Importance of Physical Activity and Exercise in Paediatric Fontan Patients

The Fontan circulation, creating a total cavopulmonary connection, has dramatically improved the survival of individuals with a single functional ventricle. The direct venous return to the lungs without a subpulmonary pump allows the single ventricle to be dedicated to the systemic circulation, but also impacts cardiovascular and respiratory functions. Involvement in physical activity or exercise requires an increase in cardiac output to meet the increased metabolic demands, but the Fontan circulation has limited ability to sustain the high cardiac output required for vigorous exercise. The missing subpulmonary pump, increased venous pressure and pulmonary vascular resistance, and abnormal oxygen utilization contribute to limited exercise capacity in these patients.¹ Given these limitations, it is not surprising that the maximal exercise capacity of paediatric Fontan patients is approximately 65% of what would be predicted for healthy children of the same age.² Considering the known limitations of a Fontan circulation and the historical lack of data regarding the long-term sequelae of this abnormal physiology, it is not surprising that paediatric Fontan patients often report that they have been advised to avoid vigorous activity.³ Historically, expert guidelines severely restricted their competitive sport participation.⁴ A lack of consensus regarding the type and extent of exercise training for these patients persisted until more recent publications regarding patient safety and the functional benefits of regular exercise.^5,6