An opening in the wall (septum) between the two upper chambers of the heart (atria). This causes oxygen-rich blood to mix with oxygen-poor blood, increasing the workload on the heart and lungs.

A hole in the wall separating the two lower chambers of the heart (ventricles). Blood flows from the left to the right ventricle, increasing pressure in the lungs and leading to heart failure if not treated.

A narrowing of the pulmonary valve, which restricts blood flow from the right ventricle to the pulmonary artery, causing the heart to work harder to pump blood to the lungs.

A condition where the ductus arteriosus (a blood vessel connecting the pulmonary artery to the aorta in fetal circulation) fails to close after birth. This results in abnormal blood flow between the aorta and the pulmonary artery.

A combination of four defects: ventricular septal defect, pulmonary stenosis, right ventricular hypertrophy, and an overriding aorta. It causes oxygen-poor blood to flow out to the body, leading to cyanosis (bluish skin).

A narrowing of the aorta (the large artery that carries blood from the heart to the body), causing high blood pressure before the narrowing and reduced blood flow beyond it.

The positions of the pulmonary artery and the aorta are switched, meaning oxygen-poor blood is circulated to the body and oxygen-rich blood is sent back to the lungs, making it a life-threatening condition if not corrected.

The left side of the heart is underdeveloped, affecting its ability to pump oxygen-rich blood to the body. This condition requires multiple surgeries or a heart transplant.

The tricuspid valve, which allows blood flow from the right atrium to the right ventricle, is absent or poorly formed. As a result, blood cannot properly flow to the lungs for oxygenation.

The pulmonary veins (which should return oxygenated blood from the lungs to the left atrium) are connected to the wrong side of the heart, mixing oxygen-rich and oxygen-poor blood.

Both the aorta and pulmonary artery arise from the right ventricle, rather than from separate sides of the heart. This causes a mix of oxygen-poor and oxygen-rich blood, leading to cyanosis.

A large hole in the center of the heart where the walls between the atria and ventricles meet. It affects the valves and causes mixing of blood between all four chambers.

A Nuss procedure is a minimally invasive surgery that corrects pectus excavatum, or a sunken chest. This procedure, which has a high success rate, uses one or more metal bars to push a child's breastbone forward to where it belongs.

Aortic valve stenosis is a thickening and narrowing of the valve between the heart's main pumping chamber and the body's main artery, called the aorta. The narrowing creates a smaller opening for blood to pass through. This reduces or blocks blood flow from the heart to the rest of the body.