Partial Fontan: advantages of an adjustable interatrial communication

Systemic venous hypertension after the Fontan procedure is a major cause of mortality and morbidity, accounting for 11 of 16 deaths in our series of 228 Fontan procedures. A partial Fontan with a residual atrial septal defect (ASD) would allow controlled right-to-left shunting to reduce venous pressure and improve cardiac output while maintaining a reduced but acceptable arterial oxygen saturation. This allows complete or graded closure of the ASD after the discontinuation of cardiopulmonary bypass in the operating room or at any time in the postoperative period by exposing the snare under local anesthesia. From 1987 to 1990, 36 patients undergoing the modified Fontan procedure had placement of an adjustable interatrial communication. Indications for placement of an adjustable ASD included increased pulmonary artery pressures, increased pulmonary vascular resistance, reactive airway disease, previously increased or unknown pulmonary vascular resistance, small pulmonary arteries, and borderline ventricular function. Fourteen patients had the adjustable ASD closed at the time of operation, 8 patients underwent narrowing, and 12 underwent closure of the ASD in the postoperative period. Eight patients were discharged with the ASD partially open, and 2 patients underwent delayed closure. The partial Fontan with an adjustable ASD may increase the safety of the Fontan procedure for high-risk groups such as those with increased pulmonary vascular resistance, pulmonary hypertension, and impaired left ventricular function and for infants, who tolerate venous hypertension poorly. The ability to adjust the ASD in stages depending on the hemodynamic response increases flexibility and safety.     

Midterm results of surgical treatment of systemic ventricular outflow obstruction in Fontan patients

BACKGROUND: Achieving unobstructed blood flow from the systemic ventricle to the aorta is important during the Fontan procedure for complex cyanotic congenital heart disease when there is systemic ventricular outflow obstruction (SVOO). Because SVOO can progress after the Fontan procedure if there is morphologic obstruction, we have adopted a policy of relieving obstructions to systemic blood flow. METHODS: Twenty-five patients were treated by the Fontan procedure with SVOO. Twenty-one patients had undergone prior pulmonary artery banding and 10 patients had undergone prior arch repair. Systemic ventricular outflow obstruction progressed in 5 patients after the Fontan procedure. Main diagnosis was single ventricle in 12, tricuspid atresia in 5, transposition of the great arteries in 4, double-outlet right ventricle in 3, and common atrioventricular canal in 1. Mean age at operation was 6.5 years (range 1 to 15 years) and the average preoperative pressure gradient across the ascending aorta and systemic ventricle was 29 mm Hg (range 0 to 100 mm Hg). The Damus-Kaye-Stansel procedure was performed in 18 patients (double-barrel anastomosis in 13, end to side anastomosis in 5), and subaortic resection or ventricular septal defect or bulboventricular foramen enlargement was performed in 7. Double-barrel anastomosis has been our first choice since 1994, if the pulmonary valve is intact. Follow-up has ranged from 4 months to 14 years (average 5.0 years). Twenty-three of the 25 patients have undergone recatheterization (average 21.4 months later). RESULTS: No early deaths were found; one late death was reported of a patient with single right ventricle (4.0%). The postoperative average pressure gradient was 1.1 mm Hg (0 to 10 mm Hg), and the average right atrial pressure was 14 mm Hg (9 to 20 mm Hg). In all patients who underwent ventricular septal defect or bulboventricular foramen enlargement, regular sinus rhythm was maintained postoperatively. Regarding the Damus-Kaye-Stansel procedure, there was minimal progression of semilunar valve insufficiency except in 1 patient who underwent end-to-side anastomosis with moderate pulmonary regurgitation postoperatively. CONCLUSIONS: The midterm results of the Fontan procedure with SVOO have been satisfactory. Because SVOO might progress after the Fontan procedure if there is morphologic obstruction, an appropriate strategy to relieve obstruction to systemic blood flow should therefore be performed concomitantly with the Fontan procedure.     

