Impact of Exercise Training on Single Ventricle Function in Paediatric Fontan Patients

The goal of this observational study is to learn about how a prescribed Exercise Training Program would affect children living with a Fontan circulation.From birth, the children who are born with single functioning ventricle will undergo 3-staged Fontan surgery to achieve a unique Fontan circulation, supported by one functioning ventricle. With advancement in surgical technique and medical care, there are increasing number of children living with Fontan circulating surviving into adulthood.A significant number of these individuals develop complications in their adulthood due to problems related to this unique circulation, including reduced exercise tolerance, heart failure, abnormal heart rhythm or premature death. Many of these children have acquired sedentary lifestyle, and may have lower self-perceived health related quality of life.Exercise training is a well-established therapy used in adult population with heart failure. It has been shown to be safe in children with congenital heart disease and with Fontan circulation, it improves their aerobic exercise capacity which is associated with better outcomes.The main question[s] it aims to answer are the impact of a Exercise Training program on:Single ventricle functionExercise capacitySelf-perceived quality of lifeSkeletal muscle massParticipants will be given a 20-weeks exercise program, 3 sessions of 30 minutes workout weekly, to carry out at home. The following tests will be performed prior to starting and upon completion of the exercise program:EchocardiogramCardiopulmonary exercise testBody composition scan using a bio-impedance analyserQuality of life questionnaires

Inclusion Criteria:Patients with Fontan circulation, age range 8 to 18 yearsAbility to perform a cardiopulmonary exercise stress test (CPET)Free from acute or chronic respiratory illness and/or conditions that might affect exercise performanceWho have had a Fontan operation at least six months prior.Exclusion Criteria:Existing neuro-disability i.e. with paresis post cerebrovascular accidentNeurodevelopmental issue with inability to comply with commands.Documented life-threatening arrhythmia without implantable cardioverter defibrillatorModerate or severe atrio-ventricular valve regurgitationModerate or severe ventricular dysfunction by echocardiography examsAcute inflammatory cardiac diseasedocumented coronary artery stenosis and/or myocardial ischaemiaHeart failure requiring hospitalisation in the past yearEvidence of systemic venous pathway obstruction by echocardiography or catheterisationResting oxygen saturation < 90%Systemic ventricular outflow tract stenosis with peak resting systolic gradient > 50mmHg