Intermediate - Cardiac Abnormalities
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Congenital Heart Disease (CHD) is a broad term for a variety of cardiac and vasculature pre-natal defects. They affect about 8-10 of every 1 000 births in the United States. Heart and vascular abnormalities make up around 20% of all congenital malformations. Some of the more common abnormalities are outlined in the table below, in order of frequency.
| Diagram | Abnormality | Epidemiology | Description |
|---|---|---|---|
| Ventricular Septal Defect | 25% of CHD; more frequent in males | Growth failure of the membranous IV septum or endocardial cushions resulting in a lack of closure of the IV foramen. 30-50% close spontaneously; large VSDs result in dyspnoea and cardiac failure in infancy. | |
File:HeartILP draft tetralogyoffallot.jpg Tetralogy of Fallot |
Tetralogy of Fallot | 9-14% of CHD | Classic group of defects: pulmonary stenosis, VSD, dextroposition of aorta, RV hypertrophy. Results in cyanosis. |
File:HeartILP draft transposition.jpg Transposition of the Great Vessels |
Transposition of the Great Vessels | 10-11% of CHD | Aorta arises from the RV with the pulmonary trunk arising from the left. Most common cause of cyanotic heart disease in newborns; surgically corrected. |
| Atrial Septal Defect | 6-10% of CHD; more common in females | Most commonly patent foramen ovale; can also be an ostium secundum defect, and endocardial cushion defect with ostium primum defect, sinus venosus defect, common atrium. Results in cyanosis due to right-to-left shunt. | |
File:HeartILP draft pulmonaryatresia.jpg Pulmonary Atresia File:HeartILP draft pulmonarystenosis.jpg Pulmonary Stenosis |
Pulmonary Atresia & Pulmonary Stenosis | 10% of CHD | Unequal division of trunks causes cusps to fuse to form a dome with a narrow/non existent lumen. Heart-lung transplantation may be the only therapy |
File:HeartILP draft patentda.jpg Patent Ductus Arteriosus |
Patent Ductus Arteriosus | 6-8% of CHD; 2-3 times more common in females; common in preterm newborns | Failure of contraction of the muscular wall of the DA. Spontaneous or surgical closure. |
File:HeartILP draft aorticstenosis.jpg Aortic Stenosis |
Aortic Stenosis | 7% of CHD | Persistence of tissue that normally degenerates. Results in LV hypertrophy, heart murmurs. |
File:HeartILP draft hlh.jpg Hypoplastic Left Heart |
Hypoplastic Left Heart Syndrome | 4-8% of CHD | RV maintains both pulmonary and systemic circulations aided by an ASD. Infants usually die within weeks. |
| Coarctation of the Aorta | 5-7% of CHD | Aortic constriction. Treatment aims at maintaining the ductus arteriosus via prostaglandins. | |
| Partial/Total Anomalous Pulmonary Venous Connection | <4% of CHD; more common in females | Total or partial lack of connection of the pulmonary veins with LA. They open into RA, one of the systemic veins or both. The overloaded pulmonary circuit leads to cyanosis, tachypnoea and dyspnoea. Treatment is via surgical redirection | |
File:HeartILP draft tricuspidatresia.jpg Tricuspid Atresia |
Tricuspid Atresia | 1-3% of CHD | Complete lack of formation of the tricuspid valve with absence of direct connection between the right atrium and right ventricle. Results in cyanosis. |
| Double Outlet Right Ventricle | 1-1.5% of CHD | Both great arteries arise wholly or in large part from the right ventricle. Arrangement of the atrioventricular valves and the ventriculoarterial connections are variable. Clinical manifestations variable. | |
| Interrupted Aortic Arch | Very rare | Gap in ascending and descending thoracic aorta. Treated with prostaglandin to maintain ductus arteriosus followed by surgery. |
