Evaluation of dosing and safety outcomes of low-dose prophylactic warfarin in children after cardiothoracic surgery.

PURPOSE: Prophylactic warfarin with an International Normalized Ratio (INR) goal of 1.5 to 2.0 is one antithrombotic therapy utilized in children after cardiothoracic surgery (CTS); published sources suggest a dose of 0.1 mg/kg per day to achieve this goal. However, few studies have evaluated dosing in this population. The purpose of this study was to evaluate dosing and safety outcomes in children receiving warfarin after CTS. METHODS: A descriptive, retrospective review was conducted to evaluate warfarin dosing and INR outcomes in patients 18 years of age or younger who underwent CTS and received prophylactic warfarin with an INR goal of 1.5 to 2.0 from January 2014 through December 2018. The primary objective was to determine the median initial warfarin dose. Secondary objectives included identifying the percentage of documented INR values that were outside the therapeutic range, the percentage of patients with therapeutic INRs at discharge, and the 30-day readmission rate. RESULTS: Twenty-six patients were included in the review. The median initial warfarin dosage was 0.07 mg/kg/d (interquartile range [IQR], 0.05-0.10 mg/kg/d). Of the total of 177 INR values collected during the entire study period, 67 (37.9%) were therapeutic, 64 (36.2%) were subtherapeutic, and 46 (26.0%) were supratherapeutic. Eighteen patients (69.2%) had at least 1 supratherapeutic INR at any point during the study period, most frequently on days 2 through 4 of therapy. At discharge, 11 patients (42.3%) had therapeutic INRs. Four patients (15.4%) were readmitted within 30 days, with bleeding documented in 2 patients during their readmission. CONCLUSION: The majority of patients received an initial warfarin dose less than that specified in published recommendations but still had a supratherapeutic INR at least once during the study period. When initiating warfarin after CTS, a dosage of <0.1 mg/kg per day and frequent monitoring may be needed to achieve an INR goal of 1.5 to 2.0.

Thromboembolic Risk After Atriopulmonary, Lateral Tunnel, and Extracardiac Conduit Fontan Surgery.

BACKGROUND: Thromboembolic events contribute greatly to morbidity and mortality following Fontan surgery for univentricular hearts. OBJECTIVES: This study sought to evaluate the effect of type of Fontan surgery on thromboembolic risk. METHODS: A North American multicenter retrospective cohort study enrolled 522 patients with Fontan palliation consisting of an atriopulmonary connection (APC) (21.4%), lateral tunnel (LT) (41.8%), or extracardiac conduit (EC) (36.8%). Thromboembolic complications and new-onset atrial arrhythmia were reviewed and classified by a blinded adjudicating committee. Thromboembolic risk across surgical techniques was assessed by multivariable competing-risk survival regression. RESULTS: Over a median follow-up of 11.6 years, 10- and 20-year freedom from Fontan conversion, transplantation, or death was 94.7% and 78.9%, respectively. New-onset atrial arrhythmias occurred in 4.4, 1.2, and 1.0 cases per 100 person-years with APC, LT, and EC, respectively. APC was associated with a 2.82-fold higher risk of developing atrial arrhythmias (p < 0.001), with no difference between LT and EC (p = 0.95). A total of 71 thromboembolic events, 32 systemic and 39 venous, occurred in 12.8% of subjects, for an overall incidence of 1.1%/year. In multivariable analyses, EC was independently associated with a lower risk of systemic (hazard ratio [HR]: 0.20 vs. LT; 95% confidence interval [CI]: 0.04 to 0.97) and combined (HR: 0.34 vs. LT; 95% CI: 0.13 to 0.91) thromboembolic events. A lower incidence of combined thromboembolic events was also observed with antiplatelet agents (HR: 0.54; 95% CI: 0.32 to 0.92) but not anticoagulation (p = 0.53). CONCLUSIONS: The EC Fontan was independently associated with a lower thromboembolic risk after controlling for time-varying effects of atrial arrhythmias and thromboprophylaxis.

Resource Utilization for Prenatally Diagnosed Single-Ventricle Cardiac Defects: A Philadelphia Fetus-to-Fontan Cohort Study.

