types of atrial septal defect

Last reviewed 12/2022

Types of atrial septal defect include:

• patent foramen ovale:
• this is present in all neonates and is a potential atrial communication in about 20% of adults
• usually inconsequential since blood is unable to flow from left to right

• secundum atrial septal defect:
• this is the most common form
• it is situated in the middle of the atrial septum

• sinus venosus defect:
• this condition is often associated with anomalous drainage of the right upper and middle lobe pulmonary veins into the superior vena cava or high right atrium

• primum atrial septal defect:
• in this condition the inferior margin of the atrial septum is missing
• this part of the atrial septum anchors the atrioventricular valves
• the mitral valve abnormality may give rise to mitral incompetence

• partial anomalous pulmonary venous drainage:
• in this condition right or left pulmonary veins can drain to the right atrium
• this may occur with or without an associated atrial septal defect