Evaluation and Management of the Child and Adult With Fontan Circulation: A Scientific Statement From the American Heart Association

Management of Fontan circulation in pregnancy: a multidisciplinary approach to care

The Fontan operation was first performed in 1968 and is a palliative procedure for children born with single ventricle forms of congenital heart disease. Today, 70,000 patients worldwide have Fontan circulation today, half of them women, and with an expected 30-year survival of >80%, this population is expected to double in the next 20 years. The Fontan operation surgically redirects systemic venous blood return directly to the pulmonary circulation, bypassing the single ventricle. This abnormal anatomy results in significant challenges for the cardiovascular system and is marked by a sustained, abnormally elevated systemic venous pressure combined with decreased cardiac output. As more women with Fontan circulation reach childbearing age, understanding the unique risks of pregnancy to the mother and fetus and how to best provide clinical care for these women during pregnancy is imperative. However, there are limited clinical data to guide counseling and management in this population. This expert review offers an analysis of the literature about Fontan circulation during pregnancy and describes our center's current multidisciplinary approach to care for these women in the preconception, antepartum, intrapartum, and postpartum periods.

Cardiovascular and abdominal flow alterations in adults with morphologic evidence of liver disease post Fontan palliation

BACKGROUND

Although morphologic abnormalities in the liver are commonly encountered post Fontan palliation, the relationships between hepatic morphology, vascular flows, and clinical status remain incompletely understood. We therefore aimed to explore flow characteristics in hepatic and intestinal vessels and to examine cardiovascular associations with liver disease.

METHODS

This was a retrospective study of adults post Fontan palliation undergoing clinically indicated cardiovascular magnetic resonance imaging (MRI). Patients were included if MRI flow quantification was available for cardiac, hepatic and intestinal vessels; patients were excluded if phase-contrast flow imaging was insufficient for analysis.

RESULTS

Thirty patients were studied (median age at MRI 28.5 years [range 19-47]). Eighteen subjects (60%) were classified as having morphologic liver disease according to validated criteria based on available MRI imaging. Abdominal and cardiovascular flows were quantified. Patients with morphologic liver disease had a 41% reduction in superior mesenteric artery (211 ± 124 versus 358 ± 181 mL/min/m², p = .004), a 36% reduction in hepatic vein (496 ± 247 versus 778 ± 220 mL/min/m², p = .01), a 31% reduction in portal vein (399 ± 133 versus 580 ± 159 mL/min/m², p = .004), and an 18% reduction in Fontan pathway flows (1358 ± 429 versus 1651 ± 270 mL/min/m², p = .04) compared with the remaining population. Adverse cardiovascular events were not associated with morphologic liver disease.

CONCLUSION

Morphologic liver disease appears to be associated with flow alterations within the heart, liver and intestine post Fontan palliation. These novel observations suggest that a potential relationship exists between morphologic disease and vascular flows thereby providing further insights into the pathophysiology of liver disease in this high-risk population.

Diagnosis and Management of Lymphatic Disorders in Congenital Heart Disease

Purpose of Review

Lymphatic disorders have received an increasing amount of attention over the last decade. Sparked primarily by improved imaging modalities and the dawn of lymphatic interventions, understanding, diagnostics, and treatment of lymphatic complications have undergone considerable improvements. Thus, the current review aims to summarize understanding, diagnostics, and treatment of lymphatic complications in individuals with congenital heart disease.

Recent Findings

The altered hemodynamics of individuals with congenital heart disease has been found to profoundly affect morphology and function of the lymphatic system, rendering this population especially prone to the development of lymphatic complications such as chylous and serous effusions, protein-losing enteropathy and plastic bronchitis.

Summary

Although improved, a full understanding of the pathophysiology and targeted treatment for lymphatic complications is still wanting. Future research into pharmacological improvement of lymphatic function and continued implementation of lymphatic imaging and interventions may improve knowledge, treatment options, and outcome for affected individuals.

Thromboembolic complications in adult congenital heart disease: the knowns and the unknowns

Despite impressive improvement in long-term survival, adults with congenital heart disease (CHD) remain exposed to a significant cardiovascular morbidity over lifetime. Thromboembolic events (TE) are a major issue. Specific anatomic groups have been shown a particular high risk of TE, including cyanotic heart disease and Fontan circulation. Many intercurrent clinical factors add a substantial risk such as intracardiac medical devices, atrial arrhythmia, endocarditis, or pregnancy. Nevertheless, what is unknown exceeds what is known, especially regarding the management of this heterogenous patient population. Anticoagulation decision should always be individualized weighing balanced with the alternative risk of hemorrhagic complications. In this review, we aim to synthetize existing literature on TE in adults with CHD, discuss management issues, highlight gaps in knowledge, and intend to suggest high priority research.