Background Healthcare resource utilization is substantial for single-ventricle cardiac defects ( SVCD ), with effort commencing at time of fetal diagnosis through staged surgical palliation. We sought to characterize and identify variables that influence resource utilization for SVCD from fetal diagnosis through death, completed staged palliation, or cardiac transplant. Methods and Results Patients with a prenatal diagnosis of SVCD at our institution from 2004 to 2011 were screened. Patients delivered with intent to treat who received cardiac care exclusively at our institution were included. Primary end points included the total days hospitalized and the numbers of echocardiograms and cardiac catheterizations. Subanalysis was performed on survivors of completed staged palliation on the basis of Norwood operation, dominant ventricular morphology, and additional risk factors. Of 202 patients born with intent to treat, 136 patients survived to 6 months after completed staged palliation. The median number of days hospitalized per patient-year was 25.1 days, and the median numbers of echocardiograms and catheterizations per patient-year were 7.2 and 0.7, respectively. Mortality is associated with increased resource utilization. Survivors had a cumulative length of stay of 57 days and underwent a median of 21 echocardiograms and 2 catheterizations through staged palliation. Right-ventricle-dominant lesions requiring Norwood operation are associated with increased resource utilization among survivors of staged palliation. Conclusions For fetuses with SVCD , those with dominant right-ventricular morphology requiring Norwood operation demand increased resource utilization regardless of mortality. Our findings provide insight into care for SVCD , facilitate precise prenatal counseling, and provide information about the resources utilized to successfully manage SVCD .

Pacemakers are associated with a higher risk of late death and transplantation in the Fontan population.

BACKGROUND: The need for permanent pacing has been identified as a predictor of poor outcomes in the late survivors of Fontan surgery. However, it is not clear if the need for a pacemaker is a surrogate marker of a declining Fontan state, or if pacing is deleterious to the Fontan circulation. OBJECTIVES: We sought to compare the long-term outcomes of propensity-matched Fontan patients with and without a permanent pacemaker. METHODS: Patients who have survived Fontan completion with a documented history of cardiac arrhythmia were identified from the Australia and New Zealand Fontan Registry. Pacemaker insertion details, cardiac function and electrophysiological data were obtained for the patients with a permanent pacemaker. Survival analysis was performed with propensity score matching to compare late survival and outcomes in patients with versus without a pacemaker. RESULTS: There was a total of 310 patients with a history of cardiac arrhythmia, of which 126 (41%) had a permanent pacemaker. After propensity-score matching, 99 pairs were generated (n = 198). Patients with a permanent pacemaker had a higher risk of death (HR 3.32 95% CI 1.60-6.90, p = 0.001) and death or transplantation (HR 3.55 95% CI 1.87-6.73, p < 0.001). Patients who were only paced atrially were not at a significantly increased risk of death or transplantation. However, patients who were ventricular paced >50% of the time were much more likely to encounter late death or transplantation (HR 3.82 95% CI 1.64-8.95, p = 0.002). CONCLUSIONS: Having a permanent pacemaker and needing ventricular pacing is likely associated with an increased risk of death and transplantation in patients with a Fontan circulation.

Mode of death and predictors of mortality in adult Fontan survivors: A Japanese multicenter observational study.

BACKGROUND: Mortality rates may be high in adult Fontan patients; however, the clinical determinants remain unclear. PURPOSE: We conducted a prospective multicenter study of adult Fontan survivors to determine the 5-year mortality rate and clarify the determinants. METHOD AND RESULTS: We followed 600 adult Fontan survivors from 40 Japanese institutions (307 men, 28 ±â€¯7 years old, follow-up: 18 ±â€¯6 years). The New York Heart Association (NYHA) functional class I and II was 51% and 42%, respectively. During the follow-up period of 4.1 ±â€¯1.6 years, 33 patients died, and the 5-year survival rate was 93.5%. The mode of death was heart failure in 11 patients (34%), arrhythmia or sudden death in 8 (24%), cancer in 5 (15%), perioperative problems and hemostatic problems in 4 each (12% for each), and infection in 1 (3%). Left isomerism, prior hospitalization, protein losing enteropathy (PLE), pulmonary arteriovenous fistulae, NYHA functional class, impaired hemodynamics, hyponatremia, hepatorenal dysfunction, and use of diuretics were associated with a high mortality rate (p < 0.05-0.0001). Further, PLE (hazard ratio [HR]: 14.4), left isomerism (HR: 3.5), and NYHA (HR: 2.4) independently predicted a high 5-year high mortality (p < 0.05 for all). The incidence of cancer-related mortality increased markedly with age >40 years. CONCLUSIONS: Majority of the Japanese adult Fontan survivors had good functional status, with an acceptable 5-year survival rate. However, the significant prevalence of non-cardiac mortality highlights Fontan pathophysiology as a multi-organ disease that requires a multidisciplinary management strategy to improve the long-term outcome.

