Characterization and treatment of systemic venous to pulmonary venous collaterals seen after the Fontan operation

OBJECTIVES: To determine the anatomical characteristics of systemic venous collaterals formed after the Fontan operation, and the efficacy of a transcatheter strategy for management. METHODS: We reviewed retrospectively the data from cardiac catherization of 50 persistently cyanotic patients after the Fontan operation. RESULTS: A total of 54 transcatheter interventions were performed, at a mean age of 6.3 +/- 3.5 years, a mean interval of 2.7 +/- 2.9 years from completion of the Fontan circulation. Of 38 patients who had fenestration of the baffle at the time of surgery, 25 had patency of the fenestration, and 24 had the fenestration occluded with a device at the time of interventional treatment for associated venous collaterals. We identified a total of 68 systemic venous collateral channels, of which 36 (53%) were supracardiac, 12 (18%) cardiac, and 20 (29%) infracardiac in origin. The most common site of origin was the brachiocephalic vein (44%), followed by the left phrenic vein (25%). A longer time from surgery, at 3.3 +/- 3.4 years, was associated with the identification of collaterals having a diameter larger than 4 mm (p < 0.01). The mean pulmonary arterial pressure was higher in those with larger compared to those with smaller collaterals (13.3 +/- 2.8 versus 11.1 +/- 2.0 mmHg, p < 0.01). Coils were used for occlusion of 61 vessels, and a Rashkind occluder for the remaining 7. After exclusion of the patients undergoing simultaneous closure of their fenestration, systemic saturation of oxygen increased from 89 +/- 6% to 95 +/- 3% (p < 0.01). CONCLUSION: Venous collateral channels are common in patients suffering progressive cyanosis in the setting of the Fontan circulation. The collaterals increase in size with time, and are associated with higher pulmonary arterial pressures. Transcatheter treatment is feasible, and results in resolution of cyanosis. Only continuing follow-up will show whether further collateralization occurs in time.     

Diagnostic assessment before Fontan operation in patients with bidirectional cavopulmonary anastomosis: are noninvasive methods sufficient?

OBJECTIVES: This study was designed to determine if a subset of patients who have undergone bidirectional cavopulmonary anastomosis could be identified in which catheterization was of little benefit before completion of the Fontan procedure. BACKGROUND: Diagnostic evaluation before Fontan procedure has typically included cardiac catheterization. However, the overall management strategy for patients with functional single ventricle has evolved to include staging bidirectional cavopulmonary anastomosis in most, and it has become uncommon to exclude patients from Fontan based on catheterization data. METHODS: Patients who underwent bidirectional cavopulmonary anastomosis and had complete echocardiograms and catheterizations within three months of each other between January 1992 and October 1997 were evaluated with a series of clinical and echocardiographic characteristics to identify a subset in whom catheterization was predicted to be of little added value ("no-cath" group). The predictive value and sensitivity of these criteria in excluding patients who required additional intervention, were excluded from Fontan, or died within 30 days of Fontan was determined. RESULTS: A total of 99 patients who underwent bidirectional cavopulmonary anastomosis at 6.7 months (range 2.9 months to 14 years) were studied; 46 met criteria for the "no-cath" group. Noninvasive criteria stratified all patients who died (n = 5) or did not proceed to Fontan (n = 1) and 9 of 11 who required additional interventions to the "cath" group. Thus, the negative predictive value of these criteria was 93%. CONCLUSIONS: Our data suggest that catheterization before Fontan could be avoided in a large percentage of patients without adversely affecting outcome; prospective evaluation of this strategy is warranted.     

Interventional occlusion of interatrial communication after modified Fontan operation