Imaging of Fontan-associated liver disease

The Fontan operation has dramatically altered the natural history of functionally single ventricle congenital heart disease. Patients who have undergone the Fontan operation are living longer and, thus, noncardiac morbidity resulting from the Fontan operation is increasingly being recognized. Fontan-associated liver disease (FALD), one of the chief morbidities following the Fontan operation, is believed to be a multifactorial process that manifests as hepatic congestion and fibrosis, portal hypertension, and development of focal liver lesions, including malignant tumors. This article reviews the imaging findings of FALD in the pediatric and young adult population, reviews the literature related to the imaging of FALD and discusses possible screening algorithms for this population. The need for further research to better understand the causes of FALD, to establish if early liver stiffness measurements (or their change over time) predict long-term outcomes and complications, and to define optimal liver screening procedures is highlighted.

Gastrointestinal neuroendocrine tumors in Fontan patients

The Fontan procedure used for palliation of single ventricle physiology is associated with multisystemic morbidity. With improving survival and increased use of surveillance imaging in this patient population, long-term complications associated with Fontan circuits are commonly encountered by radiologists. One interesting observation is the apparent increased risk of paragangliomas and pheochromocytomas in this group of patients and perhaps a pathogenetic role of chronic hypoxia. We report 2 cases of gastrointestinal neuroendocrine tumors (NET) in the setting of Fontan circuit. The first is a 20-year-old female with history of hypoplastic left heart and Fontan palliation who presented with hematochezia and was diagnosed with a jejunal grade 2 NET. The second case is of a 12-year-old boy with history Fontan palliation for single ventricle physiology, incidentally found to have a well-differentiated pancreatic NET during precardiac transplant workup. These cases should alert the radiologists to be aware of the apparent association between Fontan procedure and NET.

Thoracic duct decompression and jugular vein banding-an effective treatment option for protein-losing enteropathy and plastic bronchitis in severe failing Fontan circulation: a case report

Background

Plastic bronchitis (PB) and protein-losing enteropathy (PLE) are devastating complications after Fontan palliation that lead to uncontrolled loss of protein-rich lymphatic fluid into extra lymphatic compartments. Decompression of the thoracic duct is a new treatment option that effectively restores lymphatic system integrity by redirecting lymphatic flow into the low-pressure levels of the common atrium.

Case summary

We report a patient with severe failing Fontan circulation where surgical thoracic duct decompression leads to resolution of PLE and PB symptoms but worsening hypoxaemia that could be managed with banding of internal jugular vein.

Discussion

Thoracic duct decompression in patients with failing Fontan circulation can be a simple and effective treatment for PLE and PB. Hypoxaemia may occur but can be managed with banding of internal jugular vein.

Perioperative Considerations for the Fontan Patient Requiring Noncardiac Surgery

Children and adults with congenital heart disease undergoing noncardiac surgery are at higher risk of perioperative adverse events. Patients have significant comorbidities and syndromic associations that increase perioperative risk further. The complexity of congenital heart disease requires a thorough understanding of lesion-specific pathophysiology in order to provide safe care. Comprehensive multidisciplinary planning and the use of skilled and experienced teams achieve the best outcomes. The anesthesiologist is a perioperative physician charged with providing safe anesthesia care, instituting appropriate hemodynamic monitoring, and determining appropriate postoperative disposition on an individual basis.

Heart transplantation at a single tertiary adult congenital heart disease centre: Too little, too late?

BACKGROUND

Heart failure (HF) is the leading cause of death in adults with congenital heart disease (ACHD). Heart transplantation can be an effective therapy for them, albeit unfavourable anatomy, end-organ damage, pulmonary vascular disease, HLA sensitization and lack of robust selection criteria currently limit its application.

METHODS

Consecutive CHD patients considered for heart or combined heart and lung transplantation at our tertiary ACHD centre between 2000 and 2018 constitute our study population. Baseline characteristics and outcome, including transplantation and death, were obtained for all patients from designated databases, medical records and the UK Office for National Statistics.

RESULTS

From a total of more than 9000 active ACHD patients under follow-up, 166 (median age 40.4 years) fulfilled inclusion criteria, with a broad spectrum of underlying diagnosis: univentricular heart 22.3%, systemic right ventricle 22.3%, systemic-to-pulmonary shunts and Eisenmenger syndrome 16.3%, left sided valvular lesions 14.5%, tetralogy of Fallot 12.7%, CHD associated with cardiomyopathy 4.8% and other 7.2%. There was a high overall mortality with 39.2% of patients dying over a median follow-up of 2.7 years. A minority of patients (22.9%) were eventually listed and only 13.3% from the 166 patients were actually transplanted. Survival at 1 year after transplantation was 81.8% and remained high long-term (65.5% at 15 years). We describe herewith in detail characteristics and outcome of our cohort and present the transplantation pathway followed.

CONCLUSION

Of the small number of patients with ACHD considered for heart transplantation at a large tertiary centre, there was high overall mortality, with only a fraction of patients being actually transplanted. Patients who received transplantation, however, had a good outcome. Better patient selection and timing are clearly warranted so that more ACHD patients are considered and potentially benefit from this effective form of therapy.

