Pulmonary Arteriovenous Malformations in Children After the Kawashima Operation

Outcomes of Patients Undergoing the Kawashima Procedure at an Early Age: A Single Center Experience

BACKGROUND

Previous reports have demonstrated the safety and efficacy of performing early Kawashima procedure (KP). Despite this, more recent studies have shown that the average age at the time of operation remains greater than one year of age. We report our experience with performing KP at an earlier age than previously reported.

METHODS

A retrospective review was completed of patients undergoing KP at a single center (January 2000 to June 2020). Clinical outcomes were examined.

RESULTS

Initial palliation was performed in 11 out of 12 patients. Age and weight at time of KP were 8.25 months (6.4-9.7) and 7.7 kg (6.5-8.6). Intensive care unit stay was 3.16 days (1-12), overall length of stay was 9.5 days (3-22). There was one unplanned reoperation, and no mortality in the cohort. Discharge oxygen saturation was 88% (80%-98%). Seven patients developed pulmonary arteriovenous malformations (PAVMs) with six proceeding to hepatic vein incorporation (HVI). Interval time to development of PAVMs was 42.3 months (16-121). Four of the 12 patients were left with antegrade pulmonary blood flow (PBF) and three (75%) remain without PAVMs. Median follow-up was 10 years (1.5-22) with 11 of 12 (91.67%) survival for the cohort.

CONCLUSIONS

The KP can be done at a younger age than previously reported with adequate early and late results. Most patients will go on to develop PAVMs and require HVI but leaving patients with some antegrade PBF is likely protective but will need further investigation to show definitive benefit.

Outcomes of the Kawashima: A Society of Thoracic Surgeons Congenital Heart Surgery Database Analysis

BACKGROUND

We aimed to evaluate the effect of age at operation on postoperative outcomes in children undergoing a Kawashima operation.

METHODS

The Society of Thoracic Surgeons Congenital Heart Surgery Database was queried for Kawashima procedures from January 1, 2014, to June 30, 2020. Patients were stratified by age at operation in months: 0 to <4, 4 to <8, 8 to <12, and >12. Subsequently, outcomes for those in whom the Kawashima was not the index operation and for those undergoing hepatic vein incorporation (Fontan completion or hepatic vein-to-azygos vein connection) were evaluated.

RESULTS

We identified 253 patients who underwent a Kawashima operation (median age, 8.6 months; median weight, 7.4 kg): 12 (4.7%), 0 to <4 months; 96 (37.9%), 4 to <8 months; 81 (32.0%), 8 to <12 months; and 64 (25.3%), >12 months. Operative mortality was 0.8% (n = 2), with major morbidity or mortality in 17.4% (n = 44), neither different across age groups. Patients <4 months had a longer postoperative length of stay (12.5 vs 9.3 days; P = .03). The Kawashima was not the index operation of the hospital admission in 15 (5.9%); these patients were younger (6.0 vs 8.4 months; P = .05) and had more preoperative risk factors (13/15 [92.9%] vs 126/238 [52.9%]; P < .01). We identified 173 patients undergoing subsequent hepatic vein incorporation (median age, 3.9 years; median weight, 15.0 kg) with operative mortality in 6 (3.5%) and major morbidity or mortality in 30 (17.3%).

CONCLUSIONS

The Kawashima is typically performed between 4 and 12 months with low mortality. Morbidity and mortality were not affected by age. Hepatic vein incorporations may be higher risk than in traditional Fontan procedures, and ways to mitigate this should be sought.

Fontan completion of a 10-year-old Kawashima patient with extensive arteriovenous malformations: consideration for a lobectomy

A significant contributing factor to the progression of late cyanosis in individuals undergoing Kawashima operation is pulmonary arteriovenous malformations. Following the Fontan procedure, arteriovenous malformations may regress. However, in cases with extensive malformations causing severe cyanosis, lobectomy can also be a possible treatment approach. Thereby, we present our two-step treatment strategy in a late Fontan completion complicated by arteriovenous malformations in a Kawashima patient.

Preservation of Antegrade Pulmonary Blood Flow in Kawashima Procedure With Prior Right Ventricular Outflow Tract Stent

Surgical management of single ventricle with interrupted inferior vena cava and azygos continuation typically requires a Kawashima procedure with subsequent completion of Fontan. However, this group is at risk of development of pulmonary arteriovenous malformations. Evidence suggests preservation of hepatic venous flow into the pulmonary circulation can potentially delay this development. We hereby describe a method of preserving antegrade pulmonary blood flow during the Kawashima procedure in the setting of prior right ventricular outflow tract stents.

