an alternative technique to the modified Fontan procedure used in a 3-year-old boy who had complex heart defects with bilateral superior vena cava and apicocaval juxtaposition. The left superior vena caval pathway was used behind the ventricle to connect the inferior vena cava to the pulmonary artery. We proved the technical feasibility of this with good midterm results at the 5-year follow-up angiography.     

Tree-shaped Pulmonary Veins in Infracardiac Total Anomalous Pulmonary Venous Drainage

Three consecutive patients undergoing corrective operation for the infracardiac type of total anomalous pulmonary venous drainage (TAPVD) were found to have tree-shaped pulmonary veins. Preoperative angiocardiography revealed that in 2 patients the superior and inferior pulmonary veins drained separately, bilaterally, into the vertical vein. In the third patient the right pulmonary veins united to connect with the vertical vein, while the left superior and inferior pulmonary veins drained separately into the vertical vein. At operation inferior pulmonary veins connecting separately with the vertical vein were found to be located posterior to the pericardium.In the previous literature dealing with successful repair of infracardiac TAPVD, there is no mention of the tree-shaped pulmonary veins described in this report. As this particular type of pulmonary vein does not seem to be uncommon, its possible presence should be kept in mind during operation, as it may dictate the selection of surgical procedures.     

Staged Approach for Congenitally Corrected Transposition of the Great Arteries Associated with Dextrocardia and Nonconfluent Pulmonary Artery

Abstract   We completed double switch operation (Senning plus Rastelli procedure; SLL) after staged palliative operations for SLL, dextrocardia, congenitally corrected transposition of the great arteries ventricular septal defect, atrial septal defect, and nonconfluent pulmonary artery. The patient had undergone three preparatory operations including central pulmonary artery reconstruction with autologous pericardium and morphologic right ventricle-pulmonary artery shunt and then double switch operation was performed. During the double switch operation, the previous conduit which was established as right ventricle-pulmonary artery shunt in the third palliation was replaced by a larger conduit. This conduit was used as Rastelli external conduit to avoid coronary artery injury. When systemic venous chamber was reconstructed, suture line pouch technique was used, in which dog ears were made at the sites of superior and inferior vena cava orifices, respectively, to prevent systemic venous return obstruction. Pulmonary venous chamber was reconstructed without any augmentation, which reduced the possibility of postoperative arrhythmia. Systemic and pulmonary venous pathway obstructions were not observed after the operation. Postoperative arrhythmia was not detected.     

Totally anomalous pulmonary venous connection directly to the superior caval vein.

OBJECTIVE: Totally anomalous pulmonary venous connection directly to the superior caval vein is unusual. It is frequently associated with major congenital heart defects such as the syndrome of right isomerism. While improved results have been reported recently for the isolated form, complex cases are still associated with a higher mortality. METHODS: We undertook surgical correction in nine patients with direct pulmonary venous connection to the superior caval vein investigated in our institution from 1991 to 1999. In four of these patients, the venous anomaly was an isolated finding, while five patients with isomeric right atrial appendages had associated cardiac malformations rendering them unsuitable for biventricular repair. In one patient with an isolated form, the venous drainage was obstructed. Two patients with isomerism had previously undergone construction of an aortopulmonary shunt. Other associated surgical procedures in the patients with right isomerism were establishment of bidirectional cavo-pulmonary anastomoses in four cases and banding of the pulmonary trunk in one. RESULTS: There were neither early nor late deaths. Reoperation was needed in one patient because of pulmonary venous stenosis. In the five patients with right isomerism, two later underwent successful creation of the Fontan circulation. CONCLUSION: It is unusual to find direct drainage of all the pulmonary veins to the superior caval vein. When seen, the venous pathway is only rarely obstructed. For this reason, when associated with right isomerism, an aortopulmonary shunt should be constructed as initial palliation, with later repair of the anomalous pulmonary venous drainage at the time of construction of a bidirectional cavo-pulmonary anastomosis. When using this policy, the surgical results can be as good for the complicated variant as for the isolated form.     