Early development of hepatic fibrosis after Fontan procedure: A non-invasive study of a subclinical liver disease

BACKGROUND

To evaluate subclinical liver fibrosis after Fontan procedure using a comprehensive method that reflects the overall liver status rather than the focal biopsy lesion.

METHOD

This cross-sectional study included 66 patients without symptoms of liver disease who had at least 5 years of elapsed time since the Fontan procedure (time since Fontan procedure 17.5 ± 7.3 years). Serum enhanced liver fibrosis (ELF) scores and 2D shear wave elastography (SWE), which are expected to detect liver fibrosis earlier than liver enzyme tests and ultrasonography, were evaluated along with general examinations.

RESULTS

Liver cirrhosis diagnosed by ultrasonography showed a marked increase 16 years after surgery (elapsed time: 6-15 years since Fontan, 43.8%; 16-25 years, 70.8%; 26-35 years, 90.0%). The age-adjusted ELF score and liver stiffness according to SWE were elevated during the early postoperative period (6-15 years since Fontan). In adulthood (elapsed time > 16 years), the adjusted ELF score was correlated with liver stiffness (r = 0.514, p = .009) and liver enzyme levels. There was no correlation between liver fibrosis and the Fontan palliation type. AST to platelet count ratio and FIB-4, which are non-invasive fibrosis markers, presumed absence of fibrosis in approximately 90% of patients.

CONCLUSIONS

In the evaluation of early liver fibrosis after the Fontan procedure, abnormal findings of 2D SWE and ELF scores were observed before abnormal ultrasound and liver enzyme results. Therefore, these indicators may be helpful for the diagnosis of early liver fibrosis, and further longitudinal study might be needed.

Protein-losing enteropathy and plastic bronchitis after the Fontan procedure

OBJECTIVES

Protein losing enteropathy and plastic bronchitis are severe complications in Fontan circulation, with 5-year survival ranging from 46% to 88%. We report risk factors and outcomes of protein losing enteropathy and plastic bronchitis in patients undergoing the Fontan.

METHODS

We performed a retrospective analysis of 1561 patients from the Australia New Zealand Fontan Registry. Two end points were death and cardiac transplantation examined with Cox regression (if no competing risks) or cumulative incidence curves and cause-specific Cs regression.

RESULTS

A total of 55 patients with protein losing enteropathy/plastic bronchitis were included. Their median age at the Fontan was 5.7 years, and time to onset after the Fontan for protein losing enteropathy was 5.0 years and plastic bronchitis was 1.7 years. Independent predictors for developing protein losing enteropathy/plastic bronchitis were right-ventricular morphology with hypoplastic left-heart syndrome (hazard ratio, 2.30; confidence interval, 1.12-4.74), older age at Fontan (hazard ratio, 1.13; confidence interval, 1.03-1.23), and pleural effusions after Fontan (hazard ratio, 2.43; confidence interval, 1.09-5.41); left-ventricular morphology was protective (hazard ratio, 0.36; confidence interval, 0.18-0.70). In the protein losing enteropathy/plastic bronchitis population, freedom from death or transplantation after protein losing enteropathy/plastic bronchitis diagnosis at 5, 10, and 15 years was 70% (confidence interval, 58-85), 65% (confidence interval, 51-83), and 43% (confidence interval, 26-73), respectively; only older age (hazard ratio, 1.23; confidence interval, 1.01-1.52) was an independent predictor. Twenty-six surgical interventions were performed in 20 patients, comprising Fontan revisions (n = 5), fenestrations (n = 11), Fontan conversions (n = 5), atrioventricular valve repairs (n = 3), and hepatic vein diversion (n = 2).

CONCLUSIONS

Protein losing enteropathy and plastic bronchitis remain severe complications, preferably affecting patients with dominant right single ventricle, with older age at Fontan being a predictor of developing protein losing enteropathy/plastic bronchitis and poorer prognosis. Heart transplantation remains the ultimate treatment, with 30% dying or requiring transplantation within 5 years, and the remaining being stable for long periods.

The Evolving Surgical Burden of Fontan Failure: An Analysis of The Society of Thoracic Surgeons Congenital Heart Surgery Database

BACKGROUND

Fontan failure often requires surgical therapy in the form of Fontan revision or heart transplantation. We sought to characterize national trends in the surgical burden of Fontan failure and identify risk factors for adverse outcomes.

METHODS

Fontan patients undergoing Fontan revision or transplantation from January 2010 to June 2018 were included. We evaluated baseline characteristics and outcomes and used multivariable logistic regression to identify risk factors for operative mortality and composite mortality and major morbidity.