Increases in oxygen saturation following discharge from Fontan palliation - an indicator of resolution of pulmonary arteriovenous malformations?

BACKGROUND

Pulmonary arteriovenous malformations in single ventricle congenital heart disease are poorly understood. Previous studies investigating pulmonary arteriovenous malformations predominantly focus on patients with heterotaxy syndrome and interrupted inferior caval vein. It is unknown if development and resolution of pulmonary arteriovenous malformations are similar for patients with and without heterotaxy syndrome.

METHODS

In this retrospective single-institution study, we identified patients with a history of single ventricle congenital heart disease and Fontan palliation. We then matched patients with heterotaxy syndrome (intact and interrupted inferior caval vein) and non-heterotaxy hypoplastic left heart syndrome. To compare development of pulmonary arteriovenous malformations, we identified the frequency of positive diagnoses pre-Fontan. To compare resolution of pulmonary arteriovenous malformations, we recorded oxygen saturation changes for 12 months following Fontan.

RESULTS

A total of 124 patients were included. Patients with heterotaxy and interrupted inferior caval vein were more likely to have a pre-Fontan contrast echocardiogram performed (p < 0.01) and more likely to be diagnosed with pulmonary arteriovenous malformations pre-Fontan (p < 0.01). There was no difference in oxygen saturation prior to Fontan, yet all patient groups had increased their oxygen saturations in the first year after Fontan discharge.

CONCLUSIONS

Pulmonary arteriovenous malformations are variably diagnosed prior to Fontan palliation; however, all study groups had increased oxygen saturations after Fontan discharge, potentially indicating resolution of pulmonary arteriovenous malformations in all groups. The prevalence of pulmonary arteriovenous malformations pre-Fontan is likely underestimated. A quantitative, systematic approach to diagnosis and follow-up of pulmonary arteriovenous malformations is needed to better understand susceptibility and pathophysiology.

Pulmonary vascular disease in Fontan circulation-is there a rationale for pulmonary vasodilator therapies?

The Fontan circulation is a palliative concept for patients with univentricular hearts. The central veins are connected directly to the pulmonary arteries (cavo-pulmonary connection) to separate the pulmonary and the systemic circulation. There is no sub-pulmonary ventricle that generates pressure to drive blood through the pulmonary arteries. Pulmonary blood flow is determined by central venous pressure (CVP) and pulmonary vascular resistance (PVR). The capability of the Fontan circulation to compensate for alterations in PVR is limited, as CVP can only be increased within narrow ranges without adverse clinical consequences. Consequently, systemic ventricular preload and cardiac output are dependent on a healthy lung with low PVR. Failure of the Fontan circulation is relatively common. In addition to ventricular dysfunction, maladaptive pulmonary vascular remodeling resulting in increased pulmonary resistance may play a key role. The pathophysiology of the maladaptive vascular processes remains largely unclear and diagnosis of an increased PVR is challenging in Fontan circulation as accurate measurement of pulmonary arterial blood flow is difficult. In the absence of a sub-pulmonary ventricle, pulmonary artery pressure will almost never reach the threshold conventionally used to define pulmonary arterial hypertension. There is a need for markers of pulmonary vascular disease complementary to invasive hemodynamic data in Fontan patients. In order to treat or prevent failure of the Fontan circulation, pathophysiological considerations support the use of pulmonary vasodilators to augment pulmonary blood flow and systemic ventricular preload and lower CVP. However, to date the available trial data have neither yielded enough evidence to support routine use of pulmonary vasodilators in every Fontan patient nor have they been helpful in defining subgroups of patients that might benefit from such therapies. This review discusses potential pathomechanisms of pulmonary vascular disease; it summarizes the current knowledge of the effects and efficacy of pulmonary vasodilator therapy in Fontan patients and tries to outline areas of potential future research on the diagnosis and treatment of pulmonary vascular disease and Fontan failure.

Pulmonary arteriovenous malformations in children after the Kawashima procedure: Risk factors and midterm outcome

Background:

Pulmonary arteriovenous malformations (PAVMs) are the major cause of progressive cyanosis in patients palliated with bidirectional cavopulmonary connection (BCPC). The aim of our study is to analyze the occurrence of PAVMs in patients after Kawashima procedure, to study the effect of total cavopulmonary connection (TCPC) on PAVMs, to evaluate the effect of axillary arteriovenous fistula (AAVF) creation on PAVMs, and to study the risk factors for PAVMs.

Methods:

In this retrospective cohort study, all patients with left isomerism and azygous continuation of an interrupted inferior vena cava who underwent Kawashima procedure from July 2001 to December 2017 were included.

