Metabolic Remodeling in Fontan Patients

Study Overview
=================
Brief Summary
-----------------
Assessment of metabolic alterations in adult Fontan patients with a dominant left ventricle with the help of serum examinations (Metabolomics). The aim is to find a tool for the completion of the (semi-)invasive monitoring of Fontan hemodynamics.

Detailed Description
-----------------
Patients who are born with just one single heart chamber need to undergo surgical therapy allowing the single heart chamber to pump the blood into the systemic circulation and allowing the blood to flow passively to the lungs (Fontan circulation). Regular ultrasound, cardiopulmonary exercise testing, and invasive diagnostic tools (catheterization, general anaesthesia needed) are necessary to early find out cardiac, vascular, or circulatory impairment. It is still very difficult to diagnose and therapy failure of this Fontan system early enough. It is reported that in patients with a failing two-chambered heart, the energy source for the heart and the body in general switches from the use of lipids to the use of sugar and ketone bodies. First studies show decreased concentrations of membrane lipids in Fontan patients with a left dominant ventricle, and the energy metabolism has not been focused yet in those patients. The investigators hypothesize that there are differences in the pattern of the structural metabolism in adult Fontan patients with a left-dominant vs. a right-dominant ventricle. Furthermore the investigators hypothesize that there are alterations in the energy metabolism in adult Fontan patients in comparison to healthy two-chambered controls, and that those alterations correlate with the grade of impairment of cardiopulmonary function. With the help of a special biochemical examination (mass spectrometry-based Metabolomics study) blood of Fontan patients will be analyzed, and the results will be correlated with the results of ultrasound and cardiopulmonary exercise testing. The aim of this study is to establish sensitive blood markers indicating cardiac, vascular, circulatory or further organ dysfunction in Fontan patients. This should allow optimal Fontan system monitoring with an optimal timing of an additional invasive diagnostic catheterization and of nutritional, medical or interventional therapy.

Official Title
-----------------
Metabolic Remodeling in Fontan Patients: a Metabolomics Study

Conditions
-----------------
Congenital Heart Disease, Metabolism Disorder

Intervention / Treatment
-----------------
* Diagnostic Test: Metabolomics


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Fontan circulation (right systemic ventricle), biventricular heart with heart failure resp. ≥ 18 years Written informed consent of patients 8 hours fasting period before blood sample Exclusion Criteria: Intake of medication directly affecting metabolic (e.g. metabolism of lipids (statine)) or hemodynamic state (e.g. beta-blockers, sildenafil) (other than angiotensin converting enzyme (ACE)-inhibitors and anticoagulation therapy) Cachectic disease Non-congestive hepatic or renal dysfunction (Inherited) metabolic disorders
Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
Accepts Healthy Volunteers

Study Plan
=================
How is the study designed?
-----------------

Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Fontan patients<br>The serum of Fontan patients is compared to the serum of healthy biventricular controls (Metabolomics) | Diagnostic Test: Metabolomics<br> <br> |
| Healthy biventricular controls<br>The serum of Fontan patients is compared to the serum of healthy biventricular controls (Metabolomics) | Diagnostic Test: Metabolomics<br> <br> |

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Metabolism of lipids | Measurement of the serum concentration of the extended metabolism of lipids using the technique of Metabolomics (AbsoluteIDQ p180 kit, Biocrates Life Sciences AG, Innsbruck, Austria) | blood sampling at one single point of time (baseline/day 1) in the context of a planned patient presentation at the pediatric cardiology outpatient clinic (without assessment of changes) | 
| Metabolism of amino acids and related compounds | Measurement of the serum concentration of the extended metabolism of lamino acids using the technique of Metabolomics (AbsoluteIDQ p180 kit, Biocrates Life Sciences AG, Innsbruck, Austria) | blood sampling at one single point of time (baseline/day 1) in the context of a planned patient presentation at the pediatric cardiology outpatient clinic (without assessment of changes) | 
| Metabolism of carbohydrates | Measurement of the serum concentration of the extended metabolism of carbohydrates using the technique of Metabolomics (AbsoluteIDQ p180 kit, Biocrates Life Sciences AG, Innsbruck, Austria) | blood sampling at one single point of time (baseline/day 1) in the context of a planned patient presentation at the pediatric cardiology outpatient clinic (without assessment of changes) | 
| Metabolism of ketone bodies | Measurement of the serum concentration of ketone bodies using the technique of Metabolomics (AbsoluteIDQ p180 kit, Biocrates Life Sciences AG, Innsbruck, Austria) | blood sampling at one single point of time (baseline/day 1) in the context of a planned patient presentation at the pediatric cardiology outpatient clinic (without assessment of changes) |