RESULTS

A total of 1135 patients underwent Fontan revision (n = 598) or transplantation (n = 537) at 100 centers. Transplantations increased from 34 in 2010 to 76 in 2017, largely owing to an increase in patients with hypoplastic left heart syndrome (HLHS) (18 in 2010 to 49 in 2017), while Fontan revision decreased (75 in 2010 to 49 in 2017). Transplantation patients were younger (median 14 years of age vs 18 years of age; P < .001), more often had preoperative risk factors (66% vs 40%; P < .001), and more often had HLHS (51% vs 15%; P < .001). Operative mortality and composite major morbidity and mortality were 7.6% and 35% for transplantation and 7.1% and 22% for Fontan revision, respectively. Multivariable risk factors for mortality included older age (odds ratio [OR], 1.08/y; P = .007), presence of preoperative risk factors (OR, 3.33; P = .002), and concomitant pulmonary artery reconstruction (OR, 2.7; P = .029) for Fontan revision but only older age (OR, 1.06/y; P = .020) for transplantation.

CONCLUSIONS

Both transplantation and Fontan revision are associated with high morbidity and mortality. There has been evolution of practices in surgical therapy for Fontan failure, perhaps related to rising prevalence of HLHS staged palliation.

Scimitar syndrome: A new multipatch technique and incidence of postoperative pulmonary vein obstruction

Objective

A review of our center's experience before March 2011 showed that one half of 36 patients who had a baffling or reimplantation procedure to repair scimitar syndrome developed pulmonary vein obstruction. We analyzed the results of a new operation that enlarges the left atrium and avoids circuitous pathways or tension on the scimitar pulmonary vein.

Methods

Between April 2011 and November 2018, 22 patients underwent scimitar vein surgery; 11 had baffling or reimplantation and 11 only had the new operation that included resection of the atrial septum with removal of the muscular limbus. The left atrium was pulled down toward the scimitar vein and a V-shaped incision made at the scimitar vein atrial junction with the space filled with a pulmonary homograft. If the scimitar vein coursed adjacent to the atrium, a V-shaped incision was made into the scimitar vein and directly anastomosed to the atrium. A patch of autologous pericardium was used to septate the atrium and an additional patch placed anteriorly to augment the inferior vena cava.

Results

Of the 11 patients who had baffling or reimplantation, 5 developed pulmonary vein obstruction between 45 days and 9.5 months after surgery associated with baffle thrombosis or tension on the pulmonary vein. None of the 11 patients who only had the new procedure developed pulmonary vein obstruction during postoperative monitoring up to 3.6 years.

Conclusions

Patients having only the multipatch procedure for repair of scimitar syndrome have not developed postoperative pulmonary vein obstruction in the short to intermediate term.

The Fontan outcomes network: first steps towards building a lifespan registry for individuals with Fontan circulation in the United States

The Fontan Outcomes Network was created to improve outcomes for children and adults with single ventricle CHD living with Fontan circulation. The network mission is to optimise longevity and quality of life by improving physical health, neurodevelopmental outcomes, resilience, and emotional health for these individuals and their families. This manuscript describes the systematic design of this new learning health network, including the initial steps in development of a national, lifespan registry, and pilot testing of data collection forms at 10 congenital heart centres.

Fontan-associated liver disease: pathophysiology, investigations, predictors of severity and management

Cardiac hepatopathy is the liver injury resulting from congestion and ischaemia associated with acute or chronic heart failure. The improved longevity of adults with operated congenital heart disease who develop heart failure as an increasingly late event makes this form of liver injury increasingly clinically relevant. Patients with congenital heart disease with a single ventricle anomaly, who require creation of a Fontan circulation, are particularly vulnerable as they have elevated venous filling pressures with chronic liver congestion. Progression to liver fibrosis and eventually cirrhosis may occur, with its associated risks of liver failure and hepatocellular carcinoma. This risk likely increases over the patient's lifetime, related to the duration post-surgical repair and reflects the chronicity of congestion. Liver biopsy is rarely performed due to a higher risk of complications in the setting of elevated venous pressures, and the frequent use of anticoagulation. Non-invasive methods of liver assessment are poorly validated and different factors require consideration compared to other chronic liver diseases. This review discusses the current understanding of cardiac hepatopathy in congenital heart disease patients with a Fontan circulation. This entity has recently been called Fontan Associated Liver Disease in the literature, with the term useful in recognising that the pathophysiology is incompletely understood, and that long-standing venous pressure elevation and hypoxaemia are presumed to play an additional significant role in the pathogenesis of the liver injury.

Surgery for Adult Congenital Heart Disease

Technical and medical improvements for congenital cardiac disease in children have contributed to an increasing population of patients who survive into adulthood. These patients may be prone to progression of their native palliated disease or suffer from sequelae of their childhood repair that requires repeat surgical intervention. Surgery for adult congenital cardiac disease poses unique challenges and risks.

