Atrial Septal Defect Incidence Rates Explored

Atrial Septal Defect (ASD) is one of the most commonly diagnosed congenital heart conditions in clinical practice. The overall incidence of ASD falls within the range of several tenths of a percent. This type of heart defect can be broadly categorized into two main types: ostium primum defects and ostium secundum defects.

Classification of Atrial Septal Defects

Ostium secundum defects, which are more prevalent, can be further classified based on their anatomical location. These include superior vena cava-type defects, inferior vena cava-type defects, and defects near the coronary sinus. Collectively, these subtypes account for approximately 5% to 10% of all ASD cases, making them relatively less common.

The Prevalence of Central Atrial Septal Defect

Among all types, the central atrial septal defect—also known as the ostium secundum type—is located in the middle portion of the interatrial septum. This defect typically develops at the fossa ovalis, a thin-walled area in the fetal heart that normally closes after birth. Central ASD represents the largest proportion of all secondary atrial septal defects, accounting for roughly 70% of cases.

Given its high prevalence among congenital heart diseases, central atrial septal defect is considered one of the most frequently occurring heart anomalies at birth. Understanding the distribution and characteristics of different ASD types is crucial for accurate diagnosis and effective treatment planning.