Which is the most common acyanotic congenital heart defect?

Which is the most common acyanotic congenital heart defect?

• A. Patent ductus arteriosus
• B. Coarctation of the aorta
• C. Atrial septal defect
• D. Ventricular septal defect

Answer: (D)

Left-to-right shunts that do not cause cyanosis are the acyanotic congenital heart defects, and among these, a ventricular septal defect is the most common. A VSD is a hole in the ventricular septum, most often in the membranous region, which allows blood to flow from the left ventricle to the right during systole. Because these defects occur frequently and many are small enough to remain asymptomatic or close on their own, they appear very often in pediatric practice and are the most common acyanotic lesion seen. Clinically, a VSD often presents with a holosystolic murmur at the left lower sternal border. The presentation depends on size: small defects may be quiet, while large defects cause increased pulmonary blood flow and heart failure signs in infancy. While patent ductus arteriosus and atrial septal defects are also acyanotic, they are less common as a group and have different murmur features and age-related patterns. That combination of high frequency and typical presentation makes ventricular septal defect the best answer for the most common acyanotic congenital heart defect.

Left-to-right shunts that do not cause cyanosis are the acyanotic congenital heart defects, and among these, a ventricular septal defect is the most common. A VSD is a hole in the ventricular septum, most often in the membranous region, which allows blood to flow from the left ventricle to the right during systole. Because these defects occur frequently and many are small enough to remain asymptomatic or close on their own, they appear very often in pediatric practice and are the most common acyanotic lesion seen.

Clinically, a VSD often presents with a holosystolic murmur at the left lower sternal border. The presentation depends on size: small defects may be quiet, while large defects cause increased pulmonary blood flow and heart failure signs in infancy. While patent ductus arteriosus and atrial septal defects are also acyanotic, they are less common as a group and have different murmur features and age-related patterns. That combination of high frequency and typical presentation makes ventricular septal defect the best answer for the most common acyanotic congenital heart defect.