Results:

Twenty.six patients after Kawashima procedure were included in our study. PAVMs were diagnosed in 12 patients (46%). Five of these 12 patients underwent TCPC with complete resolution of hypoxemia. Three patients underwent AAVF creation, 2 had complete resolution, while 1 had partial resolution of hypoxemia. Fourteen patients (54%) did not develop PAVMs. Nakata index below 267 mm²/m²and McGoon ratio below 1.9 predicted the development of PAVMs with high sensitivity and specificity.

Conclusions:

PAVMs represent a serious complication in patients who undergo Kawashima procedure. Small size of pulmonary arteries is an important risk factor for the development of PAVMs. Resolution of hypoxemia after TCPC completion supports the hepatic factor hypothesis. Early TCPC completion in these patients may help to avoid the development of PAVMs by restoring the hepatic factor. Resolution of hypoxemia after AAVF creation may support the lack of pulsatile flow hypothesis.

Modification of Glenn anastomosis for total cavopulmonary connection conversion after atriopulmonary Fontan

As several complications can develop after the atriopulmonary Fontan procedure, total cavopulmonary connection conversion is often considered. We report two cases in which total cavopulmonary connection conversion was performed with a modified Glenn procedure. We used an expanded polytetrafluoroethylene graft between the superior vena cava and extracardiac conduit. This procedure ensures that a balanced hepatic blood flow is perfused into both lungs to avoid pulmonary arteriovenous malformations.

The heterotaxy syndrome: associated congenital heart defects and management

Heterotaxy syndrome (HS) constitutes a spectrum of anomalies arising from embryological errors that result in abnormalities of lateralization involving thoraco-abdominal viscera and culminate in loss of normal asymmetric arrangement of these organs. Besides the unique challenges involved in planning and execution of surgical procedures aimed at correction or palliation of these anomalies, they have the potential to cause profound physiological and immunological consequences in the individual patient due to their cardiac and extra-cardiac manifestations. This article aims to review the literature on this rare and extraordinary subset of developmental anomalies with the intention of familiarizing the reader on the modes of presentation, manifestations, and the variations thereof while dealing with this anomaly. In our institutional experience with HS, 75 consecutive patients were seen between January 2011 and September 2018. Of these, 48 (64%) were confirmed to have isomerism of right atrial appendages (IRAA) and the rest had isomerism of left atrial appendages (ILAA). The cardiac and extra-cardiac manifestations of these patients were listed out. Fifty-four patients (34 with IRAA and 20 with ILAA) underwent 83 surgical procedures. While 49 patients were palliated on the univentricular pathway, 5 underwent biventricular repair. The in-hospital mortality was 7 (13%) in both groups combined (5 for patients with IRAA and 2 for ILAA). In conclusion, the surgical management of HS is associated with satisfactory outcomes in current era.

Outcomes of Single Ventricle Patients Undergoing the Kawashima Procedure: Can We Do Better?

Objectives:

Current technology advances in virtual surgery modeling and computational flow dynamics allow preoperative individualized computer-based design of Fontan operation. To determine potential role of those innovations in patients undergoing hepatic vein incorporation (HVI) following Kawashima operation, we retrospectively examined historic cohort of patients who underwent HVI following Kawashima with focus on regression of pulmonary arteriovenous malformations (PAVMs).

Methods:

Twenty-two children with single ventricle and interrupted inferior vena cava underwent Kawashima operation (2002-12). Twenty-one (96%) patients had left atrial isomerism and 21 (96%) had undergone prior first-stage palliation. Clinical outcomes were examined.

Results:

Mean O2 saturation (SaO2) increased from 77% ± 8% to 85% ± 6% ( P = .002) after Kawashima. Fifteen (68%) patients developed PAVMs. Eighteen patients underwent HVI (median age and interval from Kawashima: 4.4 and 3.7 years, respectively). Mean SaO2 prior to HVI was 77% ± 8% and increased to 81% ± 10% at the time of hospital discharge ( P = .250), with five patients requiring home oxygen. On follow-up, mean SaO2 increased to 95% ± 4% ( P < .001). Overall ten-year survival following Kawashima was 94%.

Conclusions:

A large number of patients develop PAVMs and subsequent cyanosis after Kawashima operation. Early following HVI, SaO2 is commonly low and insignificantly different from that prior to HVI. Although SaO2 will improve on follow-up in most patients, a number of patients continue to have low saturations, indicating incomplete resolution of PAVMs. Given the heterogeneity of those patients and lack of preoperative predictors for complete PAVM regression, our findings suggest a role for virtual surgery to determine optimal individual procedure design that would provide even distribution of hepatic blood flow to both pulmonary arteries.