After modified Fontan operations various communications between the systemic and pulmonary venous returns may cause persistent or increasing postoperative cyanosis. Interventional closure of these right-to-left shunts may be necessary to eliminate hypoxemia and to reduce the risk of paradoxical embolic complications. PATIENTS AND METHODS: Eighteen patients with a mean age of 5.6 +/- 4.1 (2.5-17.5) years underwent interventional closure of a right-to-left shunt 17.4 +/- 15.8 (3-60) months after a modified Fontan operation. After test balloon occlusion fenestrations were closed in 13 patients using an Amplatzer Septal occluder (n = 7), a Rashkind PDA occluder (n = 3), a CardioSeal umbrella (n = 1) and detachable coils (n = 2). Residual leaks at the suture lines between the interatrial patch and the right atrial wall were closed using detachable coils and a Rashkind PDA occluder in 2 and 1 patients, respectively. In 3 patients intracardiac venous collateral channels were closed by means of detachable coils. RESULTS: The mean aortic oxygen saturation increased from 85 +/- 4.5 (70-89)% to 91.4 +/- 2.8 (83-95)% (p < 0.001) breathing room air and the mean tunnel pressure rose from 10.7 +/- 1.8 (6-14) mmHg to 12.1 +/- 2.4 (6-16) mmHg (p < 0.001). Calculated Qs decreased from 5.15 +/- 2.1 (2.1-11.3) l/min/m2 to 3.6 +/- 1.0 (1.8-5.6) l/min/m2 (p < 0.001). Mixed venous saturation (66.4 +/- 7.4% vs 65 +/- 7%) and mean systemic arterial pressure (73 +/- 8 mmHg vs 73 +/- 9 mmHg) remained unchanged. In one patient an additional leak of the tunnel could not be closed because of an increase to more than 18 mmHg of the mean pressure in the lateral tunnel during balloon test occlusion. In 2 patients residual leaks after umbrella and coil occlusion of a fenestration and an additional venous collateral channel were closed by means of coils after 16 and 21 months, respectively. At a follow-up of 42 +/- 23 (7-99) months, mean oxygen saturation measured by pulse oxymetry was 93 +/- 2 (90-97)%. In 2 patients color-coded Doppler echocardiography revealed a minimal residual right-to-left shunt. In 2 patients contrast echocardiography demonstrated the additional presence of intrapulmonary fistulas. All patients remained free from device migration, thromboembolic events and hemolysis. CONCLUSION: After modified Fontan operations various right-to-left shunts between the systemic and pulmonary venous returns can be successfully closed using umbrella devices or coils to eliminate cyanosis and to reduce the risk of paradoxical embolism.     

Systemic venous collateral channel causing desaturation after bidirectional cavopulmonary anastomosis: percutaneous closure

An infant with cyanotic cardiac disease that was palliated with a bidirectional cavopulmonary shunt developed progressive and worsening cyanosis 5 years after the surgical procedure. A large venous collateral was found to be decompressing the bidirectional Glenn shunt from the superior caval vein to the inferior caval vein and was percutaneously closed with a vascular plug. The unusually large venous collateral, and the excellent outcome associated with percutaneous procedure are discussed.     

Somatic growth in children with single ventricle physiology impact of physiologic state.

OBJECTIVES: We sought to define somatic growth patterns for patients with single ventricle (SV) physiology and associated factors. BACKGROUND: Infants with SV physiology might have somatic growth retardation associated with volume overload and hypoxemia, which might improve after surgical palliation. METHODS: We reviewed 126 patients (35% male) who underwent the Fontan procedure from 1994 to 2004. Demographic data, hemodynamic variables, and surgical procedures were recorded. Serial weights and heights were converted to z-scores. Linear regression analysis adjusted for repeated measures was used to model growth trends. RESULTS: Median z-score for weight was -0.7 at birth, -1.6 before bidirectional cavopulmonary shunt (BCPS), -0.7 before Fontan procedure, and -0.7 after Fontan procedure. A significant decline in z-scores for weight was seen before BCPS, which was reversed after the hemi-Fontan and stabilized after Fontan procedure. The z-scores for weight before the BCPS were lower in patients with lower birth weight (p < 0.01), nutritional difficulties (p = 0.01), and higher right atrial pressures (p = 0.02). After the BCPS, impaired growth was seen in patients who had systemic venous collaterals (p < 0.01). Patients who had collaterals embolized had the same growth trends as patients with no collaterals (p = 0.29). CONCLUSIONS: Infants with SV physiology show impaired somatic growth before BCPS. Although catch-up growth occurs after BCPS, effective interventions such as more intensive nutritional strategies before BCPS might be targeted at this high-risk population. The presence of systemic venous collaterals might impede growth secondary to hemodynamic impairment. Embolization of collaterals might allow for maximum growth potential.     

