Normal Heart

Congenital Heart Defects

1. Patent Ductus Arteriosus The ductus arteriosus connects the main pulmonary artery to the aorta. In utero, it allows the blood leaving the right ventricle to bypass the pulmonary circulation and pass into the descending aorta.

2. Ventricular Septal Defect A hole in the septum between the 2 ventricles. The size of the defect varies, from pinhole to complete absence of septum. Pulmonary vascular resistance (PVR) being less than systemic vascular resistance (SVR), it creates a left-to-right shunt, increasing pulmonary blood flow.

3. Atrial Septal Defect Consists of a hole in the septum between the 2 atrium. As pulmonary vascular resistance (PVR) decreases, it creates a left-to-right shunt with right ventricular volume overload and hypertrophy.

4. Atrioventricular Canal Defect An opening in the septum between the 2 atrium and the 2 ventricles which allows oxygen rich blood to pass from the left ventricle through the opening in the septum and then mix with the oxygen-poor blood in the right ventricle. .

5. Double Outlet Right Ventricle A congenital defect in which both the pulmonary artery and the aorta arise from the right ventricle.

1. Coarctation of the Aorta A localized constriction of the aorta that usually occurs at the junction of the transverse aortic arch and the descending aorta in the vicinity of the ductus arteriosus.

2. Critical Aortic Stenosis A lesion that results in obstruction of blood flow from the left ventricle to the aorta.

3. Interrupted Aortic Arch It is the complete discontinuity between the proximal and distal portions of the aortic arch

4. Hypoplastic Left Heart Syndrome A clinical spectrum that is characterized by hypoplasia of the left ventricle, severe mitral valve stenosis or atresia, or severe aortic valve stenosis or atresia, and hypoplastic ascending aorta and transverse aortic arch

1. Tetralogy of Fallot A congenital heart defect with four anomalies including: • VSD • Right ventricular hypertrophy

(thickening of the muscle walls of the right ventricle due to the increased pressure in the RV). Causes a characteristic boot shaped appearance on x-ray.

• Right ventricular outflow tract obstruction (pulmonary arterial stenosis or pulmonary atresia which creates an obstruction of blood flow from the right ventricle to the pulmonary artery)

• Overriding aorta (the aortic valve is enlarged and appears to arise from both the left and right ventricles instead of the left ventricle only).

2. Truncus Arteriosus Characterized by a single arterial trunk arising from the normally formed ventricles by means of a single semilunar valve (ie, truncal valve).

3. Total Anomalous Pulmonary Venous Return Drainage of all the pulmonary veins is into the right atrium either directly or by way of the systemic veins.

4. Ebstein’s Anomaly An abnormality of the tricuspid valve where two leaflets of the valve are displaced downward into the right ventricle and the third leaflet is elongated and may be tethered to the wall of the chamber

1. Transposition of the Great Arteries Arises when the aorta arises from the right ventricle and ejects deoxygenated blood to the body; the pulmonary artery arises from the left ventricle and recirculates oxygenated blood to the lungs

2. Tricuspid Atresia Congenital absence or agenesis of the tricuspid valve

3. Pulmonary Atresia A complete agenesis of the pulmonary valve which prevents blood from flowing forward from the right ventricle to the lungs.