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Venous Measurements as Predictors of Long-Term Fontan Complications: A Single-Center Echocardiographic Study
Oguzhan Ay1, Firat Ergin2, Mehmet Baki Beyter3
1Department of Pediatric Cardiology, İzmir Democracy University, Buca Seyfi Demirsoy Training and Research Hospital, İzmir, Türkiye.
Insights
Fontan operation complications like protein-losing enteropathy and thrombosis are linked to changes in inferior vena cava (IVC) and femoral vein (FV) size. Lower IVC/BSA and FV/BSA ratios predict these long-term issues in Fontan patients.
Area of Science:
- Pediatric Cardiology
- Congenital Heart Disease
- Vascular Physiology
Background:
- The Fontan operation is a palliative procedure for single-ventricle congenital heart defects.
- Complications such as protein-losing enteropathy and thrombosis significantly impact long-term outcomes and quality of life.
- Understanding the vascular factors associated with these complications is crucial for improving patient management.
Purpose of the Study:
- To investigate the association between venous structural modifications and complications following Fontan palliation.
- To evaluate the impact of inferior vena cava (IVC) and femoral vein (FV) diameter and flow alterations on Fontan-associated morbidity.
- To determine if venous diameter-to-body surface area (BSA) ratios predict mid- to long-term complications.
Main Methods:
- Retrospective analysis of 25 patients who underwent Fontan palliation at least two years prior.
- Measurement of IVC and femoral vein (FV) diameters and Doppler flow values.
- Calculation of IVC/BSA and FV/BSA ratios and correlation with clinical outcomes and complications.
Main Results:
- A significant difference in age at Fontan was observed between patients with different NYHA functional stages (p=0.019).
- Pathologic microalbumin/creatinine ratio was correlated with elevated pre-Fontan pulmonary artery pressure.
- Lower IVC/BSA and FV/BSA ratios were significantly associated with the presence of complications (p=0.031).
Conclusions:
- Age at Fontan palliation is a risk factor for developing complications.
- Elevated pre-Fontan pulmonary artery pressure is linked to microalbuminuria.
- IVC/BSA and FV/BSA ratios serve as important indicators for predicting mid- to long-term complications after Fontan surgery.
Objective:
This study aims to assess the impact of complications of the Fontan operation, such as protein-losing enteropathy and thrombosis, on patients' quality of life. We hypothesize that alterations in the diameter and flow of the inferior vena cava (IVC) and femoral vein (FV) are associated with these complications. The goal is to evaluate the influence of venous structural modifications on Fontan operation outcomes by analyzing Doppler time measurements of the IVC, FV, aorta (Ao), and femoral artery (FA).
Materials And Methods:
We retrospectively analyzed the recorded images of patients who had undergone Fontan palliation at least two years prior to presentation at our outpatient clinic between January 2022 and January 2023. Patients with chest pain but no cardiac pathology served as controls. Demographic and physical examination data were collected retrospectively. In patients with a normal single-ventricular ejection fraction, we measured the widest IVC diameter and Doppler values, the descending aortic diameter in systole, the widest FV diameter and Doppler values, and the femoral artery diameter in systole.
Results:
The study included 25 Fontan patients: 7 had an extracardiac Fontan, 4 had a fenestrated extracardiac Fontan, and 14 had an intra-extracardiac fenestrated Fontan. A significant difference (p=0.019) was found in the age at Fontan between patients with NYHA stages 1-2 and those with NYHA stages 3-4. A pathologic microalbumin/creatinine ratio (>15) was correlated with pre-Fontan pulmonary artery pressure >15 mmHg. The IVC/BSA (p=0.031) and FV/BSA ratios differed significantly between groups with and without complications, with lower ratios observed in the group with complications.
Conclusion:
Age at Fontan palliation is a risk factor for complications. High pre-Fontan pulmonary pressure is associated with microalbuminuria. IVC/BSA and FV/BSA are inversely associated with mid- to long-term complications following Fontan palliation.