The clinical spectrum of Fontan-associated liver disease: results from a prospective multimodality screening cohort.

AIMS: Liver fibrosis and cirrhosis are a consequence of a Fontan physiology, and determine prognosis. It is unclear whether non-invasive assessment of liver pathology is helpful to provide clinically relevant information. The aims of this study were to assess the spectrum of Fontan-associated liver disease (FALD) and usefulness of non-invasive methods to assess biopsy confirmed liver fibrosis. METHODS AND RESULTS: Hepatic screening of consecutive patients consisted of a blood panel, ultrasonography, elastography, contrast-enhanced magnetic resonance imaging (MRI)/computed tomography (CT) scan, and liver biopsy (scored with Fontan specific fibrosis scores and collagen proportionate area; CPA). Fibrosis parameters, varices, ascites, and splenomegaly were measured on imaging. Thirty-eight of 49 referred patients (27 ± 6.6 years, 73.7% male) underwent the complete screening protocol. Liver fibrosis on biopsy was present in all patients, and classified as severe (Stages 3-4) in 68%. Median CPA was 22.5% (16.9-29.5) and correlated with individual fibrosis scores. ELF® and liver stiffness were elevated, but MELD-XI scores were low in all patients. Fibrosis severity neither correlated to ELF® and liver stiffness, nor to (semi-) quantitative fibrosis parameters on MRI/CT. Varices were present in 50% and hyperenhancing nodules in 25% of patients, both independent of fibrosis stage, but varices were associated with higher CPA values. CONCLUSION: The FALD spectrum includes both hepatic congestion and severe fibrosis, with signs of portal hypertension and hyperenhancing nodules as significant manifestations. Routine imaging, transient elastography, and serum biomarkers are unable to accurately assess severity of liver fibrosis in this cohort. Future research should focus on validating new diagnostic tools with biopsy as the reference standard.

Hepatic and renal end-organ damage in the Fontan circulation: A report from the Australian and New Zealand Fontan Registry.

BACKGROUND: Hepatic and renal dysfunction have been observed in survivors of the Fontan procedure, however their incidence and associated factors remain poorly defined. METHODS: A total of 152 participants from a Registry of 1528 patients underwent abdominal ultrasound, transient elastography (FibroScan), serum fibrosis score (FibroTest), in vivo Tc-99m DTPA measurement of glomerular filtration rate (mGFR), and urine albumin-creatinine ratio (ACR). RESULTS: Mean age and time since Fontan were 19.8 ±â€¯9.3 and 14.1 ±â€¯7.6 years, respectively. Features suggestive of hepatic fibrosis were observed on ultrasound in 87/143 (61%) and no patient was diagnosed with hepatocellular carcinoma. FibroScan median kPa was ≥10 in 117/133 (88%), ≥15 in 75/133 (56%), and ≥20 in 41/133 (31%). Fifty-four patients (54/118, 46%) had a FibroTest score ≥0.49 (equivalent to ≥F2 fibrosis). FibroTest score correlated with FibroScan value (r = 0.24, p = 0.015) and ACR (r = 0.29, p = 0.002), and patients with ultrasound features of hepatic fibrosis had a higher FibroScan median kPa (19.5 vs 15.4, p = 0.002). Renal impairment was mild (mGFR 60-89 ml/min/1.73 m2) in 46/131 (35%) and moderate (mGFR 30-59 ml/min/1.73 m2) in 3/131 (2%). Microalbuminuria was detected in 52/139 participants (37%). By multivariable analysis, time since Fontan was associated with increased FibroScan median kPa (ß = 0.89, 95% CI 0.54-1.25, p = 0.002) and decreased mGFR (ß = -0.77, 95% CI -1.29-0.24, p = 0.005). CONCLUSIONS: In the second decade after Fontan hepatic and renal structure and function are abnormal in a significant number of patients: close to 60% have ultrasonographic evidence of structural hepatic abnormalities, 46% have elevated serum hepatic fibrosis scores, and 57% have either reduced glomerular filtration rate or microalbuminuria. Hepatic and renal function should be monitored for potential impacts on outcomes after Fontan completion.

Blunted peripheral blood supply and underdeveloped skeletal muscle in Fontan patients: The impact on functional capacity.

