Problems with the Walls 1. Atrial Wall The wall between the right atrium and left atrium is called Atrial Septum. Please note that the word "septum" in Greek means "wall." If there is a hole in that wall it is called an Atrial Septal Defect (ASD). The operation to fix this defect is the Patch Operation. 2. Ventricular Wall The wall between the front two chambers (between the two ventricles) is called Ventricular Septum. If there is a hole in this wall it is called Ventricular Septal Defect (VSD). The operation to fix this defect is the Patch Operation.

Problems with the Chambers 1. Right Ventricle If the right ventricle is small and weak, this condition is called Hypoplastic Right Heart or Hypoplastic Right Ventricle. It happened because the tricuspid valve guiding the blood from the right atrium to the right ventricle did not open in the very early embryonic weeks of the baby's life, and so no blood came through to make the right ventricle grow. 2. Left Ventricle If the left ventricle is small and weak, this condition is called Hypoplastic Left Ventricle or Hypoplastic Left Heart Syndrome. It happened because the mitral valve guiding the blood from the left atrium to the left ventricle did not open in the very early embryonic weeks of the baby's life, and so no blood came through to make the left ventricle grow.

Problems with the Hallways The hallways leading away from the heart: 1. Aorta If this hallway is narrowed as it makes the bend to go down to the body it is called Coarctation of the Aorta. 2. Pulmonary Artery If the pulmonary artery is narrowed as it branches to either the right or left lung this condition is called Branch Pulmonary Artery Stenosis. When these 2 main hallways leading away from the heart are swapped or transposed, it is called Transposition of Great Arteries. Click here to see the operation to fix this defect. The hallways emptying into the heart: 3. Pulmonary Veins If the Pulmonary Veins that normally lead to the left atrium are rerouted to the wrong vein, this condition is called Total Anomalous Pulmonary Venous Connection.

Problems with the Plumbing When the main coronary artery originates from the Pulmonary Artery instead of the Aorta, this defect is called Anomalous Origin of the Coronary Artery from the Pulmonary Artery.

Problems with the Doors 1. Tricuspid Valve The Tricuspid Valve is located between the right atrium and right ventricle. If this door is not developed this condition is called Atresia (Tricuspid Valve Atresia). There is a 3-step procedure to fix this defect: • Stage 1: Shunt Operation • Stage 2: Glenn Operation • Stage 3: Fontan Operation Since the door did not develop in the baby before birth there was no blood coming from the right atrium to the right ventricle so the right ventricle became underdeveloped (hypoplastic right ventricle). If the tricuspid door is displaced downward from it's usual location, this will result in the right atrium becoming excessively large and the right ventricle small and underdeveloped. This condition is called Ebstein Anomaly. 2. Mitral Valve The mitral valve is the door between the left atrium and the left ventricle. If the mitral valve does not develop during the very early gestation weeks, the blood in the left atrium will not flow to the left ventricle, and therefore the left ventricle will be small and underdeveloped (Hypoplastic Left Heart Syndrome). There is a 3-step procedure to fix this defect: • Stage 1: Norwood Operation • Stage 2: Glenn Operation • Stage 3: Fontan Operation 3. Pulmonic Valve The pulmonic valve is the door located between the right ventricle and the main pulmonary artery. If this door is a little bit small (depending on how small it is) we call this condition stenosis (Pulmonic Valve Stenosis). If it does not develop at all we call this condition atresia (Pulmonic Valve Atresia). 4. Aortic Valve The aortic valve is the door located between the left ventricle and the aorta. If the valve is small this condition is called stenosis (Aortic Valve Stenosis). If this valve does not develop at all this condition is called atresia (Aortic Valve Atresia).

Problems Involving More Than One Part of the Heart 1. Tetralogy of Fallot This involves a hole between the ventricles, a narrow pulmonary hallway, an overriding aortic hallway, and enlargement and thickening of the right ventricular wall. Click here to see the operation to fix this defect. 2. Truncus Arteriosus. Part of the wall between the front large heart chamber is missing. An overriding aorta, which means the door from the left ventricle (aortic valve) originates from both front chambers. Click here to see the operation to fix this defect. 3. Common Atrioventricular Canal • Pulmonary Artery Band • Operation to Fix Defect 4. Ductus Arteriosus • Clip Operation • Coil Operation