Congenital Heart Disease (CHD) refers to conditions involving the heart or nearby large blood vessels present at birth. The term "congenital" indicates the timing of the condition, not its cause. CHD is the most common major birth defect, affecting about 1% of newborns (approximately 8 per 1,000). This statistic is likely underestimated as it excludes some prevalent conditions, such as:- Ductus arteriosus in premature infants (a temporary issue)- Bicuspid aortic valve (typically, this valve has three cusps)- Mitral valve prolapse (a drooping of a heart valve)- Peripheral pulmonary stenosis (narrowing of lung vessels far from the heart)There are numerous types of congenital heart disease. Below is a summary of the primary categories and notable conditions within each:**Heart Detour Defects:**These defects allow blood to flow abnormally between the heart's right and left sides, often due to a defect in the wall (septum) that separates the two sides, resulting in "a hole in the heart." The two main types of septal defects are:- Atrial septal defect (ASD)- Ventricular septal defect (VSD)Less common defects affecting blood flow routes include:- Eisenmenger's syndrome- Atrioventricular (A-V) canal defect, also known as endocardial cushion defect**Detour Defects External to the Heart:**Patent ductus arteriosus (PDA) is a type of blood-routing issue located outside the heart. It involves a duct that connects the pulmonary artery to the aorta, remaining open (patent) after birth, allowing blood to flow back into the lungs instead of through the aorta to the body.**Obstructive Defects:**These defects restrict blood flow within the heart or its nearby large vessels due to narrowing (stenosis) that partially or completely blocks blood flow. Common forms include:- Pulmonary (valvular) stenosis- Coarctation of the aortaLess frequent obstructive defects include:- Bicuspid aortic valve- Ebstein's anomaly**Cyanotic Defects ("Blue Babies"):**Certain CHDs result in cyanosis, where blood with lower-than-normal oxygen levels circulates through the body, causing a bluish tint to the skin. Types include:- Tetralogy of Fallot- Transposition of the great arteries- Tricuspid atresia- Truncus arteriosus- Total anomalous pulmonary venous return- Pulmonary atresia**Hypoplastic Heart Defects:**These involve underdeveloped or hypoplastic areas of the heart, such as:- Right heart hypoplasia- Left heart hypoplasia**Other Developmental Heart Defects:**Additional developmental heart defects can occur, such as:- Single ventricle (only one ventricle is present)- Double outlet right ventricle (both the aorta and pulmonary artery originate from the right ventricle)Alternative terms for congenital heart disease include congenital heart defect, congenital heart malformation, congenital cardiac defect, and congenital cardiovascular malformation. For a more detailed exploration of this topic, refer to the comprehensive article on Congenital Heart Disease.