Surgical considerations of univentricular heart with total anomalous pulmonary venous connection

Out of the 600 patients undergoing univentricular repair during the last 11 years, 20 children had associated total anomalous pulmonary venous connection. The objective was to outline the clues to establish the diagnosis of this rare disease combination and the various surgical options available to manage the same. Bidirectional Glenn, bilateral bidirectional Glenn, total cavopulmonary connection and atriopulmonary connection were performed in combination with rechannelling of various types of total anomalous pulmonary venous connection in 20 children aged 6 months to 36 months (mean +/- SD 17.65 +/- 9.02 months). Diagnosis could be established pre-operatively in only 13 (65%) patients. Out of 6 early deaths (30%), 4 were directly attributable to missed diagnosis. No late deaths occurred over a follow-up period ranging from 1 month to 132 months. None of the surviving children required reoperation and all are in NYHA functional class I. Doppler echocardiography of the surviving children revealed unrestricted atrio/cavopulmonary anastomosis and pulmonary vein to atrium connection in all survivors. Our own experience, coupled with a review of the literature, indicates that a missed diagnosis increases the hospital mortality. Cross sectional 2D echocardiography is a superior method of detection of associated total anomalous pulmonary venous connection compared to angiocardiography. Exclusion of the diagnosis of anomalous pulmonary venous connection is imperative in all univentricular hearts pre-operatively and on operation table. Failure to recognise this disease combination results in formation of a closed systemic circuit after bidirectional Glenn or a modified Fontan of connection and is lethal as happened in our early experience. It is suggested that one-stage Fontan operation should be performed only if other criteria for Fontan procedure are satisfied.     

Transcatheter recanalization of ligated main pulmonary artery.

A 12.5-year-old boy with tricuspid atresia and quadriplegic cerebral palsy presented with increasing cyanosis after previous palliation with a cavopulmonary shunt and ligation of the main pulmonary artery (MPA). Because of severe physical disabilities he was not considered suitable for Fontan completion. He underwent successful transcatheter stent recanalization of the ligated MPA. This re-established anterograde flow to the pulmonary arteries resulting in marked improvement in saturations.     

Bidirectional cavopulmonary anastomosis in congenital heart disease. Functional and clinical outcome.

The bidirectional cavopulmonary anastomosis is a surgical procedure suitable for patients with cyanotic congenital heart disease and univentricular physiology. This operation is able to increase the effective pulmonary blood flow without any additional load on the cardiac work and without any further distortion on the pulmonary artery branches. The cavopulmonary anastomosis can represent the first stage for patients destined for Fontan repair or a definitive palliative operation in high risk Fontan candidates. In order to test the hypothesis of a definitive palliation by cavopulmonary anastomosis in this kind of patients, we evaluated the hemodynamic data before and after this surgical approach and compared these data with their clinical and functional outcome. We evaluated 74 patients submitted to bidirectional cavopulmonary anastomosis by either hemodynamic or functional evaluation. End-diastolic and end-systolic ventricular volumes were significantly reduced by bidirectional cavopulmonary anastomosis (p less than 0.0005). Despite these data and a normal ambulatory ECG, spirometry and echocardiographic analysis, the stress test showed discouraging results. In fact, mean work time and peak heart rate were significantly different from normal values showing an impaired functional capacity of these children. In conclusion we think that bidirectional cavopulmonary anastomosis can not be considered an adequate definitive palliation but it represents a very good stage to preserve the pulmonary arteries and to prepare the systemic ventricle towards the Fontan repair.     

Caval contribution to flow in the branch pulmonary arteries of Fontan patients with a novel application of magnetic resonance presaturation pulse

