State of the art of the Fontan strategy for treatment of univentricular heart disease [version 1; referees: 2 approved]

In patients with a functionally univentricular heart, the Fontan strategy achieves separation of the systemic and pulmonary circulation and reduction of ventricular volume overload. Contemporary modifications of surgical techniques have significantly improved survival. However, the resulting Fontan physiology is associated with high morbidity. In this review, we discuss the state of the art of the Fontan strategy by assessing survival and risk factors for mortality. Complications of the Fontan circulation, such as cardiac arrhythmia, thromboembolism, and protein-losing enteropathy, are discussed. Common surgical and catheter-based interventions following Fontan completion are outlined. We describe functional status measurements such as quality of life and developmental outcomes in the contemporary Fontan patient. The current role of drug therapy in the Fontan patient is explored. Furthermore, we assess the current use and outcomes of mechanical circulatory support in the Fontan circulation and novel surgical innovations. Despite large improvements in outcomes for contemporary Fontan patients, a large burden of disease exists in this patient population. Continued efforts to improve outcomes are warranted. Several remaining challenges in the Fontan field are outlined

Multivendor Evaluation of Automated MRI Postprocessing of Biventricular Size and Function for Children With and Without Congenital Heart Defects

BACKGROUND Manually segmenting cardiac structures is time-consuming and produces variability in MRI assessments. Automated segmentation could solve this. However, current software is developed for adults without congenital heart defects (CHD). PURPOSE To evaluate automated segmentation of left ventricle (LV) and right ventricle (RV) for pediatric MRI studies. STUDY TYPE Retrospective comparative study. POPULATION Twenty children per group of: healthy children, LV-CHD, tetralogy of Fallot (ToF), and univentricular CHD, aged 11.7 [8.9-16.0], 14.2 [10.6-15.7], 14.6 [11.6-16.4], and 12.2 [10.2-14.9] years, respectively. SEQUENCE/FIELD STRENGTH Balanced steady-state free precession at 1.5 T. ASSESSMENT Biventricular volumes and masses were calculated from a short-axis stack of images, which were segmented manually and using two fully automated software suites (Medis Suite 3.2, Medis, Leiden, the Netherlands and SuiteHeart 5.0, Neosoft LLC, Pewaukee, USA). Fully automated segmentations were manually adjusted to provide two further sets of segmentations. Fully automated and adjusted automated segmentation were compared to manual segmentation. Segmentation times and reproducibility for each method were assessed. STATISTICAL TESTS Bland Altman analysis and intraclass correlation coefficients (ICC) were used to compare volumes and masses between methods. Postprocessing times were compared by paired t-tests. RESULTS Fully automated methods provided good segmentation (ICC > 0.90 compared to manual segmentation) for the LV in the healthy and left-sided CHD groups (eg LV-EDV difference for healthy children 1.4 ± 11.5 mL, ICC: 0.97, for Medis and 3.0 ± 12.2 mL, ICC: 0.96 for SuiteHeart). Both automated methods gave larger errors (ICC: 0.62-0.94) for the RV in these populations, and for all structures in the ToF and univentricular CHD groups. Adjusted automated segmentation agreed well with manual segmentation (ICC: 0.71-1.00), improved reproducibility and reduced segmentation time in all patient groups, compared to manual segmentation. DATA CONCLUSION Fully automated segmentation eliminates observer variability but may produce large errors compared to manual segmentation. Manual adjustments reduce these errors, improve reproducibility, and reduce postprocessing times compared to manual segmentation. Adjusted automated segmentation is reasonable in children with and without CHD. EVIDENCE LEVEL 3. TECHNICAL EFFICACY Stage 2

Functional Echocardiographic and Serum Biomarker Changes Following Surgical and Percutaneous Atrial Septal Defect Closure in Children

BACKGROUND: Ventricular performance is temporarily reduced following surgical atrial septa! defect closure. Cardiopulmonary bypass and changes in loading conditions are considered important factors, but this phenomenon is incompletely understood. We aim to characterize biventricular performance following surgical and percutaneous atrial septal defect closure and to relate biomarkers to ventricular performance following intervention. METHODS AND RESULTS: In this multicenter prospective study, children scheduled for surgical or percutaneous atrial septal defect closure were included. Subjects were assessed preoperatively, in the second week postintervention (at 2-weeks follow-up), and 1-year postintervention (1-year follow-up). At each time point, an echocardiographic study and a panel of biomarkers were obtained. Sixty-three patients (median age, 4.1 [interquartile range, 3.1-6.1] years) were included. Forty-three patients underwent surgery. At 2-weeks follow-up, right ventricular global longitudinal strain was decreased for the surgical, but not the percutaneous, group (-17.6 +/- 4.1 versus -27.1 +/- 3.4; P CONCLUSIONS: Right, and to a lesser degree left, ventricular performance was reduced early after surgical atrial septal defect closure. Right ventricular performance at 1-year follow-up remained below baseline levels. Several biomarkers showed a pattern over time similar to ventricular performance. These biomarkers may provide insight into the processes that affect ventricular function

Functional Echocardiographic and Serum Biomarker Changes Following Surgical and Percutaneous Atrial Septal Defect Closure in Children

BACKGROUND: Ventricular performance is temporarily reduced following surgical atrial septal defect closure. Cardiopulmonary bypass and changes in loading conditions are considered important factors, but this phenomenon is incompletely under-stood. We aim to characterize biventricular performance following surgical and percutaneous atrial septal defect closure and to relate biomarkers to ventricular performance following intervention. METHODS AND RESULTS: In this multicenter prospective study, children scheduled for surgical or percutaneous atrial septal defect closure were included. Subjects were assessed preoperatively, in the second week postintervention (at 2-weeks follow-up), and 1-year postintervention (1-year follow-up). At each time point, an echocardiographic study and a panel of biomarkers were obtained. Sixty-three patients (median age, 4.1 [interquartile range, 3.1– 6.1] years) were included. Forty-three patients underwent surgery. At 2-weeks follow-up, right ventricular global longitudinal strain was decreased for the surgical, but not the percutaneous, group (−17.6±4.1 versus −27.1±3.4; P<0.001). A smaller decrease was noted for left ventricular global longitudinal strain at 2-weeks follow-up for the surgical group (surgical versus percutaneous, −18.6±3.2 versus −20.2±2.4; P=0.040). At 1-year follow-up, left ventricular performance returned to baseline, whereas right ventricular performance improved, but did not reach preintervention levels. Eight biomarkers relating to cardiovascular and immunological processes differed across study time points. Of these biomarkers, only NT-proBNP (N-terminal pro-B-type natriuretic peptide) correlated with less fa-vorable left ventricular global longitudinal strain at 2-weeks follow-up. CONCLUSIONS: Right, and to a lesser degree left, ventricular performance was reduced early after surgical atrial septal defect closure. Right ventricular performance at 1-year follow-up remained below baseline levels. Several biomarkers showed a pattern over time similar to ventricular performance. These biomarkers may provide insight into the processes that affect ventricular function