N-terminal pro-brain natriuretic peptide serum levels reflect attrition of the Fontan circulation

Altered Serum Proteins Suggest Inflammation, Fibrogenesis and Angiogenesis in Adult Patients with a Fontan Circulation

Previous omics research in patients with complex congenital heart disease and single-ventricle circulation (irrespective of the stage of palliative repair) revealed alterations in cardiac and systemic metabolism, inter alia abnormalities in energy metabolism, and inflammation, oxidative stress or endothelial dysfunction. We employed an affinity-proteomics approach focused on cell surface markers, cytokines, and chemokines in the serum of 20 adult Fontan patients with a good functioning systemic left ventricle, and we 20 matched controls to reveal any specific processes on a cellular level. Analysis of 349 proteins revealed 4 altered protein levels related to chronic inflammation, with elevated levels of syndecan-1 and glycophorin-A, as well as decreased levels of leukemia inhibitory factor and nerve growth factor-ß in Fontan patients compared to controls. All in all, this means that Fontan circulation carries specific physiological and metabolic instabilities, including chronic inflammation, oxidative stress imbalance, and consequently, possible damage to cell structure and alterations in translational pathways. A combination of proteomics-based biomarkers and the traditional biomarkers (uric acid, γGT, and cholesterol) performed best in classification (patient vs. control). A metabolism- and signaling-based approach may be helpful for a better understanding of Fontan (patho-)physiology. Syndecan-1, glycophorin-A, leukemia inhibitory factor, and nerve growth factor-ß, especially in combination with uric acid, γGT, and cholesterol, might be interesting candidate parameters to complement traditional diagnostic imaging tools and the determination of traditional biomarkers, yielding a better understanding of the development of comorbidities in Fontan patients, and they may play a future role in the identification of targets to mitigate inflammation and comorbidities in Fontan patients.

CA125: a new biomarker in patients with Fontan circulation

INTRODUCTION AND OBJECTIVES

Patients with Fontan circulation (FC) have a high incidence of clinical complications. However, no biomarker is able to accurately stratify risk. The aim of this study was to analyze the relationship between biomarkers and clinical complications, including carbohydrate antigen 125 (CA125) for the first time, and to propose a risk estimation based on a combination of biomarkers.

METHODS

Cross-sectional study of patients with FC. The clinical endpoint was the combination of heart failure, atrial arrhythmias, veno-venous fistulae, protein-losing enteropathy, or plastic bronchitis. Demographic, clinical, and laboratory variables were analyzed, including CA125, NT-proBNP, renal and liver function, and red cell distribution width (RDW). We performed univariate and multivariate analyses of the relationship between these variables and the composite endpoint. Cutoff values were calculated by ROC curves.

RESULTS

We included 56 patients (27.4±7.8 years). A total of 34% showed the composite endpoint, with significantly higher CA125 levels (30.1 IU/mL vs 12.6 IU/mL; P=.001). In the multivariate model, the biomarkers related to the endpoint were LnCA125 (OR, 5.1; 95%CI, 1.2-22), RDW (OR, 1.8; 95%CI, 1.1-3.1), and FIB4 (OR, 38, 95%CI, 1.7-855). The cutoff points were CA125 ≥ 20 U/mL, FIB4 ≥ 0.75, and RDW ≥ 14.5%, and the probability of the occurrence of the endpoint was 81% if ≥ 2 biomarkers were elevated.

CONCLUSIONS

CA125 elevation is associated with a higher prevalence of complications in patients with Fontan-type circulation. CA125 levels ≥ 20U/mL, FIB4 ≥ 0.75 and RDW ≥ 14.5% identify with a high probability the clinical failure of FC.

Noninvasive surrogates are poor predictors of liver fibrosis in patients with Fontan circulation

OBJECTIVES

Patients with Fontan circulation exhibit a high incidence of liver fibrosis and cirrhosis. Transient elastography (TE) and the enhanced liver fibrosis (ELF) test have proven useful as noninvasive surrogate markers of liver fibrosis for other chronic liver diseases. We evaluated whether TE and the ELF score can predict the degree of liver fibrosis in patients with Fontan circulation.

METHODS

We retrospectively reviewed the medical records of 45 adult patients with at least 10 years of Fontan duration who had undergone liver biopsy and investigated the relation between the fibrosis stage and TE and the ELF test results. Additionally, the association of these variables and other biochemical and hemodynamic parameters was assessed.