Kawashima by Fenestrated Hemi-Fontan for Palliation Following Prior Stage I Norwood Operation

Single ventricle patients with interrupted inferior vena cava (IVC) and azygos continuation to the superior vena cava (SVC) are typically palliated with a bidirectional cavopulmonary shunt (BCPS), known as the Kawashima operation in this setting. Because the volume of venous blood directed to the pulmonary arteries is substantially greater in the presence of interrupted IVC, Kawashima procedures are commonly delayed to older age compared to other single ventricle patients undergoing BCPS. We report two young infant single ventricle patients with interrupted IVC and azygos continuation to the SVC who underwent stage I Norwood procedures for initial palliation. In both cases, a fenestrated hemi-Fontan procedure achieved successful Kawashima circulations.

Neovasculature can be induced by patching an arterial graft into a vein: A novel in vivo model of spontaneous arteriovenous fistula formation

Arteriovenous malformations consist of tangles of arteries and veins that are often connected by a fistula. The causes and mechanisms of these clinical entities are not fully understood. We discovered that suturing an arterial patch into the common jugular vein of rabbits led to spontaneous neovascularization, the formation of an arteriovenous fistula and the development of an arteriovenous shunt. An arterial patch excised from the common carotid artery was sutured into the common jugular vein. Within a month, a dense nidus-like neovasculature formed around the patch. Angiography and pulse-oximeter analyses showed that the blood flowing into the neovasculature was arterial blood. This indicated that an arteriovenous shunt had formed. Fluorescence in situ hybridization with a Y chromosome probe in female rabbits that received an arterial patch from male rabbits showed that the vessels close to the graft bore the Y chromosome, whereas the vessels further away did not. Enzyme-linked immunosorbent assays and cDNA microarray analysis showed that multiple angiogenic factors were upregulated after patch transplantation. This is the first in vivo model of spontaneous arteriovenous fistula formation. Further research on these differences may help to improve understanding of human vascular anomaly diseases and the basic principles underlying vasculogenesis and/or angiogenesis.

The Outcomes of Superior Cavopulmonary Connection Operation: a Single Center Experience

Introduction

The superior cavopulmonary connection operation is one of the stages of the palliative surgical management for patients with functionally single ventricle. After surviving this stage, the patients are potential candidates for the final palliative procedure: the Fontan operation.

Objectives

This study aimed to analyze the outcomes of superior cavopulmonary connection operations in our center and to identify factors affecting the survival and the progression to Fontan stage.

Methods

The outcomes of 161 patients were retrospectively analyzed after undergoing superior cavopulmonary connection operation in our center between 2005 and 2015.

Results

The early mortality rate was 2.5%. Five (3.1%) patients underwent takedown of the superior cavopulmonary connection. The rate of exclusion from the Fontan stage was 8.3%. Statistical analysis revealed that elevated mean pulmonary artery pressure preoperatively and the prior palliation with pulmonary artery banding were risk factors for both early mortality and takedown; however, the age, the morphology of the single ventricle and the type of operation were not considered risk factors.

Conclusion

The superior cavopulmonary connection operation can be performed with low rate mortality and morbidity; however, the elevated mean pulmonary artery pressure preoperatively and the prior pulmonary artery banding are associated with poor outcomes.

Percutaneous Transhepatic Fontan-Kreutzer Completion of Hepatic Vein Inclusion

We report the case of an 11-year-old girl with heterotaxy syndrome, dextrocardia, and azygos continuation of an interrupted inferior vena cava who had developed pulmonary arteriovenous fistulas after a Kawashima procedure consisting of bilateral superior cavopulmonary anastomoses. She presented with profound cyanosis, fatigue, and failure to thrive. An operative procedure to direct hepatic vein effluent to the pulmonary circulation was performed with placement of an extracardiac conduit between the hepatic veins and the left pulmonary artery. Persistence of cyanosis led to investigation, which led to the discovery of an unintentionally excluded right hepatic vein. A percutaneous transhepatic catheter intervention was performed in which a vascular plug was implanted to occlude the "missed" right hepatic vein, redirecting the flow through intrahepatic venovenous channels to the conduit. Clinical condition and arterial oxygen saturation were substantially improved one year after the two-step hepatic vein inclusion procedure.

Hepatoazygos venous shunt for Fontan completion after Kawashima operation

Fontan completion after prior Kawashima repair for single ventricle with interruption of the inferior vena cava can be accomplished by various methods. We describe a patient who underwent the connection of hepatic to hemiazygos vein that we believe would be superior to the conventional cavopulmonary connection in our patient.

