Notes

Etiology: While factors such as poor maternal nutrition, viral illness or genetic disorders might increase the risk of this condition, in most cases the cause of tetralogy of Fallot is unknown.

Diagnosis testing:
~Echocardiography
~Electrocardiogram
~Chest X-ray
~Pulse oxymetry

Signs and Symptoms:
1. Pulmonary valve stenosis: Narrowing of the pulmonary valve. This reduces blood flow to the lungs. and may also affect the muscle beneath the pulmonary valve.
2. Ventricular septal defect. A hole in the wall that separates the two ventriclular chambers of the heart. It allows deoxygenated blood in the right ventricle to flow into the left ventricle and mix with oxygenated blood fresh from the lungs. Blood from the left ventricle also flows back to the right ventricle in an inefficient manner, which reduces the supply of oxygenated blood to the body and eventually can weaken the heart
3. Overriding aorta. Normally the aorta branches off the left ventricle. In ToF, the aorta is shifted slightly to the right and lies directly above the ventricular septal defect. In this position the aorta receives blood from both the right and left ventricles, mixing the oxygen-poor blood with the oxygen-rich blood.
4. Right ventricular hypertrophy. When the heart's pumping action is overworked, it causes the muscular wall of the right ventricle to thicken. Over time this might cause the heart to stiffen, become weak and eventually fail.

Daily Life: ToF is treated after diagnosis, so most infants will live active, healthy lives after surgery. However, they will need regular follow-up visits with a cardiologist to monitor their progress and check for other health conditions. As adults, they may need more surgery or medical care for other possible problems.

Treatment:
Intracardiac repair: Surgeon places a patch over the ventricular septal defect to close the hole between the lower ventricular chambers of the heart. The narrowed pulmonary valve is repaired or replaces and the pulmonary arteries are widened.
Temporary surgery: Some infants need this surgery before intracardiac repair. The surgeon creates a bypass between a large artery that branches off from the aorta and the pulmonary artery.
The child will also have to continue to seek care from a cardiologist specialized in congenital defects.

Demographic Affected:
ToF occurs in approximately one in every 2000 births. In the United States, appx. 10 percent of congenital heart disease is ToA. Boys are slightly more likely to have this malformation than girls.