For some patients, certain types of surgery can result in limited exercise tolerance. An exercise EKG, which assesses the heart's response to stress or exercise, can be used to test exercise tolerance, as well as to gather data that can shed light on the long term effects of surgery.
Patients who have undergone Fontan surgery can suffer from reduced peak oxygen consumption, which limits their physical capabilities.
Boston Children’s researchers conducted a study to assess the evolution of exercise tolerance in patients with previous Fontan surgery. Patients with previous Fontan surgery underwent cardiopulmonary exercise testing between November 2002 and January 2009. They were required to have completed at least two tests, with adequate levels of effort, at least six months apart.
Most of the decline in exercise function occurred in patients under the age of 18. Thereafter, the rate of decline was less significant.
Researchers concluded that although the exercise function of previous Fontan patients tends to decline during late adolescence, it appears to stabilize during early adulthood, which presented new hope for Fontan patients and their families.