Accuracy of elastography versus biopsy in assessing severity of liver fibrosis in young Fontan patients.

OBJECTIVES: We performed a single-centre retrospective study comparing the accuracy of non-invasive elastography with liver biopsy in accurate assessment of Fontan-associated liver disease. METHODS: Fontan patients who underwent combined assessment with a percutaneous liver biopsy and non-invasive elastography between January 2015 and December 2023 at our Children's hospital were included. Liver biopsies were classified using the Congestive Hepatic Fibrosis Score as early Fontan-associated liver disease (scores 1, 2) and advanced Fontan-associated liver disease (score 3/bridging fibrosis and score 4/cirrhosis). Elastography values were categorised as advanced Fontan-associated liver disease for liver elasticity >2.1 m/s by ultrasound and liver stiffness >5 KPa on magnetic resonance elastography. RESULTS: We included 130 patients (116 children, 89%, mean age at biopsy: 14.6 years ± 3.6) who underwent liver biopsy at a mean duration of 11.1 years (±0.3) following Fontan surgery. Advanced Fontan-associated liver disease was noted in 41 (31.5%) patients with 13 (10%) showing frank cirrhosis. Pre-biopsy ultrasound showed advanced liver fibrosis in 18/125 (14%), with low sensitivity (23%), high specificity (90%), and low accuracy (68%, k = 0.1) in diagnosing advanced Fontan-associated liver disease. Similarly, pre-biopsy magnetic resonance elastography showed advanced fibrosis in 23/86 (27%) of patients, with low sensitivity (30%), fair specificity (75%), and low accuracy (63%, k = 0.1). Interestingly, advanced Fontan-associated liver disease was missed by ultrasound in 29% and by magnetic resonance elastography in 25% of patients. Advanced Fontan-associated liver disease was associated with lower platelet count (p = 0.02) and higher Gamma-glutamyl Transferase levels (p = 0.02). CONCLUSION: Advanced hepatic fibrosis is common among paediatric Fontan patients. Non-invasive elastography may overestimate and underestimate the degree of liver fibrosis, and therefore, liver biopsy may be required for confirming disease severity.

Safety and utility of CardioMEMS device for remote pulmonary artery monitoring in paediatric Fontan patients: a case series.

Background: Patients with single ventricle congenital heart disease who undergo total cavo-pulmonary anastomosis (Fontan surgery) suffer from elevated pulmonary artery pressure (PAP), which leads to multiple adverse sequelae. Traditionally, the Fontan pressures are assessed via invasive haemodynamic catheterization that exposes these medically fragile patients to the risks of vascular injury and anaesthesia. While the CardioMEM remote PAP monitor has been extensively used in adults with heart failure, the safety of this device has not been established in children. Case summary: We report safety and utility of this device in eight paediatric Fontan patients. Our patients ranged from 9 to 18 years of age. There were no reported complications related to the implantation of the CardioMEMS device in our population. Discussion: This is the first case series of safety of CardioMEMS device in paediatric Fontan Powered by Editorial Manager® and ProduXion Manager® from Aries Systems Corporation patients. Our experience indicates that the device may be safely utilized for the management of Fontan-related complications in this vulnerable population.

Elevated Aortic Augmentation Index in Children Following Fontan Palliation: Evidence of Stiffer Arteries?

Children born with a functional single ventricle who undergo Fontan palliation are prone to early pump failure. Whether they develop early arterial stiffness with resultant increase in afterload is not well known. We hypothesized that the aortic stiffness is higher in pediatric Fontan patients when compared to healthy controls. A prospective study was conducted at the Children's Hospital of Michigan. Twenty-two Fontan patients (aged 6-21 years) were compared with 22 healthy controls (aged 9-17 years) selected from children referred to our clinic who had normal cardiac anatomy and function on the echocardiogram. Aortic stiffness was assessed noninvasively by measuring the aortic augmentation index (AAI) using applanation tonometry (Sphygmocor, Atcor, IL). AAI was calculated as AP/PP where augmentation pressure (AP) is the increase in aortic systolic blood pressure (BP) and pulse pressure (PP) is the difference between aortic systolic and diastolic BP. Ten patients (45 %) had hypoplastic left ventricle, and 11 (50 %) had undergone aortic arch surgery. The median AAI was significantly higher in Fontan patients when compared to controls (12.5, IQR 4.8, 17.3 vs 0, IQR -6.3, 5.8; p = 0.0003). History of aortic arch surgery and single ventricle morphology did not have a significant impact on AAI. Pediatric patients who undergo Fontan palliation have significantly higher AAI, a marker of aortic stiffness and increased afterload, compared to healthy controls. Larger longitudinal studies are warranted to elucidate the possible contribution of elevated AAI on pump failure in these patients.

A case of life-threatening Staphylococcus aureus endocarditis involving percutaneous transcatheter prosthetic pulmonary valve.

While right ventricle to pulmonary artery homograft is the surgical procedure of choice for relieving right ventricle outflow tract obstruction; it is limited by the need for multiple surgical replacements owing to progressive conduit obstruction, valve dysfunction, or patient growth. Since January 2010, percutaneous transcatheter placement of prosthetic pulmonary valve (Melody valve) has emerged as an attractive alternative to surgical replacement of dysfunctional right ventricle to pulmonary artery homograft in the United States. We report a case of 19-year-old girl born with truncus arteriosus who underwent transcatheter placement of prosthetic pulmonary valve due to homograft insufficiency. She presented after 4 months with a febrile episode and was found to have Staphylococcus aureus endocarditis of her prosthetic valve. The infection caused multi-organ dysfunction despite bacteriological clearance and led to severe dysfunction of the valve which ultimately required surgical removal. The case highlights a rare but serious complication of percutaneous prosthetic pulmonary valves.