Creation of a One-Way Interatrial Communication in the Treatment of Critical Pulmonary Stenosis with Intact Ventricular Septum: A Case Report

A bstract Background : In biventricular repair of pulmonary outflow tract obstruction with intact ventricular septum, the right ventricle is loaded with total pulmonary blood flow acutely as the right-to-left shunt is abolished by closure of the atrial septal defect (ASD). Methods : We designed a one-way interatrial communication by creation of an atrial septal flap to reduce the excessive volume load of the right ventricle. Results : This procedure was successfully performed in a 3-year-old girl undergoing definitive biventricular repair for critical pulmonary stenosis associated with tricuspid stenosis and a small right ventricle. Conclusions : We believe that creation of a one-way interatrial communication might be a good alternative to adjustable ASD and/or bidirectional Glenn shunt in biventricular repair of critical pulmonary stenosis or pulmonary atresia with intact ventricular septum.     

Partial biventricular repair for double-outlet right ventricle with left ventricular hypoplasia

The presence of left ventricular hypoplasia in double-outlet right ventricle may increase the risk of biventricular repair and Fontan procedures. The hypoplastic left ventricle of an 11-year-old girl with complex double-outlet right ventricle was successfully incorporated in a modified biventricular repair by Dacron patch closure of the ventricular septal defect, diversion of venous return of the inferior vena cava to the mitral valve with an intraatrial baffle, insertion of a left ventricular apex to pulmonary artery valved aortic homograft, and diversion of residual systemic venous return directly to the lungs with a bidirectional superior vena cava to pulmonary artery shunt. Postoperatively, the systemic venous atrial pressure was 6 mm Hg and the pulmonary artery pressure was 14 mm Hg. This method is proposed as a partial biventricular repair hemodynamically superior to the Fontan procedure, although aortic homograft revision may be required in the future.     

Cor triatriatum associated with large atrial septal defect and partial anomalous pulmonary venous return. Case report

A rare variant of cor triatriatum is presented with a large true atrial septal defect and partial anomalous pulmonary venous return into the right atrium. The correct diagnosis was made at the operation and abnormal left atrial septum was excised completely and a new interatrial septum was created with pericardial patch in such a position that the abnormally drained right upper pulmonary vein was left in the left atrium. It was thought to use the abnormal left atrial septum to close the atrial septal defect by excising only the right lateral border of this abnormal septum and resuturing it to the right atrial wall to close the true atrial septal defect. This thought could not be realized because of the small size of this abnormal septum and large size of the atrial septal defect. This technique can be realized in small or medium sized atrial septal defects associated with cor triatriatum.     

Cyanosis in atrial septal defect without pulmonary hypertension: a case of platypnea-orthodeoxya syndrome

Cyanosis in atrial septal defect typically occurs when pulmonary hypertension develops. Platypnea-orthodeoxya is an uncommon syndrome, still under debate, characterized by breathlessness and arterial oxygen desaturation exacerbated in the upright position. An interatrial communication is a common finding in this syndrome, but the absence of a right to left pressure gradient complicates the physiopathological picture. To explain the right to left shunt, it is generally advocated a concomitant condition that alternates the sterical relationship between inferior vena cava orifice and the atrial septal defect. A case of a 58-year-old male with platypnea-orthodeoxya syndrome related to a fenestrated redundant interatrial septum without any additional pathologic condition is reported. Possibly, this isolated anatomical abnormality could lead to a right to left shunt in the absence of other coexisting predisposing factors. It is reasonable to hypothesize the septum secundum bulging like a 'spinnaker' into the right atrium, so that it deviates the inferior vena cava venous blood towards the left atrium. Echocardiographic evaluation is mandatory to achieve a correct diagnosis and to decide the therapeutic strategy.     

The Fontan procedure in the absence of the interatrial septum. Failure of its principle?

