Atrial Septal Defect - Exercise Capacity and Pulmonary Hypertension

1. Background Patients born with atrial septal defect (ASD) in the heart, have long been assumed healthy after closure of their defect. However, recent studies show, that despite closure of the ASD the risks of arrhythmia, stroke and pneumonia are increased. It is also shown that ASD patients die earlier than the background population and the cause of death is most often cardiac. The reason for this higher mortality and morbidity is unknown and the scope of this thesis.
2. Aim To determine if closed (both surgical and transcatheter) ASD patients have reduced exercise capacity, impaired right and left ventricular function, increased pressure in the pulmonary system, and reduced heart rate variability when compared with healthy controls. The investigators will also examine if method of closure is of importance.
3. Hypothesis

Primary endpoint:

The shunting effect alters the hemodynamic in the ASD heart resulting in lower cardiopulmonary exercise capacity when compared with healthy controls.

Secondary endpoints:

The shunting effect alters the hemodynamic in the ASD heart when compared with healthy controls resulting in

• Impaired force frequency relationship with a reduction in contractility at optimal heart rate.
• Increased pulmonary arterial pressure.
• Twice as many ASD patients with decreased heart rate variability.