Impact of Era, Type of Isomerism, and Ventricular Morphology on Survival in Heterotaxy: Implications for Therapeutic Management

BACKGROUND

Heterotaxy has been demonstrated to reduce survival. There are several different subgroups of patients, however, and no single study has had a large number of patients and analyzed survival across the different subgroups such as patients born in different eras, patients with right and left isomerism, and patients with biventricular or functionally univentricular hearts. This study pools previously reported data from Kaplan-Meier curves and performs such subgroup analysis.

METHODS

A systematic review of the literature was performed to identify studies reporting survival of patients with the so-called "heterotaxy" by means of Kaplan-Meier survival curves. Data were extracted from these survival curves and then pooled together. A polynomial regression was then used to generate a pooled survival curve. This was done for all patients, those born in a more recent era, those with right and left isomerism, and those with biventricular or functionally univentricular hearts.

RESULTS

Those born in the more recent era (after 2000) had increased survival compared to the overall cohort. Those with left isomerism tended to have a survival benefit compared to those with right isomerism until about 16 years of age, beyond which those with right isomerism developed a survival benefit. Those with biventricular hearts had a survival benefit compared to those with left isomerism.

CONCLUSION

Survival in the so-called heterotaxy syndrome is based on several factors, which include era of birth, sidedness of isomerism, and whether the heart is biventricular or functionally univentricular.

Arterial desaturation due to pulmonary arteriovenous malformations after the Kawashima Operation

Arterial desaturation may occur after the Kawashima procedure and, in the absence of venovenous collaterals is usually due to pulmonary arteriovenous malformations. Stenting of the pulmonary arteries, oxygen therapy, and pulmonary vasodilators such as sildenafil have not been able to resolve the arterial desaturation and the only way to do this has been Fontan completion. The time course of the formation of these malformations after the Kawashima and the progression of cyanosis and its resolution after the Fontan has only been demonstrated in case reports and small case series. We pool the available data to model arterial saturations in patients with pulmonary arteriovenous malformations after the Kawashima procedure.

Eponymous cardiovascular surgeries for congenital heart diseases--imaging review and historical perspectives

Advances in pediatric cardiology and cardiac surgical techniques over the past few decades have revolutionized the management of the patients with congenital heart disease, and many now survive into adulthood. Several eponymous surgical procedures performed for congenital heart disease have been named after eminent surgeons. In this article, we provide a short biography of the surgeons associated with these eponymous surgical procedures along with their other important scientific contributions. This is followed by a review of these surgical procedures and their most common complications. Imaging appearances of these surgical procedures along with common complications are described and illustrated, with particular emphasis on magnetic resonance imaging. The surgical procedures described in this review include Blalock-Taussig, Potts, Waterston, Glenn, Fontan, Kawashima, Norwood, Sano, Damus-Kaye-Stansel, Mustard, Senning, Jatene, LeCompte, Rastelli, Rashkind, Ross, and Waldenhausen.

High incidence of abdominal venovenous collaterals after Kawashima operation

INTRODUCTION

Systemic venous collaterals have been found at different stages of single-ventricle palliation, specifically after Kawashima operation. In this study, we present the incidence, clinical features, associated risk factors, and management of such venovenous collaterals (VVCs) after Kawashima procedure.

MATERIALS AND METHODS

A retrospective review of all the patients who underwent Kawashima procedure prior to December 2011 at Hamad General Hospital, Qatar, was performed. Data were collected and reviewed from medical records.

RESULTS

The study group involved a total of six patients with Kawashima procedure. The median age of patients was 112.7 months (range 46-336 months), and median age at the time of Kawashima operation was 31.7 months (range 15-187 months). Mean systemic arterial oxygen saturation (Spo 2) after Kawashima operation was 94.5% ± 1.5%. In five patients, during a median follow-up of 53.4 months (range 16.9-147.9 months), the Spo 2 declined to a mean of 78.8% ± 8.2%. A total of 16 venous collaterals were observed in the study group, and majority (70%) of these collaterals were subdiaphragmatic.

CONCLUSION

In our study, abdominal VVCs were observed in 100% of the patients who were followed after Kawashima operation. We therefore recommend that thorough evaluation for such VVCs should be part of the ongoing evaluation of patients after Kawashima operation, especially in those with low Spo 2. We also recommend early surgical rerouting of hepatic veins to pulmonary arteries in all post-Kawashima patients.