BACKGROUND: A complete understanding of fluid mechanics in Fontan physiology includes knowledge of the caval contributions to right (RPA) and left (LPA) pulmonary arterial blood flow, total systemic venous return, and relative blood flow to each lung. METHODS AND RESULTS: Ten Fontan patients underwent cine MRI. Three cine scans of the pulmonary arteries were performed: (1) no presaturation pulse, (2) a presaturation pulse labeling inferior vena cava (IVC) blood (signal void), and (3) a presaturation pulse labeling superior vena cava (SVC) blood. The relative signal decrease is proportional to the amount of blood originating from the labeled vena cava. This method was validated in a phantom. Whereas 60+/-6% of SVC blood flowed into the RPA, 67+/-12% of IVC blood flowed toward the LPA. Of the blood in the LPA and RPA, 48+/-14% and 31+/-17%, respectively, came from the IVC. IVC blood contributed 40+/-16% to total systemic venous return. The distributions of blood to each lung were nearly equal (RPA/LPA blood=0.94+/-11). CONCLUSIONS: In Fontan patients with total cavopulmonary connection, SVC blood is directed toward the RPA and IVC blood is directed toward the LPA. Although the right lung volume is larger than the left, an equal amount of blood flow went to both lungs. LPA blood is composed of equal amounts of IVC and SVC blood because IVC contribution to total systemic venous return is smaller than that of the SVC. This technique and these findings can help to evaluate design changes of the systemic venous pathway to improve Fontan hemodynamics.     

Reopening of persistent left superior caval vein after bidirectional cavopulmonary connections

Persistent left superior vena cava (SVC) is a not uncommon finding in patients with congenital heart disease. This anatomical variant must be recognised before doing a Glenn anastomosis, bidirectional cavopulmonary connection or a Fontan-type procedure. Following these procedures, reopening of a left SVC leading to clinical cyanosis can occur. Five cases are described in whom persisting left SVCs were excluded before performing a bidirectional cavopulmonary connection or Fontan procedure but (re-)opened after surgery, leading to cyanosis either by reducing effective pulmonary blood flow (bidirectional cavopulmonary connection) or by an obligatory right to left shunt (Fontan). These observations suggest that, embryologically, the lumen of the left SVC obliterates rather than disappears. Balloon occlusion angiography of the innominate vein before cavopulmonary connections or Fontan procedures might improve detection of these collateral vessels.

Keywords: persistent left superior vena cava; cavopulmonary connection; Fontan procedure; congenital heart disease     

Outcome of single ventricle and total anomalous pulmonary venous connection

Management of patients with single-ventricle physiology is significantly affected by anomalies of pulmonary venous return at all stages, whether primary palliation, bidirectional Glenn shunt, or completion of Fontan circulation. We treated 25 patients with pulmonary venous anomalies and single ventricle by staged palliation, from June 1996 to May 2005. Visceral heterotaxy with atrial isomerism was present in 19 of them. Primary palliation with a systemic-to-pulmonary artery shunt was undertaken in 15 patients. There were 5 early deaths, of which 4 were due to obstruction of pulmonary venous return. A bidirectional Glenn shunt was constructed in 17 patients including 10 who had it as a primary palliative procedure. There were 7 early deaths after the bidirectional Glenn procedure; only one was due to pulmonary venous obstruction. Five patients attained completion of the Fontan procedure. There was one early death after the Fontan operation. Anomalous pulmonary venous return can significantly complicate the management of patients with single ventricle, with an impact on survival in early infancy. Palliation with the aim of instituting extracardiac conduit Fontan circulation allows greater latitude and more streamlined management.     

Pathogenetic mechanisms of venous congestion after the Fontan procedure

BACKGROUND: The hemodynamic status after a Fontan type procedure for definitive palliation of functionally univentricular hearts is dominated by a high central venous pressure, which seems to be one of several factors responsible for venous congestion appearing as a frequent complication in the early and late postoperative course. The purpose of our study was to find other hemodynamic parameters correlating with the presence of venous congestion and effusions in these patients. METHODS: We compared the hemodynamic data of 18 patients who had an uneventful long-term course after a Fontan type procedure with the respective data of 10 patients who developed symptoms of venous congestion in the immediate postoperative period. Based on a theoretical model, we developed an algorithm to calculate mean hydrostatic capillary pressure from mean arterial pressure, systemic vascular resistance index and central venous pressure. RESULTS: Pulmonary vascular resistance index (2.1 +/- 1.0 mmHg L-1 min m2), mean left atrial pressure (9.7+/-4.0 mmHg) and cardiac index (3.6+/-0.6 l/min/m2) are mainly normal in patients with venous congestion in the immediate postoperative period, but mean hydrostatic capillary pressure is significantly higher compared to patients without venous congestion (24.3+/-3.1 vs 18.3+/-4.0 mmHg). Lower mean hydrostatic capillary pressures in these patients are due to a highly significant increase of systemic vascular resistance index (18.6+/-4.2 versus 33.6+/-6.6 mmHg L-1 min m2) and a concomitant decrease of cardiac index to 2.4+/-0.3 l/min/m2. CONCLUSIONS: The increase of mean hydrostatic capillary pressure, caused by high central venous pressures but also by relatively low systemic vascular resistance indexes, seems to be the hemodynamic key parameter responsible for venous congestion and effusions in patients after a Fontan type procedure in the immediate postoperative period.     

