Non-invasive biomarkers of Fontan-associated liver disease.

BACKGROUND & AIMS: Fontan-associated liver disease (FALD) has emerged as an important morbidity following surgical palliation of single ventricle congenital heart disease. In this study, non-invasive biomarkers that may be associated with severity of FALD were explored. METHODS: A retrospective cohort of paediatric patients post-Fontan who underwent liver biopsy at a high volume at a paediatric congenital heart disease centre was reviewed. RESULTS: Among 106 patients, 66% were male and 69% were Hispanic. The mean age was 14.4 ± 3.5 years, and biopsy was performed 10.8 ± 3.6 years post-Fontan. The mean BMI was 20.8 ± 5 kg/m2, with 27.4% meeting obesity criteria. Bridging fibrosis was observed in 35% of patients, and 10.4% of all patients had superimposed steatosis. Bridging fibrosis was associated with lower platelet counts (168.3 ± 58.4 vs. 203.9 ± 65.8 K/µl for congestive hepatic fibrosis score [CHFS] 0-2b, p = 0.009), higher bilirubin (1.7 ± 2.2 vs. 0.9 ± 0.7 mg/dl, p = 0.0090), higher aspartate aminotransferase-to-platelet ratio index [APRI] and fibrosis-4 [FIB-4] scores (APRI: 0.5 ± 0.3 vs. 0.4 ± 0.1, p <0.01 [AUC: 0.69] and FIB-4: 0.6 ± 0.4 vs. 0.4 ± 0.2, p <0.01 [AUC: 0.69]), and worse overall survival (median 2 years follow-up post-biopsy, p = 0.027). Regression modelling of temporal changes in platelet counts before and after biopsy correlated with fibrosis severity (p = 0.005). CONCLUSIONS: In this large, relatively homogeneous adolescent population in terms of age, ethnicity, and Fontan duration, bridging fibrosis was observed in 35% of patients within the first decade post-Fontan. Bridging fibrosis was associated with worse survival. Changes in platelet counts, even years before biopsy, and APRI/FIB-4 scores had modest discriminatory power in identifying patients with advanced fibrosis. Steatosis may represent an additional risk factor for disease progression in obese patients. Further prospective studies are necessary to develop strategies to screen for FALD in the adolescent population. LAY SUMMARY: In this study, the prevalence of Fontan-associated liver disease (FALD) in the young adult population and clinical variables that may be predictive of fibrosis severity or adverse outcomes were explored. Several lab-based, non-invasive markers of bridging fibrosis in FALD were identified, suggesting that these values may be followed as a prognostic biomarker for FALD progression in the adolescent population.

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.

Reduction in Radiation Dose in a Pediatric Cardiac Catheterization Lab Using the Philips AlluraClarity X-ray System.

The objective of this study was to compare radiation doses and imaging quality using Philips AlluraClarity (Philips Healthcare, Best, The Netherlands) X-ray system and an older generation reference system. AlluraClarity is a new generation fluoroscopy system designed to reduce radiation without compromising image quality, but reports of its use in pediatric patients are limited. Dose area products (DAP, mGy cm2) and DAP/kg were compared in patients catheterized using Allura Xper and AlluraClarity systems over a year of use for each. Randomly selected studies from each system were assessed for image quality. The 430 patients imaged with Clarity were larger than the 332 imaged with Xper (median BSA: 0.74 vs. 0.64 m2, p = 0.06), and median total fluoroscopic times (TFT) were similar (15.8 vs. 16.1 min, p = 0.37). Median DAPs were 8661 mGy cm2 (IQR: 18,300 mGy cm2) and 4523 mGy cm2 (IQR: 11,596 mGy cm2) with Xper and Clarity, respectively (p < 0.001). There was a reduction in median DAP in all procedure categories. After adjustment for BSA, TFT, and procedure type, using Clarity was associated with a 57.5% (95% CI 51.5-62.8%, p < 0.001) reduction in DAP for all procedures. Reductions did not significantly differ by weight (<10 kg, 10-40 kg, ≥ 40 kg). There was an adjusted percent reduction in DAP for each procedure category ranging from 39.0% (95% CI 25.6-50.1%, p < 0.001) for cardiac biopsies with or without coronary angiography to 67.6% (95% CI 61.2-72.8%, p < 0.001) for device occlusions. Mean overall imaging quality scores (4.3 ± 0.8 with Clarity vs. 4.4 ± 0.6 with Xper, p = 0.62) and scores based on specific quality parameters were similar in the two groups. Use of AlluraClarity substantially reduced radiation doses compared to the older generation reference system without compromising imaging quality in a pediatric cardiac catheterization lab.

Anomalous left coronary artery from the pulmonary artery discovered following total anomalous pulmonary venous return repair: a rare entity.

We describe a case of anomalous left coronary artery from the pulmonary artery in association with total anomalous pulmonary venous return. The infant was diagnosed with total anomalous pulmonary venous return at 6 weeks of age and underwent successful surgical repair. On routine follow-up, he was found to have an anomalous left coronary artery from the pulmonary artery without evidence of mitral regurgitation or left ventricular dysfunction. The presence of the left-to-right shunt and secondary elevation in pulmonary artery pressures likely masked the usual findings associated with this coronary anomaly.

Differential branch pulmonary artery growth after the Norwood procedure with right ventricle-pulmonary artery conduit versus modified Blalock-Taussig shunt in hypoplastic left heart syndrome.

OBJECTIVES: The Norwood procedure with right ventricle-pulmonary artery conduit is thought to improve postoperative hemodynamics in hypoplastic left heart syndrome, but its effects on pulmonary artery growth are unknown. This study evaluated pulmonary artery growth after the Norwood procedure in patients with a right ventricle-pulmonary artery conduit as compared with patients with a modified Blalock-Taussig shunt. METHODS: A total of 159 patients at our institution underwent the Norwood procedure between January 2000 and September 2005. Patients were divided into group A or B if they had a modified Blalock-Taussig shunt (n = 103) or a right ventricle-pulmonary artery conduit (n = 56). Angiograms from the pre-Glenn catheterizations were used to measure pulmonary artery size and assess shunt stenosis (n = 64). RESULTS: Fifty-five (53.4%) patients in group A versus 40 (71.4%) in group B underwent Glenn surgery. Group B patients often required an additional shunt (modified Blalock-Taussig) before the Glenn procedure because of hypoxemia (8/40 vs 1/55; P = .004). Branch pulmonary artery growth was better in group B patients who did not require an additional shunt (Nakata index 212 vs 169 mm(2)/m(2); P = .004) and more balanced than in group A (right pulmonary artery/left pulmonary artery ratio = 1.02 vs 1.39; P = .001) as a result of greater left pulmonary artery size (29 vs 19 mm(2); P = .001). However, group B experienced more shunt stenosis (8/32 vs 2/32; P = .001), underwent the Glenn operation earlier (192 vs 246 days; P = .03), and had central pulmonary artery hypoplasia develop more often than group A patients (25/32 vs 14/32; P = .01). CONCLUSION: The Norwood procedure with a right ventricle-pulmonary artery conduit promotes better distal left pulmonary artery growth resulting in more balanced branch pulmonary artery size, but central pulmonary artery hypoplasia occurs more often. Early right ventricle-pulmonary artery conduit stenosis also increases the need for additional shunting or early Glenn surgery.