Pulmonary vascular diseases

Diseases of the pulmonary vasculature are a cause of increased pulmonary vascular resistance (PVR) in pulmonary embolism, chronic thromboembolic pulmonary hypertension (CTEPH), and pulmonary arterial hypertension or decreased PVR in pulmonary arteriovenous malformations on hereditary hemorrhagic telangiectasia, portal hypertension, or cavopulmonary anastomosis. All these conditions are associated with a decrease in both arterial PO2 and PCO2. Gas exchange in pulmonary vascular diseases with increased PVR is characterized by a shift of ventilation and perfusion to high ventilation-perfusion ratios, a mild to moderate increase in perfusion to low ventilation-perfusion ratios, and an increased physiologic dead space. Hypoxemia in these patients is essentially explained by altered ventilation-perfusion matching amplified by a decreased mixed venous PO2 caused by a low cardiac output. Hypocapnia is accounted for by hyperventilation, which is essentially related to an increased chemosensitivity. A cardiac shunt on a patent foramen ovale may be a cause of severe hypoxemia in a proportion of patients with pulmonary hypertension and an increase in right atrial pressure. Gas exchange in pulmonary arteriovenous malformations is characterized by variable degree of pulmonary shunting and/or diffusion-perfusion imbalance. Hypocapnia is caused by an increased ventilation in relation to an increased pulmonary blood flow with direct peripheral chemoreceptor stimulation by shunted mixed venous blood flow.

Normal and abnormal pulmonary arteriovenous shunting: occurrence and mechanisms

Severe cyanosis due to pulmonary arteriovenous fistulas occurs often after a bidirectional superior cavopulmonary anastomosis (Glenn operation) and also in some congenital anomalies in which hepatic venous blood bypasses the lungs in the first passage. Relocation of hepatic flow into the lungs usually causes these fistulas to disappear. Similar pulmonary arteriovenous fistulas are observed in hereditary haemorrhagic telangiectasia, and in liver disease (hepatopulmonary syndrome). There is no convincing identification yet of a responsible hepatic factor that produces these lesions. Candidates for such a factor are reviewed, and the possibility of angiotensin or bradykinin contributing to the fistulas is discussed.

Progressive cyanosis following Kawashima operation: slow resolution after redirection of hepatic veins

Progressive cyanosis often develops following Kawashima operation in patients with left atrial isomerism, interrupted inferior vena cava and hepatic veins draining to the atria. Knowledge on the timing and extend of resolution following hepatic venous redirection is sparse. A girl developed progressing cyanosis following Kawashima operation at the age of ten months. Arterial oxygen saturations at rest dropped to 60-65%. Surgical redirection of hepatic veins into the cavopulmonary circulation at the age of three years had no immediate effect. However, arterial oxygen saturations increased gradually over nine months to 90-93% and 95-100% after three years.

Superior cavopulmonary anastomosis timing and outcomes in infants with single ventricle

OBJECTIVES

We sought to identify factors associated with the timing and surgical outcomes of the superior cavopulmonary anastomosis.

METHODS

The Pediatric Heart Network's Infant Single Ventricle trial database identified participants who underwent superior cavopulmonary anastomosis. Factors potentially associated with age at superior cavopulmonary anastomosis, length of stay and death by 14 months of age were evaluated. Factors included subject demographics, cardiac anatomy, measures from neonatal hospitalization and pre-superior cavopulmonary anastomosis visit, adverse events, echocardiographic variables, intraoperative variables, superior cavopulmonary anastomosis type, and number of concurrent cardiac surgical procedures. Age at superior cavopulmonary anastomosis was analyzed using Cox proportional hazards regression. Natural log length of stay was analyzed by multiple linear regression.

RESULTS

Superior cavopulmonary anastomosis was performed in 193 subjects at 5.2 months of age (interquartile range, 4.2, 6.2) and weight of 5.9 kg (interquartile range, 5.3, 6.6). The median length of stay was 7 days (interquartile range, 6, 10). There were 3 deaths and 1 transplant during the superior cavopulmonary anastomosis hospitalization, and 3 deaths and 3 transplants between discharge and 14 months of age. Age at superior cavopulmonary anastomosis was associated with center and interstage adverse events. A longer length of stay was associated with younger age and greater case complexity. Superior cavopulmonary anastomosis type, valve regurgitation, ventricular ejection fraction, and ventricular end-diastolic pressure were not independently associated with age at superior cavopulmonary anastomosis or the length of stay.

CONCLUSIONS

Greater case complexity and more frequent interstage adverse events are associated with an earlier age at superior cavopulmonary anastomosis. Significant variation in age at superior cavopulmonary anastomosis among centers, independent of subject factors, highlights a lack of consensus regarding the optimal timing. Factors associated with length of stay could offer insights for improving presuperior cavopulmonary anastomosis care and surgical outcome.