Effect of baffle fenestration on outcome of the modified Fontan operation.

BACKGROUND. The "fenestrated Fontan" (surgical baffle fenestration followed by transcatheter test occlusion and permanent closure after postoperative recovery) was adopted in an effort to reduce perioperative mortality and morbidity. This study assesses the effect of baffle fenestration on outcome. METHODS AND RESULTS. Patients having a modified Fontan operation with a cavocaval baffle and cavopulmonary anastomosis were retrospectively selected for study. Those with baffle fenestration (n = 91) were compared with those without baffle fenestration (n = 56) with respect to preoperative risk factors, age, anatomy, surgical date, and presence or absence of a previous bidirectional cavopulmonary anastomosis. Outcome variables were failure (death or take-down) and duration of postoperative pleural effusions and hospitalization. Survival and clinical status after hospital discharge were ascertained. The two groups did not appear to differ with respect to age or anatomic diagnosis. Patients having baffle fenestration were at significantly greater preoperative risk by univariate and multivariate analysis (p < 0.01). Operative failure was low in both groups (11% without and 7% with baffle fenestration, p = NS). Durations of pleural effusions and hospitalization were significantly shorter with baffle fenestration (p < 0.01). Neither date of surgery nor a previous bidirectional cavopulmonary anastomosis appeared to contribute to improved outcome. Patients with baffle fenestration had lower postoperative systemic venous pressure (p < 0.01). There were no late deaths. Functional status in both groups is good (82% in New York Heart Association class I). CONCLUSIONS. Baffle fenestration is associated with low mortality, significantly less pleural effusion, and significantly shorter hospitalization among high-risk patients having a modified Fontan operation.     

Impact of early ventricular unloading on exercise performance in preadolescents with single ventricle Fontan physiology.

OBJECTIVES: We sought to determine if early ventricular volume unloading improves aerobic capacity in patients with single ventricle Fontan physiology. BACKGROUND: Surgical strategies for patients with single ventricle include intermediate staging or early Fontan completion to reduce the adverse affects of prolonged ventricular volume load. The impact of this strategy on exercise performance has not been evaluated. METHODS: Retrospectively, we reviewed the exercise stress test results of all preadolescents with single ventricle Fontan physiology. "Volume unloading" was considered to have occurred at the time of bidirectional cavopulmonary anastomosis or at the time of Fontan surgery in those patients who did not undergo intermediate staging. Potential predictors of aerobic capacity were analyzed using multivariate regression. RESULTS: The patients (n = 46) achieved a mean percentage predicted of maximal oxygen consumption (VO2max) of 76.1% +/- 21.1%. The mean age at the time of volume unloading was 2.7 +/- 2.4 years, and the mean age at testing was 8.7 +/- 2 years. Intermediate staging was performed in 16 of 46 patients (35%). In multivariate analysis, younger age at volume unloading was associated with increased aerobic capacity (p = 0.003). Other variables were not predictive. The subgroup of patients who underwent volume unloading before two years of age achieved a mean percentage predicted VO2max of 88.6% +/- 24.1%. CONCLUSIONS: Preadolescents with single ventricle who undergo volume unloading surgery at an early age demonstrate superior aerobic capacity compared with those whose surgery is delayed until a later age.     

Cardiac catheterization and test occlusion of the interatrial communication after the fenestrated Fontan operation

Objectives. Our objective was to determine whether catheterization data obtained after a fenestrated Fontan operation influenced patient management or predicted functional status.