BACKGROUND: Changes in circulatory physiology are common in Fontan patients due to suboptimal cardiac output, which may reduce the peripheral blood flow and impair the skeletal muscle. The objective of this study was to investigate the forearm blood flow (FBF), cross-sectional area (CSA) of the thigh and functional capacity in asymptomatic clinically stable patients undergoing Fontan surgery. METHODS: Thirty Fontan patients and 27 healthy subjects underwent venous occlusion plethysmography, magnetic resonance imaging of the thigh musculature and maximal cardiopulmonary exercise testing. Muscle sympathetic nerve activity (MSNA), norepinephrine measures, cardiovascular magnetic resonance, handgrip strength and 6-minute walk test were also performed. RESULTS: Fontan patients have blunted FBF (1.59 ±â€¯0.33 vs 2.17 ±â€¯0.52 mL/min/100 mL p < 0.001) and forearm vascular conductance (FVC) (1.69 ±â€¯0.04 vs 2.34 ±â€¯0.62 units p < 0.001), reduced CSA of the thigh (81.2 ±â€¯18.6 vs 116.3 ±â€¯26.4 cm2p < 0.001), lower peak VO2 (29.3 ±â€¯6 vs 41.5 ±â€¯9 mL/kg/min p < 0.001), walked distance (607 ±â€¯60 vs 701 ±â€¯58 m p < 0.001) and handgrip strength (21 ±â€¯9 vs 30 ±â€¯8 kgf p < 0.001). The MSNA (30 ±â€¯4 vs 22 ±â€¯3 bursts/min p < 0.001) and norepinephrine concentration [265 (236-344) vs 222 (147-262) pg/mL p = 0.006] were also higher in Fontan patients. Multivariate linear regression showed FVC (ß = 0.653; CI = 0.102-1.205; p = 0.022) and stroke volume (ß = 0.018; CI = 0.007-0.029; p = 0.002) to be independently associated with reduced CSA of the thigh adjusted for body mass index. The CSA of the thigh adjusted for body mass index (ß = 5.283; CI = 2.254-8.312; p = 0.001) was independently associated with reduced peak VO2. CONCLUSION: Patients with Fontan operation have underdeveloped skeletal muscle with reduced strength that is associated with suboptimal peripheral blood supply and diminished exercise capacity.

Early mortality and concomitant procedures related to Fontan conversion: Quantitative analysis.

BACKGROUND: The Fontan palliation is associated with numerous complications during long-term. The Fontan conversion operation has been advocated as an option to avoid some of these problems by converting classical Fontan types to modern forms of the circulation. Early mortality of Fontan conversion, however, remains unclear as available reports include limited numbers of patients and the results are heterogeneous. METHODS: We reviewed all original articles from 1994 to 2016 reporting Fontan conversion operations. Reports were analysed with specific reference to patient demographics, patient number, concomitant arrhythmia surgery, pacemaker implantation and early mortality. RESULTS: Overall, 37 Fontan conversion studies with a total of 1182 patients were analysed, including 35 single-centre studies and 2 registers. In the 35 single-centre studies the average age at the time of conversion was 21.6years (range 10.2-30.9years). Concomitant arrhythmia operation was performed in 71.6% of patients and concomitant pacemaker implantation procedure was performed in 59.3% of patients. Early mortality varied greatly between publications ranging from 0 to 21%. Based on a random and a fixed effect model mean mortality was 5.3% and 6.2%, respectively. Lower mortality was observed in series including younger patients at the time of conversion (average age<20years, 4.6%) and in the highest volume centre (1.4%). CONCLUSION: Fontan conversion carries a substantial mortality risk. However, results vary between centres. Overall, the combination with arrhythmia surgery seems to be associated with lower early mortality especially when patients are referred at an earlier age and are treated at highly experienced centres.

Management of 1-Lung Ventilation in a Patient With Failing Fontan Circulation.

The number of patients reaching adulthood after undergoing Fontan palliation for the repair of a congenital heart defect continues to increase. In this case report, we present the anesthetic management of a patient with a history of tricuspid atresia treated with palliative Fontan repair who had developed clinical evidence of Fontan failure. He presented with septic shock secondary to streptococcal toxic shock syndrome complicated by a loculated pleural effusion. He underwent open thoracic decortication under 1-lung ventilation. Discussion focuses on the management of volume status and pulmonary vascular resistance as well as surgical implications of Fontan physiology in thoracic surgery.

Trends in Fontan surgery and risk factors for early adverse outcomes after Fontan surgery: the Australia and New Zealand Fontan Registry experience.