The Fontan principle, defined as a procedure in which the right ventricle is bypassed in order to convey desaturated venous blood from the right atrium to the lungs, is presently applied for a wide variety of congenital heart malformations including those in which there is no suitable ventricular pumping chamber. Recently, the procedure has also been advocated for complex malformations that require atrial septation or intra-atrial rerouting. The present report evaluates our experience in four patients with such complex malformations. Three had a complete form of atrioventricular septal defect with double-outlet right ventricle and one patient had left atrioventricular valve atresia. The common atrium was morphologically right in two patients and morphologically left in one. In each of these instances anomalous pulmonary venous connections were present, together with abnormal systemic venous connections. The results were unsatisfactory. Three of the four patients died. The only survivor had no pulmonary or systemic venous abnormalities. Severe impairment of pulmonary blood flow was one of the most important postoperative complications. The findings suggest that the complexities of rerouting the blood within the atria play an important role. The excess proportion of prosthetic material to atrial myocardium may result in excessive loss of contractile atrial myocardium and, probably equally significant, in a complex intra-atrial geometry of pathways that may cause a critical pressure gradient. The results clearly show that with an expanding horizon of the application of the Fontan principle, new pitfalls may arise which presently appear to be the prevailing factors limiting its success.     

Turbulent left-to-right shunt flow through the interatrial septum suggesting high left atrial pressure in patients with heart failure with preserved ejection fraction

Lutembacher’s syndrome is a combination of interatrial septal (IAS) defect or patent foramen ovale (PFO), associated with mitral stenosis. High left atrial (LA) pressure in mitral stenosis exaggerates left-to-right shunt in patients with interatrial communication. We present a case of heart failure with preserved ejection fraction. Echocardiography revealed normal left ventricular systolic function without mitral stenosis and turbulent left-to-right shunt through the IAS. The peak velocity of the shunt flow was 2.3 m/s and the estimated pressure gradient was 22 mmHg, indicating high LA pressure. The presence of turbulent left-to-right shunt through the IAS is helpful for detecting high LA pressure.     

The recognition, identification of morphologic substrate, and treatment of subaortic stenosis after a Fontan operation. An analysis of twelve patients.

Twelve children were identified with subaortic stenosis after Fontan's operation. All had absent resting and isoproterenol-provoked pressure gradient before the Fontan procedure. Six had a univentricular heart of left ventricular morphology, three had a single ventricle of right ventricular morphology, one had tricuspid atresia with transposition of the great arteries, one had pulmonary atresia, intact ventricular septum, and hypoplastic right ventricle, and one had corrected transposition with hypoplastic systemic ventricle. The median interval between the Fontan operation and the recognition of subaortic stenosis was 2.5 years. Ten patients underwent surgical treatment after a prior Fontan operation: Five had myectomy and enlargement of ventricular septal defect with two operative deaths; two had placement of a valved conduit from the ventricular apex to the descending aorta, and both died postoperatively; two with single ventricle had subaortic myectomy, and one had enlargement of ventricular septal defect and pulmonary aortic connection. Complete heart block developed in only one patient. Postoperative testing with Doppler echocardiography with color flow imaging demonstrated good relief of subaortic stenosis. All six children who survived the operation are well 4 months to 4 years later. Subaortic stenosis is a progressive lesion that may develop after a Fontan operation. Its surgical treatment continues to carry a significant mortality. Myectomy and enlargement of ventricular septal defect achieve direct relief of the obstruction with minimal risk of heart block.     

Central cyanosis due to prominence of the eustachian and thebesian valves.

A 9-year-old female child with serious central cyanosis was found to have right to left shunt across a large secundum atrial septal defect despite normal right-sided pressures. Preoperative cross-sectional echocardiography suggested the presence of large sinus venosus eustachian and thebesian valves as the mechanism responsible for diversion of the inferior caval and coronary sinus venous return to the left atrium across the interatrial secundum defect. Surgical excision of the unduly prominent sinus venosus valve and patch closure of the atrial septal defect resulted in complete disappearance of the cyanosis and physiological and clinical cure.     