Background. Cardiac catheterization after a fenestrated Fontan operation is undertaken to identify residual lesions and to observe the patient's response to test occlusion of the baffle fenestration.

Methods. Sixty patients undergoing both a fenestrated Fontan operation before July 1991 and a postoperative catheterization before March 1992 were included in the study. Catheterization data were collected according to a test occlusion protocol; these data were reviewed, and the patient's clinical status at follow-up was ascertained.

Results. Test occlusion resulted in a significant increase in systemic venous pressure, arterial oxygen saturation and arteriovenous difference in oxygen content (p < 0.0001). After test occlusion, systemic venous pressure was 40% higher and systemic venous saturation 23% lower among patients with an unfavorable versus a favorable response to test occlusion, although differences between the two groups were subtle or inapparent in the baseline state. Branch pulmonary artery stenosis (identified and balloon dilated in 6 patients) and grade 2 or 3 aortopulmonary collateral vessels (identified and coil embolized in 20) were associated with elevation in systemic venous pressure (p < 0.01). After an average of 2 years of follow-up, there were no deaths, and 50 (83%) of 60 patients were in New York Heart Association functional class I. The only postoperative characteristic significantly associated with being in functional class I at follow-up was a systemic venous pressure <17 mm Hg.

Conclusions. Cardiac catheterization with test occlusion of the interatrial communication provides useful information after a fenestrated Fontan operation. Conditions associated with elevated systemic venous pressure should be sought and treated, and the response of systemic venous pressure to test occlusion should be considered when deciding whether to close an interatrial communication.     

Feasibility and clinical impact of transcatheter closure of interatrial communications after a fenestrated Fontan procedure: medium-term outcomes.

OBJECTIVE: This study was to review an institutional experience with transcatheter closure of Fontan fenestrations and its impact on clinical care. BACKGROUND: An interatrial fenestration improves postoperative outcomes in high-risk children undergoing a Fontan repair. While technical feasibility has been well defined, the clinical impact of subsequent closure is not well defined. METHODS: Transcatheter closure of a surgically created or additional interatrial communication was attempted in 152 children at a median interval of 13.8 months after surgery. The clinical records were reviewed for demographic and anatomical characteristics, previous surgeries; catheterization data, and status at latest follow-up. RESULTS: Mean oxygen saturation and right atrial pressure increased acutely from 87% +/- 5% to 96% +/- 3% (P < 0.001) and 12 +/- 2 mm Hg to 13 +/- 3 mm Hg (P < 0.001), respectively. Higher systemic venous atrial pressures after occlusion correlated with higher pulmonary artery pressures (P = 0.05) before the Fontan procedure and with higher right (P < 0.001) and left atrial (P = 0.001) and ventricular end-diastolic pressures (P < 0.001) immediately before occlusion. Complications included device malposition in 2 children, 1 child each had an air embolism and post-procedural bleeding, and each self-limiting and 1 child had acute ST elevation in inferior ECG leads because of occlusion of the acute marginal branch which was treated with angioplasty and placement of a stent. At follow-up (median 4.5 years), the mean oxygen saturation was 95% +/- 3%. Residual interatrial leaks were noted echocardiographically in 9%. Two children developed protein-losing enteropathy after fenestration closure. No deaths or strokes were observed in follow-up. CONCLUSIONS: Transcatheter occlusion of Fontan fenestrations is safe with acute and persistent improvements in oxygen saturations.     

Outcome and assessment after the modified Fontan procedure for hypoplastic left heart syndrome.