RESULTS

The mean age was 25.9 years and the mean Fontan duration was 20.8 years. Advanced liver fibrosis was present in 36 (80.0%) patients. TE or ELF score are comparable for patients with and without advanced liver fibrosis (mean 23.3 vs 24.8 kPa [P = .85] for TE; mean 8.94 vs 9.25 [P = .44] for the ELF score). However, N-terminal pro-brain natriuretic peptide level and ventricular end-diastolic pressure were higher in patients with advanced liver fibrosis (mean 224 vs 80 pg/mL [P < .01]; and mean 12 vs 9 mm Hg [P = .04], respectively). No independent predictor of advanced liver fibrosis was found in multivariate analysis.

CONCLUSIONS

TE and the ELF score were unable to predict the degree of liver fibrosis in Fontan patients. Liver biopsy remains as the only valid method to assess fibrotic burden in this population.

The Combination Clinical Value of Plasma Brain Natriuretic Peptide and Serum HbAlc in the Diagnosis of Chronic Pulmonary Heart Disease

Objective. To analyze the combination clinical value of plasma brain natriuretic peptide and serum glycated hemoglobin (HbAlc) in chronic pulmonary heart disease. Methods. A total of 200 patients with chronic pulmonary heart disease admitted to our hospital from January 2021 to January 2022 were selected as the observation group, and 200 healthy subjects were selected as the control group during the same period. All subjects were examined by an ECG vector map and plasma BNP, and HbAlc levels were detected to analyze the value and clinical significance of each index in single diagnosis and combined diagnosis. Results. Plasma BNP and HbAlc levels in the observation group were significantly higher than those in the control group ( $P<0.05$ ). There were 154 BNP positive, 146 HbAlc positive, 164 parallel combined diagnosis positive, and 132 serial combined diagnosis positive. Sensitivity of series combination diagnosis was significantly higher than other indexes ( $P<0.05$ ); especially, parallel combination diagnosis was significantly higher than other indexes ( $P<0.05$ ). Besides, area under the ROC curve of parallel combination diagnosis and series combination diagnosis was significantly higher than that of each index alone diagnosis ( $P<0.05$ ). Conclusion. In the diagnosis of chronic pulmonary heart disease, the combination of plasma BNP and HbAlc can effectively improve the diagnostic specificity and sensitivity, as well as improve the area under the ROC curve.

A Multimodal Score Accurately Classifies Fontan Failure and Late Mortality in Adult Fontan Patients

Objectives

Despite the outstanding success of the Fontan operation, it is a palliative procedure and a substantial number of patients experience late failure of the Fontan circulation. Clinical presentation and hemodynamic phenotypes of Fontan failure are considerably variable. While various parameters have been identified as risk factors for late Fontan failure, a feasible score to classify Fontan failure and possibly allow timely risk stratification is lacking. Here, we explored the possibility of developing a score based on hemodynamic, clinical and laboratory parameters to classify Fontan failure and mortality.

Methods

We performed a retrospective study in our cohort of adult Fontan patients from two institutions [n = 198, median follow-up after Fontan 20.3 (IQR 15.6–24.3) years], identifying those patients with clinical Fontan failure (n = 52, 26.3%). Various hemodynamic, echocardiographic, laboratory and clinical data were recorded and differences between patients with and without Fontan failure were analyzed. We composed a Fontan Failure Score containing 15 parameters associated with Fontan failure and/or mortality and assessed its accuracy to discriminate between patients with and without late Fontan failure as well as late mortality and survival.

Results

Late failure occurred at a median of 18.2 (IQR 9.1–21.1) years after Fontan completion. Mortality associated with Fontan failure was substantial (25/52, 48.1%) with freedom of death/transplantation/take-down of 64% at 5 years and 36% at 10 years after onset of Fontan failure, respectively. Patients with Fontan failure had a significantly higher median Fontan Failure Score compared to non-failing Fontan patients [8 points (IQR 5–10) vs. 2 points (IQR 1-5), p < 0.001]. The score accurately classifies Fontan failure as well as mortality as assessed with receiver operating characteristic analysis. Area under the curve of the Fontan Failure Score was 0.963 (95% CI 0.921; 0.985, p < 0.001) to discriminate failure and 0.916 (95% CI 0.873; 0.959, p < 0.001) to classify mortality.

Conclusion

We have developed an uncomplex yet remarkably accurate score to classify Fontan failure and late mortality in adult Fontan patients. Prospective validation and most likely refinement and calibration of the score in larger and preferably multi-institutional cohorts is required to assess its potential to predict the risk of Fontan failure and late mortality.