Intermediate procedures after first-stage Norwood operation facilitate subsequent repair

Actuarial analysis of survival after first-stage palliative reconstructive operation for hypoplastic left heart syndrome has revealed a high out-of-hospital attrition rate over the first 18 months to 2 years postoperatively. Some of this mortality is related to development of anatomical problems such as restrictive atrial septal defect, neoaortic arch obstruction, and pulmonary artery distortion. The bidirectional Glenn shunt has proved to be an ideal adjunctive procedure for high-risk patients at the time of operation to correct such intermediate-term problems. The fenestrated Fontan procedure, which involves fenestration of the interatrial baffle placed as part of our current standard Fontan procedure, is applied for patients considered to be at moderate risk for a Fontan procedure. The decision regarding closure of the fenestration is made by hemodynamic study including temporary balloon occlusion of the fenestration. The fenestration is closed with the double-clamshell device, which is placed percutaneously in the catheterization laboratory and which is currently used for secundum atrial septal defect closure. Appropriate selection of patients for the bidirectional Glenn shunt or fenestrated Fontan procedure with or without fenestration closure has resulted in a dramatic decrease in mortality and morbidity for patients with all forms of single ventricle and for patients with hypoplastic left heart syndrome.     

Repairing interatrial septal defects from the operating room to the cardiac catheterization laboratory: 2D or not 2D?

Uncorrected congenital interatrial septal defect can be found in nearly a third of all adults and are associated with significant morbidity, including pulmonary hypertension, right-heart failure, atrial arrhythmias, and paradoxical embolic stroke. With advancing technology, percutaneous closure of atrial septal defects has become a viable alternative to open surgical repair. In this review, the authors provide 3 examples in which 3-dimensional interventional transesophageal echocardiogram effectively provided more precise visualization of the dynamic surface and geometry of the atrial septum and related structures than 2-dimensional TEE, permitting accurate sizing and repair of the defects.     

A reconsideration of risk factors for the Fontan operation.

We reviewed our experience in 38 patients who underwent a Fontan operation. In the first five patients ages 7.5 to 23 years (mean, 15 years), a conduit was placed from the right atrium to the small right ventricle or the pulmonary artery (PA). The remaining 33 patients, ages 7 months to 14 years (mean, 4.8 years), had a modified Fontan operation with direct systemic venous or right atrial to PA anastomosis. The diagnoses were tricuspid atresia (n = 14), single ventricle (n = 10), hypoplastic right or left ventricle (n = 9), double-outlet right ventricle with inlet ventricular septal defect and pulmonary atresia or stenosis (n = 3), criss-cross ventricles and transposition of the great arteries (n = 1), and atrioventricular canal and anomalous pulmonary venous connection (n = 1). Thirty-two patients had previous surgery. Other procedures included PA banding (n = 7), systemic to PA shunts (n = 25), Norwood operation (n = 3), and a Damus-Kaye-Stansel anastomosis (n = 1), repair of total anomolous pulmonary venous connection (n = 1), a Blalock-Hanlon atrial septectomy (n = 1), and enlargement of a restrictive ventricular septal defect (n = 1). There were four operative deaths (10.5%), three from low cardiac output and one from subaortic obstruction. There were no deaths in patients younger than 3 years of age (n = 13). Subaortic obstruction developed in six of the seven patients who had pulmonary artery banding and resulted in three deaths. In our experience, diagnosis, previous surgery, type of previous operation, PA pressure, and younger age are not risk factors for early or late death. Subaortic obstruction is a major risk factor for late death. Accordingly we now perform a Damus-Kaye-Stansel anastomosis combined with a systemic to PA shunt in those children with excessive pulmonary blood flow who anatomically are likely to develop subaortic obstruction. A modified Fontan operation can be performed any time after 1 year of age and in some patients after 6 months of age, providing the anatomy and physiology of the patient are acceptable.     