Risk of Liver Cirrhosis and Hepatocellular Carcinoma after Fontan Operation: A Need for Surveillance

Liver cirrhosis and hepatocellular carcinoma (HCC) are serious late complications that can occur after the Fontan procedure. This study aimed to investigate the cumulative incidence of cirrhosis and HCC and to identify specific features distinguishing HCC from benign arterial-phase hyperenhancing (APHE) nodules that developed after the Fontan operation. We retrospectively enrolled 313 post-Fontan patients who had been followed for more than 5 years and had undergone ultrasound or computed tomography (CT) of the liver between January 2000 and August 2018. Cirrhosis was diagnosed radiologically. The estimated cumulative incidence rates of cirrhosis at 5, 10, 20, and 30 years after the Fontan operation were 1.3%, 9.2%, 56.6%, and 97.9%, respectively. Multiphasic CT revealed that 18 patients had APHE nodules that were ≥1 cm in size and showed washout in the portal venous phase (PVP)/delayed phase, which met current noninvasive HCC diagnosis criteria. Among them, only seven patients (38.9%, 7/18) were diagnosed with HCC. After cirrhosis developed, the annual incidence of HCC was 1.04%. The appearance of washout in the PVP (p = 0.006), long time elapsed since the initial Fontan operation (p = 0.04), large nodule size (p = 0.03), and elevated serum α-fetoprotein (AFP) level (p < 0.001) were significantly associated with HCC. In conclusion, cirrhosis is a frequent late complication after Fontan operation, especially after 10 years, and HCC is not a rare complication after cirrhosis development. Diagnosis of HCC should not be based solely on the current imaging criteria, and washout on PVP and clinical features might be helpful to differentiate HCC nodules from benign APHE nodules.

The Adult Patient with a Fontan

The authors summarize the most important anatomic and physiologic substrates of Fontan circulation. Common anatomic substrates include hypoplastic left heart syndrome, tricuspid atresia, double inlet left ventricle, and unbalanced atrioventricular septal defects. After the Fontan operation exercise capacity is limited and the key hemodynamic drivers is limited preload due to a relatively fixed pulmonary vascular resistance. The authors provide contemporary data on survival, morbidity, and need for reintervention. Operative morality is now expected to be less than 1% and 30 year survival approximately 89%. The authors delineate potential therapeutic approaches for the potential late complications.

Recent outcomes of the extracardiac Fontan procedure in patients with hypoplastic left heart syndrome

Objective:

To investigate patient-related factors, echocardiographic, and anatomic variables associated with immediate and long-term clinical outcomes after extracardiac Fontan procedure at our institution.

Materials and Methods:

Retrospective review of preoperative cardiac catheterizations and echocardiograms as well as medical records of all children with hypoplastic left heart syndrome (HLHS) who underwent Fontan between June 2002 and December 2018.

Results:

Seventy-seven patients with HLHS were included (age 4 years [1.5–11.7]). Seventy patients (91%) received a nonfenestrated Fontan and 57 patients (74%) underwent Fontan without cardiopulmonary bypass (CPB). Presence of a Fontan fenestration (P = 0.69) and use of CPB (P = 0.79) did not differ between those with <2 weeks compared to those with ≥2 weeks of chest tube drainage. There were no differences in either pre- or intra-operative hemodynamics between patients who weighed <15 kg compared to those who weighed ≥15 kg at time of surgery; incidence of death, transplant, and transplant listing were similar between weight groups. Inferior vena cava (IVC) diameter z-score did not differ among patients with and without chylous chest tube drainage (P = 0.78), with and without development of protein losing enteropathy (P = 0.23), or death/heart transplant/transplant listing compared to survivors without transplant (P = 0.26).

Conclusion:

In HLHS patients undergoing Fontan, preoperative weight and IVC diameter appeared to have no influence on immediate postoperative outcomes. Performing the Fontan off CPB and with a fenestration also conferred no added clinical benefit. These observations should be considered when deciding optimal timing for Fontan completion.

Targeted metabolomic analysis of serum amino acids in the adult Fontan patient with a dominant left ventricle

Growing interest lies in the assessment of the metabolic status of patients with a univentricular circulation after Fontan operation, especially in changes of amino acid metabolism. Using targeted metabolomic examinations, we investigated amino acid metabolism in a homogeneous adult Fontan-patient group with a dominant left ventricle, seeking biomarker patterns that might permit better understanding of Fontan pathophysiology and early detection of subtle ventricular or circulatory dysfunction. We compared serum amino acid levels (42 analytes; AbsoluteIDQ p180 kit, Biocrates Life Sciences, Innsbruck, Austria) in 20 adult Fontan patients with a dominant left ventricle and those in age- and sex-matched biventricular controls. Serum concentrations of asymmetric dimethylarginine, methionine sulfoxide, glutamic acid, and trans-4-hydroxyproline and the methionine sulfoxide/methionine ratio (Met-SO/Met) were significantly higher and serum concentrations of asparagine, histidine, taurine, and threonine were significantly lower in patients than in controls. Met-SO/Met values exhibited a significant negative correlation with oxygen uptake during exercise. The alterations in amino acid metabolome that we found in Fontan patients suggest links between Fontan pathophysiology, altered cell energy metabolism, oxidative stress, and endothelial dysfunction like those found in biventricular patients with congestive heart failure. Studies of extended amino acid metabolism may allow better understanding of Fontan pathophysiology that will permit early detection of subtle ventricular or circulatory dysfunction in Fontan patients.

