Atrial septal defect

This is a congenital condition which is commonly diagnosed in adulthood. There is an increased incidence in females.

Atrial septal defect (ASD) is a common congenital abnormality that occurs in the form of:

• ostium secundum,
• ostium primum,
• sinus venosus,
• coronary sinus defects (very rarely)

The communication between the atria allows left-to-right shunting of blood. The low pulmonary vascular resistance and the distensibility of the right ventricle leads to an increase in right heart output.

After the age of about 30 years old there may be an increase in vascular resistance which can give rise to pulmonary hypertension. Atrial fibrillation may then be seen.

Pathophysiologic consequences of ASDs typically begin in adulthood

• these consequences include:
  • arrhythmia,
  • paradoxical embolism,
  • cerebral abscess,
  • pulmonary hypertension,
  • right ventricular failure

ASD and ECG Findings - for further information click here