BACKGROUND. We reviewed the outcome of 76 consecutive patients (age range, 5 months to 6 years; median age, 19 months) who underwent a modified Fontan procedure after initial palliative surgery for hypoplastic left heart syndrome (HLHS) between January 1984 and December 1989. METHODS AND RESULTS. Modifications of the Fontan procedure included transatrial baffle of pulmonary venous return to the tricuspid valve (n = 10) or inferior vena cava baffle within the right atrium to the superior vena caval-pulmonary artery anastomosis, with pulmonary artery augmentation (n = 66). Actuarial survival rates were 74% (1 month), 58% (12 months), 56% (2 years), and 52% (4 years). Of the 43 survivors, 25 patients have returned for postoperative cardiac catheterization at a medium of 13 months after the Fontan procedure. Mean +/- SD hemodynamic values were cardiac index, 2.8 +/- 0.6 l/min/m2; right arterial pressure, 11 +/- 2 mm Hg; pulmonary artery wedge pressure, 6 +/- 3 mm Hg; and arterial oxygen saturation, 94 +/- 3%. No patient had significant tricuspid or native pulmonary valve insufficiency. CONCLUSIONS. Survival after the Fontan procedure in patients with HLHS is comparable to survival after a Fontan procedure in patients with other complex congenital heart lesions. In the subgroup of patients with HLHS who survived both reconstructive surgery and a Fontan procedure and have been evaluated by cardiac catheterization after a Fontan procedure, the use of the right ventricle as the systemic ventricle yielded excellent intermediate results for Fontan physiology.     

Late systemic desaturation after total cavopulmonary shunt operations.

OBJECTIVES--To assess the medium-term results of total cavopulmonary shunt operations in children with left atrial isomerism, interrupted inferior vena cava, and complex congenital heart defects. BACKGROUND--Creation of a total cavopulmonary shunt provides very good interim palliation for children with interrupted inferior vena cava and complex congenital heart disease; however, longer term results after this operation have not been reported. METHODS--Detailed follow up of six children who underwent creation of a total cavopulmonary shunt at a tertiary referral centre. RESULTS--There were no early or late deaths. Oxygen saturations at discharge ranged from 89% to 92% (mean 90%). At last follow up (mean 4.7 years) saturations at rest ranged from 73% to 81% (mean 77%) (P < 0.05). All patients underwent exercise stress testing. At peak exercise oxygen saturations ranged from 62% to 87% (mean 71.5%) and during recovery from 68% to 85% (mean 78%). Cardiac catheterisation was performed in five patients with saturations of less than 80% at rest or peak exercise. No patient had pulmonary arteriovenous fistula. Systemic venous to hepatic venous collaterals were documented in four patients. These were localised below the diaphragm in three and above the diaphragm in one patient. The collateral vessel was successfully embolised in three of these patients, with a rise in resting oxygen saturations from 6 to 10% (mean 7%). CONCLUSIONS--The development of systemic venous to hepatic venous collaterals is a common complication in patients who undergo a total cavopulmonary shunt operation. This can lead to significant desaturation at rest and during exercise. Detailed angiographic studies of the infradiaphragmatic system veins is required for diagnosis. Transcatheter embolisation of such vessels gives good relief.     

Aggressive coil embolization for connected aortopulmonary collateral arteries with large shunts developed after diaphragmatic plication performed after cavopulmonary connection to facilitate fontan circulation

We present two patients of univentricular physiology, who underwent diaphragmatic plication following the complication of diaphragmatic paralysis resulting from a bidirectional Glenn procedure. Over several months, complex connections developed between aortopulmonary collateral arteries, resulting in large shunts around the plication sites and an increased central pulmonary artery (PA) pressure to 14–15 mmHg. Most blood flow from these connections was reversed in the lower PAs of the affected side, reaching the contralateral lungs through the central PAs. Selective angiography identified almost all of the feeding arteries and complex connections. Aggressive coil embolization at these sites decreased the PA pressure to approximately 10 mmHg, enabling the Fontan procedure. © 2013 Wiley Periodicals, Inc.     

Reopening of a persistent left superior vena cava in the early postoperative period following bidirectional cavopulmonary anastomosis--treatment by coil embolization]

Diagnosis of systemic venous drainage is mandatory for patients with congenital heart disease planned for cavopulmonary anastomosis or any Fontan-type palliation. Preexisting venous channels as the persistent left superior vena cava are common in cardiac anomalies and may lead to postoperative deterioration and cyanosis. We describe a 6 month old boy with a complex imbalanced atrioventricular septal defect who developed cyanosis in the very early postoperative period, following bidirectional cavopulmonary anastomosis. It was caused by ineffective lung perfusion due to a reopened persistent left superior vena cava with drainage to the coronary sinus.He underwent coil embolization of the persistent left superior vena cava with retrievable coils and cyanosis improved. Coil embolization is an effective alternative to secondary surgery, especially for hemodynamically compromised patients in the postoperative period.