Atrial septal defect and exercise capacity: value of cardio- pulmonary exercise test in assessment and follow-up

Nearly four decades ago, the World Health Organization stated that functional capacity explorations best reflected the impact of a chronic disease on quality of life. Today, cardio-pulmonary exercise test (CPET) is recommended in the follow-up of patients with congenital heart diseases (CHDs). Indeed, the maximum oxygen uptake (VO_2max) and the ventilatory efficiency (VE/VCO2 slope) correlate with both the prognosis and the quality of life in this population. Atrial septal defects (ASDs) represent the second most frequent CHD and are usually considered as simple CHDs. However, the exercise capacity of ASD patients may be impaired. Therefore, the CPET provides important information in assessment and follow-up of patients with ASDs, for both children and adults. Exercise capacity of patients with unrepaired ASDs depends on the importance of the shunt, the right ventricular (RV) function and volume overload, the level of pulmonary arterial pressure, and the occurrence of arrhythmias. For repaired ASDs, exercise capacity also depends on the delay before closure and the type of procedure (catheter or surgery). In most cases, the exercise capacity is nearly normal and CPET contributes to promote sports participation. In addition, a regular CPET follow-up is necessary to evaluate the occurrence, severity and physiological mechanisms of comorbidities, i.e., heart failure, pulmonary hypertension and arrhythmia. Furthermore, CPET follow-up in patients with ASDs may detect early onset of muscular deconditioning, for which cardiac rehabilitation may be considered.