OBJECTIVES: This study examined changes in practice and analyzed risk factors for adverse early outcomes after Fontan surgery through use of a binational, population-based registry. METHODS: Demographic, preoperative, and perioperative data were collected from all participating institutions of the Australia and New Zealand Fontan Registry. Patient and operative characteristics were analyzed with multivariable logistic regression for impact on early mortality, early Fontan failure (death, takedown, or mechanical support), effusions (prolonging hospital stay >30 days or requiring surgical reintervention), and stay longer than 30 days. RESULTS: Overall mortality was 3.5% (37/1071) and declined throughout the study period, from 8% (1975-1990) to 4% (1991-2000) and 1% (2001-2010). There were no differences between the extracardiac and lateral tunnel modifications for any outcome. After 2006, the extracardiac conduit was performed exclusively, with 1.3% mortality. The proportion of patients with hypoplastic left heart syndrome rose to 17% in the current era, and this group had more effusions (odds ratio, 3.0; 95% confidence interval, 1.4-6.6) and stayed on average 2 days longer in the hospital. Hypoplastic left heart syndrome was also an independent risk factor for composite adverse early outcome (death, failure, prolonged effusions, or prolonged stay >30 days; odds ratio, 2.6; 95% confidence interval 1.4-4.8 respectively). CONCLUSIONS: The extracardiac conduit is now the exclusive Fontan modification performed in Australia and New Zealand. Even with a higher proportion of high-risk cases, perioperative outcomes are excellent in the modern era. Hypoplastic left heart syndrome confers a higher risk of prolonged pleural effusion and early composite adverse outcome.

Effect of aspirin and warfarin therapy on thromboembolic events in patients with univentricular hearts and Fontan palliation.

BACKGROUND: Patients with univentricular hearts and Fontan palliation are at risk for thromboembolic complications. While aspirin and warfarin therapies are currently the mainstay of prophylaxis, controversy exists as to the optimal prevention strategy. METHODS: A cohort study was conducted on the New England registry of patients born in 1985 or earlier with Fontan surgery at Boston Children's Hospital, in order to assess and compare the effect of prophylactic aspirin and warfarin on incident thromboembolic events. RESULTS: A total of 210 qualifying patients (49% male) underwent Fontan surgery at a median age of 8.5 years: 48.6% had a right atrium to pulmonary artery anastomosis, 11% a right atrium to right ventricle conduit, 38.6% a lateral tunnel, and 1.9% an extracardiac conduit. No thromboembolic prophylaxis was prescribed to 50.0%, whereas 24.3% received aspirin, and 25.7% warfarin. In multivariate analyses, lack of aspirin or warfarin was associated with a significantly higher thromboembolic event rate when compared to therapy with either [hazard ratio 8.5, 95% confidence interval (3.6-19.9), P < 0.001], with no difference between the two treatment strategies (P = 0.768). Twenty-year freedom from thromboemboli was 86% versus 52% in patients with and without thromboprophylaxis, respectively. Other factors independently associated with thromboemboli were a low post-operative cardiac index [hazard ratio 2.6, 95% confidence interval (1.2, 5.9)] and atrial fibrillation or flutter [hazard ratio 3.1, 95% confidence interval (1.2, 8.0)]. CONCLUSIONS: Prophylaxis with either aspirin or warfarin was associated with a significantly lower rate of incident thromboembolic events following Fontan palliation, with no difference between the two therapies.

Univentricular hearts in Denmark 1977 to 2009: incidence and survival.

BACKGROUND: The incidence of children born with functional univentricular heart (UVH) and their prognosis presumably changed substantially in recent years. This is due to introduction of fetal echocardiography and potential termination of pregnancy (TOP) when UVH is diagnosed (UVH TOP), and to improvements in treatment. We aimed to explore changes in incidence, to estimate changes in survival, and to describe predictors of mortality in UVH patients. METHODS: Using a population-based design we identified all UVH cases in Denmark from 1977 to 2009. RESULTS: 703 UVH live births and 106 UVH TOP were identified. A dramatic decrease in birth incidence of UVH patients and a corresponding increase in UVH TOP was observed in recent years. Mean incidence rate of UVH (live births and UVH TOP) was 0.39 per 1000 births. In adjusted analysis survival improved significantly from birth era 1977-1989 to 1990-1999 (HR 2.65, 95% confidence interval (CI), 2.06-3.42) but not significantly from 1990-1999 to 2000-2009 (HR 0.77, 95% CI, 0.57-1.05). In the birth era 2000-2009, the lowest five-year survival was seen with hypoplastic left heart syndrome (HLHS) (18.8%), whereas the best survival was seen with tricuspid atresia (79.8%). Adjusted risk of death was 7.3 times higher in the HLHS group compared to the tricuspid atresia group (95% CI, 3.94-13.47). CONCLUSIONS: This study demonstrates a dramatic decrease in birth incidence of UVH patients most probably due to a corresponding increase in UVH TOP. Despite survival improved after introduction of Fontan surgery, survival has not improved significantly during the last 20years.

