Medical Encyclopedia

 

Medical Encyclopedia

Other encyclopedia topics:  A-Ag  Ah-Ap  Aq-Az  B-Bk  Bl-Bz  C-Cg  Ch-Co  Cp-Cz  D-Di  Dj-Dz  E-Ep  Eq-Ez  F  G  H-Hf  Hg-Hz  I-In  Io-Iz  J  K  L-Ln  Lo-Lz  M-Mf  Mg-Mz  N  O  P-Pl  Pm-Pz  Q  R  S-Sh  Si-Sp  Sq-Sz  T-Tn  To-Tz  U  V  W  X  Y  Z  0-9 

Tetralogy of Fallot

Contents of this page:

Illustrations

Heart, section through the middle
Heart, section through the middle
Tetralogy of Fallot
Tetralogy of Fallot
Cyanotic 'Tet spell'
Cyanotic 'Tet spell'

Alternative Names    Return to top

TET; TOF

Definition    Return to top

Tetralogy of Fallot refers to a group of four types of heart defects present at birth (congenital).

Causes    Return to top

Tetralogy of Fallot is classified as a cyanotic heart defect because the condition causes low oxygen levels in the blood, which leads to cyanosis (a bluish-purple coloration to the skin).

The classic form of Tetralogy includes 4 defects within the heart structures:

At birth, infants may not show the signs of the cyanosis, but later may develop sudden frightening episodes (called "Tet spells") of bluish skin from crying or feeding.

Tetralogy of Fallot is considered rare. Patients with tetraology of Fallot have a higher incidence of major non-heart congenital defects.

The cause of most congenital heart defects is unknown. Multiple factors seem to be involved. Prenatal factors associated with higher than normal risk for this condition include maternal rubella or other viral illnesses during pregnancy, poor prenatal nutrition, maternal alcoholism, mother over 40 years old, and diabetes.

There is a high incidence of chromosomal disorders in children with tetralogy of Fallot, such as Down syndrome and Di George's syndrome (a partial gene deletion that results in heart defects, low calcium levels, and immune deficiency.)

Symptoms    Return to top

Exams and Tests    Return to top

A physical examination with a stethoscope almost always reveals a heart murmur.

Tests may include:

Treatment    Return to top

Surgery to repair heart defects is always done when the infant is very young. Sometimes more than one surgery is needed. The first surgery may be done to help increase blood flow to the lungs. Surgery to correct the problem may be done at a later time. (Generally, a definitive corrective surgery is performed in the first few months of life.) Corrective surgery is done to widen part of the narrowed pulmonary tract and close the ventricular septal defect.

Tips for parents of children with tetralogy of Fallot:

Outlook (Prognosis)    Return to top

Most cases can be corrected with surgery. Babies who have surgery usually do well. Ninety percent survive to adulthood and live active, healthy, and productive lives. Without surgery, death usually occurs by the time the person reaches age 20.

Patients who have continued, severe leakiness of the pulmonary valve may need the valve replaced.

Regular follow up with a cardiologist to monitor for life-threatening arrhythmias (irregular heart rhythms) is recommended.

Possible Complications    Return to top

When to Contact a Medical Professional    Return to top

Call your health care provider if new unexplained symptoms develop or if the patient is having an episode of cyanosis (blue skin).

Prevention    Return to top

There is no known prevention.

References    Return to top

Zipes DP, Libby P, Bonow RO, Braunwald E, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine, 8th ed. St. Louis, Mo; WB Saunders; 2007.

Update Date: 12/10/2007

Updated by: Mark A Fogel, MD, FACC, FAAP, Associate Professor of Pediatrics and Radiology, Director of Cardiac MR, The Children's Hospital of Philadelphia. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

A.D.A.M. Logo

The information provided herein should not be used during any medical emergency or for the diagnosis or treatment of any medical condition. A licensed physician should be consulted for diagnosis and treatment of any and all medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- they do not constitute endorsements of those other sites. Copyright 1997-2009, A.D.A.M., Inc. Any duplication or distribution of the information contained herein is strictly prohibited.