Surgical management of trabecular ventricular septal defects: the sandwich technique

BACKGROUND: Surgical closure of trabecular ventricular septal defects is difficult and often unsuccessful. OBJECTIVE: We performed closure of trabecular ventricular septal defects by sandwiching the septum between 2 polyester felt patches placed in the left ventricle and right ventricle without ventriculotomy. METHODS: Eleven patients (7 boys and 4 girls) underwent a sandwiching closure at a mean age of 4.7 years (range, 0.4-9.7 years) and a mean weight of 16.7 kg (range, 4.6-52 kg). Associated cardiac malformations were present in 9 of the 11 patients. Seven patients had undergone previous operations. The trabecular ventricular septal defects are exposed through the tricuspid valve and also from the left ventricular side through a coexisting large perimembranous ventricular septal defect or through the mitral valve through an interatrial septostomy. Two forceps, one each from the right and left ventricular side, lead a 3F Nelaton catheter through the trabecular defect. An oversized circular polyester felt patch mounted on a 3-0 Nespolen suture attached to the Nelaton catheter is then passed into the left ventricle. The suture ends are then passed through a slightly smaller polyester felt patch on the right ventricular side of the septum. The Nespolen suture is then tied, thereby sandwiching the septum between the 2 patches. RESULTS: Time required for the procedure was less than 20 minutes in each case. There were no hospital deaths, and the postoperative course was uneventful in all patients. There was no residual shunt in 3 patients, and a minimal residual shunt was observed in 5 patients. Mild residual shunt was observed in 3 patients. Cardiac catheterization was performed 1 month postoperatively in 8 patients in whom residual shunt was noted on echocardiography. Five of 8 patients had a minimal residual shunt (pulmonary blood flow/systemic blood flow ratio = 1.0). Three patients had a residual shunt (pulmonary blood flow/systemic blood flow ratio = 2.0, 1.6, and 1.2). The patient with a pulmonary blood flow/systemic blood flow ratio of 2.0 had a "Swiss cheese" ventricular septal defect, and a residual shunt remained around the patch. However, the residual shunt decreased to a pulmonary blood flow/systemic blood flow ratio of 1.6 at examination 16 months postoperatively. Echocardiography showed that the residual shunt had also decreased in another 2 patients. CONCLUSIONS: We conclude that the sandwich technique is safe and easy. Even in cases with a residual shunt present, the shunt is expected to decrease as time passes. Further experience and longer follow-up of these patients are necessary to conclude whether this technique is applicable to neonates and young infants.     

Surgical closure of sinus venosus atrial septal defect using a single patch--transcaval repair technique

Abstract Objective: We would like to share our experience of surgical repair of sinus venosus atrial septal defect (ASD) using a simple “transcaval repair technique.” Method: Between January 2007 and October 2010, 48 consecutive patients of sinus venosus ASD underwent surgical repair using transcaval repair technique at our institute. Their ages ranged from 5 to 15 years and male to female ratio was 1.6:1. The principles of the technique were longitudinal incision over the lateral aspect of superior vena cava (SVC) at the entry point of anomalous right pulmonary veins, use of a single autologous untreated pericardial patch, and finally closure of the caval incision in such a way that the patch gets sandwiched between two caval lips. Results: All 48 patients came off cardiopulmonary bypass in sinus rhythm. The average pressure gradient across the patch was 3 mmHg. Immediate postoperative electrocardiograms and echocardiograms showed all patients were in sinus rhythm with no residual shunt and no pulmonary or systemic venous obstruction respectively, except in one patient who required SVC augmentation. The follow‐up was done at three months (100%), one year, and two years. All patients were asymptomatic and their electrocardiograms and transthoracic echocardiograms revealed sinus rhythm, no residual shunt, and no obstruction to systemic or pulmonary venous drainage, respectively. There was no early or late mortality. Conclusion: We conclude that this technique is safe and simple for the repair of selected cases of sinus venosus atrial septal defect with partial anomalous pulmonary venous connection and it preserves the sinoatrial node function after surgery. (J Card Surg 2011;26:429‐434)     

Left ventricular outflow obstruction after Fontan procedure involving a patient with complete atrioventricular septal defects complicated by a small left ventricle

We report a 1-year-old girl who developed ventricular outflow tract obstruction early after a Fontan operation, necessitating surgical relief using the Damus-Kaye-Stansel procedure. The patient had a complete atrioventricular septal defect complicated by a muscular ventricular septal defect (VSD) and a small left ventricle, a morphology that has not previously been reported in cases of systemic outflow tract obstruction after the Fontan procedure. Postoperative systemic outflow obstruction must be considered as a possible sequela following Fontan surgery in patients with an atrioventricular septal defect and a small left ventricle.     

