Fontan operation or Total Cavopulmonary Connection (TCPC) is performed for a wide range of congenital cardiac malformations that fall into the category of ‘single ventricle’ – wherein all major systemic veins (superior and inferior vena cava and the hepatic veins) are diverted to the pulmonary arteries, bypassing the right ventricular pump.(1)  Lung mechanics and vascular resistances are crucial determinants of the clinical course after Fontan operation, with pulmonary blood flow being dependent upon the passive flow of blood from systemic veins into the pulmonary arteries. Poor respiratory functions, ventilation/perfusion mismatch, elevated pulmonary vascular pressures and resistances, all contribute to suboptimal hemodynamics after Fontan.(2,3) Physical activity and exercise training is routinely recommended for children and adults following Fontan operation.(4,5) However, the strength of the evidence behind these recommendations is low owing to various methodological limitations including small samples etc., and these studies were conducted in a high-income country setting which may not be relevant in resource poor settings like India.(6,7) Hence, there is a definitive need for a low-cost, culturally acceptable tailored physical activity programme in a low-resource setting like India. Yoga based cardiac rehabilitation has been shown to improve the quality of life in patients following acute myocardial infarction and also, yoga has demonstrated its potential of clinical utility in the wide spectrum of cardiovascular diseases.(8,9)Pilot studies of yogic breathing has been shown to improve lung function and quality of life  in patients with Fontan circulation.(10,11)  

Hence, the specific aims are as follows

1.      Aim 1 : To develop  and validate a yoga programme for patients with single ventricle following Fontan surgery

Approach: The programme will be developed using a structured process involving a literature review and validation among experts. Yogic practices which could influence respiratory mechanics, modulate autonomic functions, lymphatic drainage and increase exercise capacity in various conditions including healthy volunteers, respiratory diseases, cardiovascular diseases and lymphedema will be collated. This will be followed by the validation of developed protocol by the expert committee comprising experts from cardiology, paediatric cardiology and yoga.

2.      Aim 2: To test the efficacy of Yoga based Cardiac rehabilitation programme in patients with single ventricle following Fontan surgery in a pilot clinical trial

Approach: We will recruit 20 patients with single ventricle following Fontan operation for a pre-post clinical trial. The patients will be provided intensive training in yoga (3 sessions a week) and advised to practice 5-7 times a week for three months. The sessions will be delivered over a virtual platform. The efficacy of the programme will be assessed by the cardiovascular and hemodynamic changes using cardiac MRI, respiratory mechanics by pulmonary function tests and psychological profile including anxiety, depression and self-esteem.

3.      Aim 3: To test the feasibility and acceptability of various yoga practices prescribed in the yoga programme

Approach: The participants in the trial will be requested to provide information on the feasibility and acceptability of each of the individual yoga practices prescribed every 15 days through a structured questionnaire. In addition, the yoga trainer will report on the ability of the participants to perform each of the practices every two weeks. These data will be essential to modify the yoga programme, if required. We will also interview the participants and their caregivers to collect data on acceptability and feasibility of the yoga programme.