Exercise limitation in patients with Fontan circulation: a review

Abstract

The aim of the current literature study was to perform a literature review of the factors contributing to exercise limitation and physiological response to exercise in patients with Fontan circulation. In patients with Fontan circulation, peak oxygen uptake ranged from about 14.4 to 32.3 ml/min/kg, and showed a slowed acceleration in the kinetics of oxygen uptake at the onset of exercise. Peak heart rate during exercise was decreased to an average of 153 +/- 10 bpm and arterial oxygen saturation was also decreased at peak exercise, with an average of 89.5 +/- 1.94%. Cardiac output was subnormal, owing to reduced stroke volume, heart rate response and affected pulmonary venous return. Ventilatory anaerobic threshold was below normal values. Moreover, the ventilatory equivalent for carbon dioxide was found to be higher. Patients with Fontan circulation possess a unique physiological response to exercise. Although there is a wide range in exercise capacity among patients, all patients have reduced tolerance to exercise. Cardiac, pulmonary, and muscular factors might play a role in reduced exercise capacity and this distinct response to exercise.

What determines the quality of life of adult patients after Fontan procedure?

“…Additionally, chronotropic incompetence occurs during exercise in patients with Fontan circulation [20], with an HR consistently lower than in normal subjects. This situation is due to abnormal reflex control of HR and adrenergic dysfunction [20,22]. Heart rate plays an important role in determining the cardiac output in Fontan circulation during exercise [19,20], when autonomic dysfunction of the sinus node leads to a relatively low HR [23].…”

“…Exercise increases the cardiac output up to 5-fold or more due to the augmentation of the above components. In Fontan circulation, the lack of a pulmonary pump reduces the return from pulmonary circulation [20]. As a result, preload reserve of the systemic ventricle is reduced or absent.…”

“…Cardiac output in Fontan circulation at rest is 70% of cardiac output of the biventricular heart [21]. Additionally, chronotropic incompetence occurs during exercise in patients with Fontan circulation [20], with an HR consistently lower than in normal subjects. This situation is due to abnormal reflex control of HR and adrenergic dysfunction [20,22].…”

“…This situation is due to abnormal reflex control of HR and adrenergic dysfunction [20,22]. Heart rate plays an important role in determining the cardiac output in Fontan circulation during exercise [19,20], when autonomic dysfunction of the sinus node leads to a relatively low HR [23]. Physical functioning, including vigorous activities like running, lifting heavy objects, or strenuous sports, and mild activities like bending, kneeling, lifting, or carrying groceries, depends on maximal HR reached at the peak of exercise.…”

Dynamic of bio-geometric profile indicators of children’s with functionally one ventricle posture at stage of physical rehabilitation

“…Scientists note that patients with FOV lag in physical development [3] have reduced functional potentials of respiratory system [9,12,19,22] and tolerance to physical loads [11,14,24,30]. As on to day the problems of physical rehabilitation of children with CHD are paid insufficient attention to.…”