Pearls and Pitfalls in Pediatric Fontan Operation Imaging

The Fontan operation or the total cavopulmonary connection is a palliative surgery for single ventricle congenital heart disease where the systemic venous return circumvents a pumping chamber and flows directly into the pulmonary circuit. With surgical and medical advances, there has been improvement in life expectancy of these patients, however, it has also resulted in unique complications from the physiology that requires diligent surveillance. A critical component relies on optimal imaging for diagnosis and treatment of these complications. This article describes the normal anatomy of the Fontan circulation, current imaging modalities and techniques, and frequently encountered complications seen when imaging the patients who have undergone Fontan palliation.

Treatment strategies for protein-losing enteropathy in Fontan-palliated patients

OBJECTIVE

Protein-losing enteropathy is an infrequent but severe condition occurring after Fontan procedure. The multifactorial pathogenesis remains unclear and no single proposed treatment strategy has proven universally successful. Therefore, we sought to describe different treatment strategies and their effect on clinical outcome and mortality.

MATERIAL AND METHODS

We performed a retrospective observational study. From the total cohort of 439 Fontan patients treated in our institution during the study period 1986-2019, 30 patients (6.8%) with protein-losing enteropathy were identified. Perioperative, clinical, echocardiographic, laboratory, and invasive haemodynamic findings and treatment details were analysed.

RESULTS

Median follow-up after disease onset was 13.1 years [interquartile range 10.6]. Twenty-five patients received surgical or interventional treatment for haemodynamic restrictions. Medical treatment, predominantly pulmonary vasodilator and/or systemic anti-inflammatory therapy with budesonide, was initiated in 28 patients. In 15 patients, a stable remission could be achieved by medical or surgical procedures (n = 3 each), by combined multimodal therapy (n = 8), or ultimately by cardiac transplantation (n = 1). Phrenic palsy, bradyarrhythmia, Fontan pathway stenosis, and absence of a fenestration were significantly associated with development of protein-losing enteropathy (p = 0.001-0.48). Ten patients (33.3%) died during follow-up; 5-year survival estimate was 96.1%. In unadjusted analysis, medical therapy with budesonide and pulmonary vasodilator therapy in combination was associated with improved survival.

CONCLUSIONS

Protein-losing enteropathy is a serious condition limiting survival after the Fontan procedure. Comprehensive assessment and individual treatment strategies are mandatory to achieve best possible outcome. Nevertheless, relapse is frequent and long-term mortality substantial. Cardiac transplantation should be considered early as treatment option.

Lymphopenia in adults after the Fontan operation: prevalence and associations

Lymphopenia is common in adults who have had a Fontan operation although its aetiology and clinical implications remain unknown. Previous work suggests an association between lymphopenia and both liver disease and splenomegaly. The objective of this study was to assess the prevalence of lymphopenia in adults with a Fontan circulation and evaluate its associations with risk factors and clinical outcomes. Using a retrospective cohort study design, we studied 73 adult Fontan patients (age 25.0 ± 8.4 years) who had a complete blood count and abdominal imaging performed. Patients with protein-losing enteropathy were excluded. Clinical data were extracted from hospital records. The mean white blood cell count was 6580 ± 220/ml with a mean lymphocyte count of 1223 ± 508/ml. Lymphopenia, defined as lymphocyte count <1000/ml, was present in 23 (32%) patients. Patients with lymphopenia had a lower total white blood cell count (5556 ± 2517 versus 7136 ± 1924/ml, p = 0.009) and a lower platelet count (162 ± 69 versus 208 ± 69 k/ml, p = 0.008). Lymphopenia was also associated with findings of portal hypertension, including splenomegaly (36 versus 14%, p = 0.04), varices (22 versus 6%, p = 0.04), and ascites (39 versus 14%, p = 0.02). Lymphopenia did not correlate with any cardiac imaging, haemodynamic or exercise testing variables. In conclusion, lymphopenia is common in adult Fontan patients and is associated with markers of portal hypertension. Larger studies are needed to better define the relationship between lymphopenia and clinical outcomes.

The Year in Review: Anesthesia for Congenital Heart Disease 2019

This review focuses on the literature published from January 2019 to February 2020 that is of interest to anesthesiologists taking care of children and adults with congenital heart disease. Five themes are addressed during this time period, and 59 peer-reviewed articles are discussed.

Percutaneous coronary intervention following Fontan procedure

Fontan procedure is known to increase the risk of thromboembolic events. However, coronary artery thrombotic occlusion is rarely reported in patients with Fontan procedure. We present a case of a 10-year-old boy with hypoplastic left heart syndrome palliated with a Fontan procedure who presented with myocardial infarction secondary to thrombotic occlusion of the left circumflex coronary artery. He underwent successful percutaneous coronary intervention with thrombus aspiration, balloon angioplasty, and stent placement, highlighting the necessity of collaboration between congenital and adult cardiologists to treat acute coronary syndrome among this challenging young population.