Extracardiac complications of the Fontan circuit

The Fontan operation is the primary surgical procedure used in the palliation of patients with univentricular cardiac physiology. With improved survival of children with congenital heart disease, long-term complications of the Fontan circuit are being encountered more frequently. Radiologists are more likely to see both the cardiac and extracardiac complications of the Fontan circuit. Awareness of the common extracardiac complications in children with failing Fontan circuits will aid the radiologist in making the appropriate diagnosis and guide the cardiologist caring for these patients.

Reconstruction of cavopulmonary pathway for the patient with persistent arteriovenous malformations due to offset flow from hepatic vein

The hypoxemia caused by arteriovenous malformations after cavopulmonary shunt in patients with heterotaxy, an interrupted inferior vena cava and single ventricle physiology have been treated by incorporation of hepatic vein flow into the pulmonary circulation. However, some patients have persistent arteriovenous malformations because of offset hepatic venous flow to one pulmonary artery. Various approaches have been used to change offset flow to achieve balanced hepatic flow to the lungs in this patient population. This case report highlights the challenges that may be associated with anastomosis of the azygos vein to the inferior vena cava at the level of the diaphragm and illustrates an alternative technique to direct hepatic venous blood into an affected lung with arteriovenous malformations. The redirection of hepatic venous flow to the affected pulmonary artery resulted in resolution of symptoms within months of surgery.

Surgical Management of the Neonate With Heterotaxy and Long-Term Outcomes of Heterotaxy

A review of the many challenges facing the neonate with heterotaxy has identified total anomalous pulmonary venous connection, atrioventricular valve abnormalities, pulmonary atresia, and arrhythmias including heart block as particular risk factors for the child who will pursue a single-ventricle pathway. Experience varies widely between different centers as to the percentage of patients who are suitable for biventricular repair, ranging from less than 20% to greater than 50%. Biventricular repair may only require simple baffling of anomalous systemic or pulmonary veins or may involve complex intraventricular baffle repair of double-outlet right ventricle with common atrioventricular valve. The long-term complications of heterotaxy include accelerated development of pulmonary arteriovenous malformations after the Kawashima procedure, high mortality and morbidity for the Fontan procedure (although improving results have been reported more recently), and the development of late arrhythmias. Extracardiac problems include a high risk of volvulus if malrotation is present, suggesting the need for an elective Ladd procedure. The presence of associated ciliary dyskinesia appears to be associated with an increased risk of postoperative morbidity, particularly ventilator dependence and other respiratory complications. The child with heterotaxy faces many challenges that are often underappreciated by both caregivers and families.

Pulmonary Arteriovenous Malformations in Heterotaxy Syndrome

We report a surgical approach using hepatic vein–to–azygos vein connection without cardiopulmonary bypass or deep hypothermic circulatory arrest in a patient with heterotaxy syndrome and interrupted inferior vena cava with persistence of pulmonary arteriovenous malformations (PAVMs) after previous Fontan completion. We advocate early performance of hepatic vein–to–azygos vein connection following the Kawashima operation for heterotaxy with functionally univentricular heart and interrupted inferior vena cava. We review the physiology of heterotaxy syndrome with congenital heart disease and justify our approach in the context of a review of previous surgical strategies used in this patient population.

Intraatrial baffle repair of anomalous systemic venous return without hepatic venous drainage in heterotaxy syndrome

A 7-month-old boy with heterotaxy syndrome had partial atrioventricular septal defect and interrupted inferior vena cava with hemiazygos continuation to a left superior vena cava. The left side of the common atrium receiving all the venous drainage was in connection with the left ventricle and the aorta. The small atrium and the proximity of the pulmonary and hepatic vein orifices precluded complete baffling. This report describes an intraatrial baffle repair of anomalous systemic venous return without hepatic venous drainage. This resulted in good oxygenation postoperatively, with oxygen saturation ranging from 93% to 98%.

Venovenous malformation: a common finding after Kawashima operation

OBJECTIVES

It has been reported that systemic venovenous malformation (VVM) can develop in patients with interrupted inferior vena cava (IVC) and univentricular type of congenital heart disease who undergo superior vena cava to pulmonary artery connection (Kawashima operation). These malformations can lead to profound systemic desaturation postoperatively. However, there have been few reports that characterise the prevalence, anatomic details and clinical correlations of these systemic VVM arising after Kawashima operation. In this study, we describe our experience with VVM after Kawashima operation, and discuss issues regarding their evaluation and postoperative management.