Staged operation for right isomerism with total anomalous pulmonary venous return: report of a case

A male infant with right isomerism, single ventricle, severe pulmonary stenosis (PS), and total anomalous pulmonary venous return (TAPVR) underwent successful staged Fontan operation. Pulmonary vein drained into right superior vena cava without a stenotic lesion. Common pulmonary venous chamber was also connected with the atrium by a thin bridging vein. Blalock-Taussig shunt was performed at 2-month-old. Because of progressive pulmonary congestion, an anastomosis between common pulmonary venous chamber and the atrium followed 4 days after the first shunt. Bidirectional cavopulmonary shunt was performed 7 months after the second operation. Because of progressive atrioventricular valve regurgitation, repeated bandings of the shunt were required to regulate the pulmonary flow. Total cavopulmonary connection was completed 9 months after the BCPS. Staged operation is a useful strategy to acquire an appropriate pulmonary blood flow for the isomeric heart with TAPVR and severe PS.     

The fenestrated Kawashima operation for single ventricle with interrupted inferior vena cava

An 8-month-old boy with double outlet right ventricle with hypoplastic left ventricle, heterotaxy, left atrial isomerism, bilateral superior vena cavae without bridging vein, and interruption of the inferior vena cava with azygous continuation to the left superior cava underwent a bilateral bidirectional cavopulmonary anastomosis. A calibrated 3-mm connection between the right pulmonary artery and the common atrium was constructed with the proximal right superior vena cava to allow right to left shunting, analogous to a fenestration in a Fontan operation. We hypothesize that in small young patients undergoing the Kawashima operation a fenestration may improve postoperative hemodynamics.     

New surgical approach "intrapulmonary septation technic" for Fontan candidates with unilateral pulmonary arterial hypoplasia and/or pulmonary venous obstruction

Unilateral pulmonary arterial hypoplasia and/or pulmonary venous obstruction are serious hazards for Fontan candidates. For these patients, we have started new surgical approach "intrapulmonary septation technic". This consists of 3 components; (A) partial right heart bypass to well-grown side, (B) mandatory pulmonary blood flow to low-capacity side, (aorto-pulmonary shunt or others) and (C) a patch between partial right heart bypass and mandatory pulmonary blood flow. Thirteen patients underwent the approach. The source of partial right heart bypass was brought from superior vena cava (11 patients), inferior vena cava (1 patient) and fenestrated Fontan (1 patient). The mandatory pulmonary blood flow was supplied by aorto-pulmonary shunt (11 patients), pulmonary arterial banding (1 patient) and native pulmonary valve stenosis (1 patient). We added pulmonary artery enlargement (9 patients), release of pulmonary venous obstruction (8 patients) and/or atrio-ventricular valve plasty (5 patients), simultaneously. No hospital death. Early post-operative course was uneventful in all cases except 1, as pulmonary blood flow to low-capacity side had increased gradually after this intervention. Eight patients had reached Fontan operation. In this approach, nearly whole pulmonary artery can grow without any affect of volume overload through well-grown side from collateral arteries of low-capacity side. All procedures of "intrapulmonary septation technic" and reconstruction of pulmonary artery in Fontan operation can be easily performed in larger pulmonary artery of well-grown side, eliminating need for extensive dissection.     

Pulmonary blood flow measurements following vena cava-to-pulmonary artery anastomosis

The distribution of pulmonary blood flow was investigated in 2 patients 13 and 9 years following vena cava-to-pulmonary artery anastomosis. Angiographic and radioactive flow studies revealed a wide-open vena cava-to-pulmonary artery anastomosis which became larger proportional to the patient's growth. The passage of contrast material through the lung was swift and unimpeded; however, perfusion of the apical portion of the right lung appeared less than satisfactory. There was a complete separation between the systems of the superior and inferior caval veins, and contrast material and radioactive albumin injected into the system of the superior caval vein entered the right lung exclusively.On the basis of these observations, it is our opinion that if vena cava-to-pulmonary artery anastomosis is done with a proper operative indication and a satisfactory surgical technique, one should not expect late development of intercaval collaterals and decrease in the efficiency of the vena cava-to-pulmonary artery shunt.     