Proceedings From the 2019 Stanford Single Ventricle Scientific Summit: Advancing Science for Single Ventricle Patients: From Discovery to Clinical Applications

Because of remarkable advances in survival over the past 40 years, the worldwide population of individuals with single ventricle heart disease living with Fontan circulation has grown to ≈70 000, with nearly half aged >18 years. Survival to at least 30 years of age is now achievable for 75% of Fontan patients. On the other hand, single ventricle patients account for the largest group of the 6000 to 8000 children hospitalized with circulation failure, with or without heart failure annually in the United States, with the highest in‐hospital mortality. Because there is little understanding of the underlying mechanisms of heart failure, arrhythmias, pulmonary and lymphatic vascular abnormalities, and other morbidities, there are no specific treatments to maintain long‐term myocardial performance or to optimize overall patient outcomes.

Providing a framework of principles for conceptualising the Fontan circulation

The Fontan operation remains the final palliation for thousands of patients with complex congenital heart disease. By creating a Fontan circuit, control of cardiac output and congestion is wrested away from the ventricle and new haemodynamic forces take control. Understanding how to control the flow in the Fontan circuit will enable clinicians to improve patient management and possibly prevent future complications.

Conclusion

This review proposes a framework of principles to conceptualise the functionality and limitations of a Fontan circulation.

Heart failure in single right ventricle congenital heart disease: physiological and molecular considerations

Because of remarkable surgical and medical advances over the past several decades, there are growing numbers of infants and children living with single ventricle congenital heart disease (SV), where there is only one functional cardiac pumping chamber. Nevertheless, cardiac dysfunction (and ultimately heart failure) is a common complication in the SV population, and pharmacological heart failure therapies have largely been ineffective in mitigating the need for heart transplantation. Given that there are several inherent risk factors for ventricular dysfunction in the setting of SV in addition to probable differences in molecular adaptations to heart failure between children and adults, it is perhaps not surprising that extrapolated adult heart failure medications have had limited benefit in children with SV heart failure. Further investigations into the molecular mechanisms involved in pediatric SV heart failure may assist with risk stratification as well as development of targeted, efficacious therapies specific to this patient population. In this review, we present a brief overview of SV anatomy and physiology, with a focus on patients with a single morphological right ventricle requiring staged surgical palliation. Additionally, we discuss outcomes in the current era, risk factors associated with the progression to heart failure, present state of knowledge regarding molecular alterations in end-stage SV heart failure, and current therapeutic interventions. Potential avenues for improving SV outcomes, including identification of biomarkers of heart failure progression, implications of personalized medicine and stem cell-derived therapies, and applications of novel models of SV disease, are proposed as future directions.

Prognostic value of von Willebrand factor in adult patients with congenital heart disease

OBJECTIVES

von Willebrand factor (vWF) has prognostic value in patients with heart failure (HF) and in those with liver disease. Liver congestion, due to right-sided HF (RHF), is one of the major clinical pathophysiologic manifestations in adults with congenital heart disease (ACHD). The present study's purpose was to clarify the prognostic value of plasma levels of vWF antigen (vWF:Ag) in ACHD.

METHODS

We measured vWF:Ag (%) in 382 consecutive patients (20 unrepaired cyanotic ACHD, 172 Fontan patients and 190 ACHD after biventricular repair) and compared the results with the clinical profiles and prognosis.

RESULTS

The plasma vWF:Ag level was 130±53 (normal range: 55%-190%), and 48 patients (13%) showed high levels of vWF:Ag (≥190%). Older age, Fontan circulation, higher central venous pressure, lower arterial oxygen saturation and lower plasma levels of albumin were independently associated with high log (vWF:Ag) (p<0.05-0.0001). During the follow-up of 2.4±1.4 years, 15 patients died. High log (vWF:Ag) predicted the all-cause mortality (HR 1.63 per 0.1, 95% CI 1.40 to 1.96, p<0.0001). Specifically, patients with high vWF:Ag (≥165%) had a substantially higher risk of all-cause mortality (HR 56.4, 95% CI 11.4 to 1020, p<0.0001), and this prognostic value was independent of plasma levels of brain-type natriuretic peptide.

CONCLUSIONS

High vWF:Ag may reflect RHF severity and related liver dysfunction with a strong prognostic value of all-cause mortality in ACHD. Thus, vWF:Ag might be an excellent biomarker for monitoring ACHD with RHF.

Health-Related Quality of Life in Children, Adolescents, and Adults With a Fontan Circulation: A Meta-Analysis

Background

People with a Fontan circulation experience a range of physical, psychosocial and neurodevelopmental challenges alongside, or caused by, their cardiac condition, with significant consequences for health‐related quality of life (HRQOL). We meta‐analyzed HRQOL outcomes reported by people with a Fontan circulation or their proxies and evaluated predictors of poorer HRQOL.

