What is the most common cardiac defect found in adults?

The most common cardiac defect found in adults is the atrial septal defect (ASD). This defect occurs when there is an opening in the septum that separates the two upper chambers of the heart (the atria). While many individuals with a small ASD may not experience significant symptoms or require intervention, as they age, the shunting of blood between the left and right atria can lead to complications, such as right heart volume overload, atrial arrhythmias, and pulmonary hypertension. These factors often draw attention to the defect in adulthood, making it one of the most commonly diagnosed congenital heart defects in this age group.

In contrast, ventricular septal defects are more prevalent in children, as they usually present earlier in life and can lead to more immediate symptoms, necessitating surgical intervention. Mitral valve prolapse, while a relatively common condition and often asymptomatic, is not classified as a congenital defect, but rather as a structural abnormality that may not necessarily have been present at birth. Aortic stenosis can occur as a congenital defect but is more often seen as a degenerative condition in older adults rather than the most common defect overall. Thus, the recognition of atrial septal defects in adults and their potential complications contributes to their