Redirection of hepatic venous drainage after total cavopulmonary shunt in left isomerism

BACKGROUND: Conversion from total cavopulmonary shunt (TCPS) to the Fontan circulation can improve cyanosis in patients with potential risks of development of pulmonary arteriovenous fistula (PAVF). METHODS: Inclusion of the hepatic veins in the pulmonary circulation was employed using an intra-atrial tube graft in 5 patients with left isomerism previously undergoing TCPS. Prior to the conversion, abnormal communication was identified between the azygos vein and either the hepatic or the portal vein in all. PAVF was seen in 3. RESULTS: All patients survived the procedure. Postoperative catheterization showed 13 +/- 2 mm Hg of superior caval venous pressure, and 2.3 +/- 0.4 L/min/m2 of cardiac index. Pulmonary arteriovenous fistula progressed markedly in the right lung even after the conversion in 2 patients, in whom the hepatic veins had been exclusively diverted to the left lung. Arterial oxygen saturation became below 65%, with exercise capacity reduced, in these 2 patients. The other patients remain asymptomatic. CONCLUSIONS: Total cavopulmonary shunt can be efficiently converted to the Fontan circulation by appropriately redirecting hepatic venous drainage to perfuse both lungs in a balanced fashion.     

Modified extracardiac Fontan in a patient with separate hepatic venous drainage

We describe an alternative technique to the extracardiac Fontan procedure in a patient with a univentricular heart, in which the inferior caval vein and the hepatic vein drained separately into the common atrium and the intraatrial orifice of the hepatic vein was adjacent to the opening of the left lower pulmonary vein.     

Scimitar syndrome with left pulmonary hypertension and right pulmonary artery stenosis in childhood--report of a case of successful surgical repair

An one-year old child with Scimitar syndrome (anomalous drainage of the right pulmonary vein to inferior vena cava with right lung hypoplasia) associated with left side pulmonary hypertension and right pulmonary artery stenosis underwent surgical repair. The anomalous pulmonary vein was anastomosed to right atrium with 10 mm PTFE graft interposition and drained to left atrium through equine pericardial intra-atrial baffle. The stenotic portion of right pulmonary artery was enlarged with porcine pericardial patch. To our knowledge, this is the first successful surgical case of Scimitar syndrome with pulmonary hypertension in childhood reported in literature. A repair of anomalous pulmonary venous drainage to inferior vena cava in childhood is difficult, and a meticulous selection of surgical procedure is necessary.     

Fontan procedure for hypoplastic left heart syndrome.

Since 1985, 354 neonates have undergone palliative reconstruction for hypoplastic left heart syndrome with 109 early deaths and 12 late deaths. Of the survivors, before 1989, 77 patients underwent a subsequent modified Fontan operation, consisting of baffling the atrial septal defect to the tricuspid valve (initial 25 patients) or intraatrial baffling of the inferior vena cava to the pulmonary arteries and superior vena cava (52 patients). There were 17 early deaths and three late deaths. Major serous effusions developed in 42 patients (54%) after Fontan operation. Since 1989, a staged approach to Fontan's operation was undertaken in an effort to reduce the volume load of the right ventricle as early as possible, to minimize the impact of rapid changes in ventricular geometry and diastolic function that can accompany a primary Fontan operation, and to reduce effusive complications. Thus, at a mean age of 6 months, 121 patients have undergone closure of aortopulmonary shunt, augmentation of central pulmonary arteries, and association of the superior vena cava with the branch pulmonary arteries (hemi-Fontan procedure). Of these, 61 patients have already undergone completion of the Fontan procedure with six early deaths and three late deaths. Major serous effusions developed in 28 patients (46%) with the staged Fontan. For perspective, the contemporary experience since January 1991 consists of 58 neonates who have undergone initial palliation with 11 deaths (19%), 17 patients who have undergone the hemi-Fontan procedure with one death (6%), and 21 patients who have undergone completion of the Fontan operation with one death (5%).(ABSTRACT TRUNCATED AT 250 WORDS)