Methods and Results

Six electronic databases were searched for peer‐reviewed, English‐language articles published before March 2019. Standardized mean differences (SMD) were calculated using fixed and random‐effects models. Fifty articles reporting on 29 unique studies capturing HRQOL outcomes for 2793 people with a Fontan circulation and 1437 parent‐proxies were analyzed. HRQOL was lower in individuals with a Fontan circulation compared with healthy referents or normative samples (SMD, −0.92; 95% CI, −1.36 to −0.48; P<0.001). Lower scores were reported across all HRQOL domains, with the largest differences found for physical (SMD, −0.90; 95% CI, −1.13 to −0.67; P<0.001) and school/work functioning (SMD, −0.71; 95% CI, −0.90 to −0.52; P<0.001). Meta‐regression analyses found no significant predictors of self‐reported physical functioning, but older age at Fontan operation was associated with poorer emotional functioning (β=−0.124; P=0.004), and diagnosis of hypoplastic left heart was associated with poorer social functioning (β=−0.007; P=0.048). Sensitivity analyses showed use of the PedsQL Core Module was associated with lower HRQOL scores compared with the Short‐Form Health Survey‐36.

Conclusions

HRQOL outcomes for people with a Fontan circulation are lower than the general population. Optimal care acknowledges the lifelong impact of the Fontan circulation on HRQOL and offers targeted strategies to improve outcomes for this growing population.

The failing Fontan

Nearly 50 years back, Francis Fontan pioneered an operation for tricuspid atresia that bears his name today. The operation has since undergone numerous modifications and continues to be widely applied to an array of single ventricles. Despite restoring normal oxygen levels in the body, the operation creates a neoportal system where adequate cardiac output can be generated only at the expense of increased systemic venous congestion. This results in slow but relentless damage to the end organ systems especially the liver. Continuous surveillance of the patient to monitor this circulation, that will ultimately fail, is of paramount importance. Timely medical and cardiac catheterization and surgical intervention can extend the life span of Fontan patients. Ultimately a change of the hemodynamic circuit in the form of heart transplantation or ventricular assist device will be required to salvage the failing Fontan circuit.

Surgical outcomes in complex adult congenital heart disease: a brief review

Life expectancy of patients with congenital heart disease (CHD) continues to increase dramatically over the last few decades, primarily due to significant medical and surgical advancements in the field. Adult congenital heart disease (ACHD) patients are now living longer but continue to face morbidity and reduced long-term survival when compared to the general population. We briefly describe the growth of ACHD with a focus on surgical procedures and outcomes in the more complex lesions including Tetralogy of Fallot, Ebsteins Anomaly of the tricuspid valve, Coarctation of the Aorta, Transposition of the Great Arteries and single ventricle lesions. The advancing role of mechanical circulatory support and cardiac transplantation in ACHD patients is also highlighted. Cardiac surgery in these patients continues to improve with low surgical mortality rate and outstanding long-term outcomes and efficacy.

Routine Surveillance Catheterization is Useful in Guiding Management of Stable Fontan Patients

We developed a Fontan surveillance catheterization protocol as part of routine assessment of stable patients 10 years after Fontan completion. The surveillance catherization includes hemodynamic assessment with inhaled nitric oxide, angiography, liver biopsy, and transcatheter intervention if indicated. We aimed to describe hemodynamic and liver biopsy findings, response to pulmonary vasoreactivity testing, rates of transcatheter intervention, and changes in medical therapy following surveillance catheterization in stable Fontan patients. A single-center retrospective review of Fontan patients undergoing surveillance catheterization between November 2014 and May 2019 was performed. Liver biopsies were independently scored by two pathologists. Sixty-three patients underwent surveillance catheterization (mean age 14.6 ± 3.0 years). The mean Fontan pressure was 11.8 ± 2.1 mmHg. The mean cardiac index was 2.9 ± 0.6 L/min/m². In the 51 patients who underwent pulmonary vasoreactivity testing, there was a significant decrease in median pulmonary vascular resistance (1.8 [range 0.8-4.1] vs 1.4 [range 0.7-3.0] Wood units × m²; p < 0.001). The mean cardiac index increased (3.0 ± 0.6 vs 3.2 ± 0.7 L/min/m², p = 0.009). The Fontan pressure did not change significantly. Fifty-seven patients underwent liver biopsy, and all but one showed fibrosis. Nineteen patients (33.3%) demonstrated bridging fibrosis or cirrhosis. Twenty-five patients underwent 34 transcatheter interventions. Pulmonary artery or Fontan stent placement was performed in 19 patients. Phosphodiesterase type 5 inhibitors were initiated in nine patients following surveillance catheterization. Routine surveillance catheterization with liver biopsy in adolescent Fontan patients reveals information that can guide interventional and medical management. Further long-term follow-up and assessment are indicated to assess the benefit of these interventions.