METHODS

Eight patients with median age 19 months (range: 5-238) who underwent Kawashima operation were subjected to postoperative angiography, prospectively. Sites of VVM origin and entry, as well as their course, were documented. The presence of pulmonary arteriovenous malformations (AVMs) was also documented.

RESULTS

At median follow-up of 31 months (range: 16-72 months), a total of 14 VVM were found in different supra- and infra-diaphragmatic sites in six patients (75%); four of them had concomitant pulmonary AVM while the remaining two patients had only pulmonary AVM.

CONCLUSIONS

Our findings suggest that systemic VVM can occur frequently after Kawashima operation and can produce significant desaturation postoperatively, and hence we support hepatic incorporation. Performing detailed angiographic studies of the supra- and infra-diaphragmatic systemic veins in routine assessment of patients before Kawashima operation is, probably, warranted.

Congenitally corrected transposition of the great arteries: a unique case from Iraq

A severely cyanotic 27-month-old Iraqi child was transferred to the United States for surgical treatment of suspected tetralogy of Fallot. Her diagnostic studies showed dextrocardia, congenitally corrected transposition of the great arteries, hypoplastic left-sided ventricle, interrupted inferior vena cava, and severe pulmonic stenosis. Given the anatomic constraints as well as the absence of long-term medical care, the decision was made to pursue single-ventricle palliation. The patient recovered from a superior cavopulmonary anastomosis without event and has since returned to her native Iraq.

CT findings in unilateral hepatopulmonary syndrome after the Fontan operation

BACKGROUND

Patients with complex congenital heart defects palliated by connecting the systemic veins directly to the pulmonary circulation are known to develop hepatopulmonary syndrome (HPS). Although rare, HPS can develop following the Fontan operation.

OBJECTIVE

To present and analyse the CT findings of HPS in patients with a Fontan circulation.

MATERIALS AND METHODS

From May to December 2005, six patients with HPS following the completion of a Fontan circulation were evaluated. CT findings were reviewed and were compared with angiographic findings.

RESULTS

All six patients showed unilateral involvement. All patients except one had inferior vena cava (IVC) interruption with azygos continuation. CT scans showed abnormal vascular dilatation in one lung, and properly demonstrated the anatomy causing the hepatic venous blood to flow preferentially into one lung. These CT findings correlated well with the angiography findings.

CONCLUSION

HPS that develops after the Fontan procedure is typically unilateral and is often associated with IVC interruption and azygos or hemiazygos continuation. CT demonstrates dilatation of pulmonary vessels in the affected lung and may be able to demonstrate the underlying anatomical cause for the predilection of hepatic venous flow to the contralateral lung.

Rational approach to surgical management of complex forms of double outlet right ventricle with modified Fontan operation

OBJECTIVE

Surgical alternatives to biventricular repair of complex forms of double outlet right ventricle (DORV) remain controversial. The available knowledge of the Fontan operation (FO) for children with this anomaly is limited. The aim of this report is to analyze the results and risk factors of the FO performed as an alternative to the biventricular repair of complex DORV.

METHODS

Between 1980 and 2007, 47 patients with complex forms of DORV underwent a modified FO. Concomitant defects included noncommitted, subpulmonary or multiple ventricular septal defects, anomalies of atrioventricular valves and/or caval veins, and ventricular hypoplasia. Thirty-five of 45 patients (77%) have undergone a hemi-Fontan and 35 patients (77%; 10 children without previous hemi-Fontan) have had a completion FO without mortality or Fontan takedown. Risk factors for adverse outcomes were determined by multivariate analyses.

RESULTS

There were no early but six late deaths. The follow-up period ranged from 1 year to 25 years (mean 10.0 +/- 6.5). The actuarial survival was 93% at 1 year, 87% at 10, 15, and 25 years. Multivariate analysis identified preoperative left or common atrioventricular valve insufficiency (P = .001) and decreased left ventricular ejection fraction (<50%) (P = .02) as risk factors for late death and/or morbidity. The only risk factor for a late adverse outcome and poor functional status was increased preoperative pulmonary vascular resistance (>4.0 Woods units/m(2)) (P = .005).

CONCLUSION

FO provides good early- and mid-term results in the treatment of complex forms of DORV. The increased preoperative pulmonary vascular resistance was a significant negative risk factor for adverse outcome in this patient population.

Management of systemic venous anomalies in the pediatric cardiovascular surgical patient

Systemic venous anomalies are rare and heterogeneous entities. Although these anomalies are rare in the general population, they occur more frequently in the subpopulation with congenital heart disease. In and of themselves, most of these lesions have no physiologic significance. However, in the setting of congenital heart disease these lesions may significantly alter surgical treatment. This review is dedicated to these lesions.