heart author" faq
Tetralogy of Fallot


It is characterized by a large ventricular septal deftect (VSD), an aorta that overrides the left and right ventricles, obstruction of the right ventricular (RV) outflow tract, and RV hypertrophy (increased wall thickness).

As obstruction in RV outflow tract increases, more blood is shunted through the VSD to the left side of the heart to cause more cyanosis (see fig 23C).

Increases in resistance to flow in the general arteries of the body causes less shunting, and decreases cause more shunting to the left.

Symptoms in adults include shortness of breath and limited exercise tolerance.

Complications include brain abscesses, strokes and heart infections.

Such patients may have enlargement of the distal ends of their fingers called clubbing.

Most patients without surgical correction die in childhood.

Echocardiography can establish the diagnosis. Color Doppler can visualize the VSD.

Heat catherterization can confirm the diagnosis.

Surgical repair is recommended to relieve symptoms and to improve survival.

Complete surgical correction (closure of the VSD and relief of RV outflow obstruction is performed currently when patients are very young.

Patients are at risk for heart infections and should thus receive prevention with antibiotics before dental or elective surgical procedures.

Even with repair these patients have a poorer survival rate (apparently due to cardiac causes such as arrhythmias).