Modification of the radial procedure in a patient with partial atrioventricular septal defect

We successfully cured atrial fibrillation while preserving internodal conduction in a patient with a partial atrioventricular septal defect. Because the anterior and middle internodal tracts are interrupted by the defect, the lower right atrial incision of either the maze or the radial procedure may interrupt the remaining posterior tract, resulting in internodal conduction block. We deleted the posterior septal incision from the radial procedure and replaced it with a right-side left atriotomy. The patient resumed normal sinus rhythm with significant contraction of the right and left atria. The preserved internodal pathway through the posterior interatrial septum was confirmed by electrophysiologic study.     

Syndrome of single ventricle without pulmonary stenosis but with left atrioventricular valve atresia and interatrial obstruction. Palliative management with simultaneous atrial septostomy and pulmonary artery banding

Case histories of four infants with single ventricle and left atrioventricular (AV) valve atresia, with interatrial obstruction but without pulmonic stenosis, are presented. Relief of interatrial obstruction by surgical or balloon atrial septostomy resulted in a marked fall in the left atrial pressure and the pulmonary artery mean pressure and resistance as well as a marked increase in the left-to-right interatrial shunt, pulmonary blood flow, and systemic arterial oxygen saturation. Because of this predictable fall in pulmonary vascular resistance, concomitant pulmonary artery banding was performed in each case with good results. There are only a few previously reported cases of single ventricle with left AV valve atresia. Interatrial obstruction is quite common in this lesion. The concept that relief of interatrial obstruction produces a rapid and predictable fall in the pulmonary vascular resistance and that concomitant pulmonary artery banding is necessary in these infants with complex congenital heart disease is emphasized.     

Residual Right-to-Left Shunt Following Repair of Atrial Septal Defect

Information about 5 patients with residual right-to-left shunts following repair of an atrial septal defect is presented. In each patient the defect was located low in the atrial septum adjacent to the inferior vena cava. During operation, either the eustachian valve of the inferior vena cava had been mistaken for the lower margin of the defect or the lower portion of the defect was not closed; blood flow was then diverted from the inferior vena cava into the left atrium. To prevent this occurrence, the inferior margin of the atrial septal defect should be closed first.     

Aortopulmonary collateral flow in the Fontan patient: does it matter?

BACKGROUND: The effects of aortopulmonary collaterals (APCs) on the outcome of a Fontan procedure are unclear. We undertook this study to define the incidence and extent of APC flow, identify risk factors for APC flow, and determine if APC flow has a measurable effect on the outcome of a Fontan procedure. METHODS: The APC flow was directly measured in 32 patients undergoing Fontan procedures from July 1997 to September 2000. The APC flow was measured in the operating room during total cardiopulmonary bypass, and was expressed as a percentage of total bypass pump flow. RESULTS: The APC flow ranged from 9% to 49% of total pump flow (median, 18%). Higher preoperative systemic oxygen saturation, pulmonary artery oxygen saturation, pulmonary to systemic flow ratio, and angiographic APC grade correlated with higher APC flow. There were no operative deaths; there was one Fontan takedown (APC flow = 14%). The APC flow had no significant effects on postoperative Fontan pressure, common atrial pressure, transpulmonary gradient, duration of effusions, or resource utilization after the Fontan procedures. CONCLUSIONS: In patients undergoing a Fontan procedure, APC flow is omnipresent, although its extent varies widely. Increased APC flow has no significant effect on the outcome of a Fontan procedure. This conclusion applies to patients who are well prepared for a Fontan procedure, but may not extend to patients at higher risk.