Your symptoms may be related to your atrial septal defect
.An atrial septal defect is due to persistence of a hole(foramen ovale) in the wall(septum)between the right and the left atrium of the heart.Usually the foramen ovale closes spontaneously after birth but in some cases the foramen ovale does not close causing blood to flow from the left atrium into the right atrium
causing an increased blood flow into the lung(shunting of blood from left to right).So the oxygenated blood which is to be supplied to the whole body is partly shunted back into the lungs.This causes fatigue
and exertional dyspnoea and occasionally syncope.Increasing age can increase the risk of your having a stroke due to an embolic event.Nowadays your condition can be easily treated through endovascular closure of the defect .This procedure involves introducing a guidewire and delivery sheath through a small incision in the groin.An occluder device is introduced through the delivery sheath and guided into position using fluoroscopy
and echo.The occluder device isexpanded within the atrial septal defect to close it.People can usually go home on the next day.