Comprehensive evaluation of right ventricular function in children with different anatomical subtypes of hypoplastic left heart syndrome after Fontan surgery.

BACKGROUND: There is some evidence that hypoplastic left heart syndrome (HLHS) survivors with a larger left ventricular (LV) cavity may have poorer long-term outcome than those with mitral and aortic valve atresia (MA/AA) and negligible LV. A negative impact of the LV remnant on right ventricular (RV) function may contribute to this. METHODS: We retrospectively evaluated RV function echocardiographically using 2D, Doppler and colour tissue Doppler techniques in 42 children with HLHS after Fontan surgery. Patients diagnosed with MA/AA at birth (group 1, n = 20) were compared to all the remaining anatomical subgroups of HLHS (group 2, n = 22). RESULTS: The MA/AA group had a smaller diameter of the ascending aorta at birth (p<0.0001), smaller LV area (p<0.0001) and larger RV area at end-diastole (p = 0.004) and end-systole (p = 0.01) after Fontan. All parameters of RV function including the myocardial performance index, tricuspid annular plane systolic excursion, RV fractional area change and all regional colour Doppler derived myocardial velocities were not different between groups. CONCLUSION: In our cohort, RV function in HLHS after Fontan surgery was not different for the subgroup with MA/AA when compared to the remaining subgroups.

Late reoperations for Fontan patients: state of the art invited review.

Conversion of the atriopulmonary Fontan to a total cavopulmonary extracardiac connection with concomitant arrhythmia surgery and pacemaker placement is a safe and efficacious procedure for this patient population. From 1994 to 2007 a total of 118 patients have undergone this procedure with one (0.8%) early and nine (7.6%) late deaths. During the course of our experience with Fontan conversion our surgical strategy has evolved to include various ablative techniques to treat macro re-entrant atrial tachycardia, focal (automatic) atrial tachycardia, atrioventricular nodal reentry tachycardia, atrial tachycardia due to accessory connections, atrial fibrillation, and ventricular tachycardia. The various mechanisms that we use to treat the underlying atrial arrhythmias are described in this review. We have also encountered patients with variations of the Fontan and other complex anatomic and pathophysiologic aberrations who were not amenable to standard takedown and ablative procedures. We describe those circumstances and the solutions we found to treat those patients.

Design of a large cross-sectional study to facilitate future clinical trials in children with the Fontan palliation.

BACKGROUND: Clinical trials in children with congenital heart disease are often limited by the absence of the following: (1) a primary outcome that can be observed in a reasonable period; (2) information regarding health-related quality of life; (3) knowledge of the correlation between health status and ventricular function and exercise performance; (4) a sufficient number of children at a single institution to provide adequate statistical power; and (5) procedural and management differences between and within institutions. METHODS: The NHLBI-funded Pediatric Heart Network designed a cross-sectional study of children aged 6 to 18 years, from 7 pediatric clinical centers, who had undergone a Fontan procedure as treatment for congenital heart disease. Health-related quality of life was measured by the Child Health Questionnaire and the Congenital Heart Adolescent and Teenager Questionnaire. Ventricular function was assessed by maximal exercise testing, echocardiography, cardiac magnetic resonance imaging, and B-type natriuretic peptide. The study was designed to detect a correlation of R > or = 0.30 between health status scores and measures of ventricular function and performance in a subcohort with all study measures completed. RESULTS: A total of 1078 children were screened by chart review; 644 (60%) were eligible. The consent rate was 85% and 546 children were enrolled. Acquisition of echocardiograms, B-type natriuretic peptide, and health status was > or = 94%; completion rates were lower for maximal exercise testing (76%) and cardiac magnetic resonance imaging (41%). CONCLUSIONS: This large study provides unique information regarding the relationship between health status and clinical measures in post-Fontan patients that will facilitate the design of future randomized trials.