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$Unique_ID{BRK04312}
$Pretitle{}
$Title{Ventricular Septal Defects}
$Subject{Ventricular Septal Defects Roger's Disease, Maladie de Roger Common
Ventricle Cor Triloculare Biatriatum }
$Volume{}
$Log{}
Copyright (C) 1986 National Organization for Rare Disorders, Inc.
169:
Ventricular Septal Defects
** IMPORTANT **
It is possible that the main title of the article (Ventricular Septal
Defects) is not the name you expected. Please check the SYNONYMS listing to
find the alternate names and disorder subdivisions covered by this article.
Synonyms
DISORDER SUBDIVISIONS
Roger's Disease, also known as Maladie de Roger
Common Ventricle, also known as Cor Triloculare Biatriatum
General Discussion
** REMINDER **
The information contained in the Rare Disease Database is provided for
educational purposes only. It should not be used for diagnostic or treatment
purposes. If you wish to obtain more information about this disorder, please
contact your personal physician and/or the agencies listed in the "Resources"
section of this report.
Ventricular Septal Defects are a relatively common form of congenital
heart disease. The septum separating the two ventricles is incompletely
formed before birth. This can result in inefficient distribution of oxygen
to the various tissues of the body and various degrees of congestive heart
failure, manifested by edema, difficulty breathing, and rapid heart beat.
The size of the opening in the septum determines the clinical severity of the
disorder. Some patients with large defects do not survive infancy. In
addition, the lungs can be permanently damaged by the abnormal pulmonary
blood pressures generated. Occasionally, ventricular septal defects may close
spontaneously or become relatively less significant as the heart grows along
with the rest of the body. The patterns and quality of the sounds of the
beating heart, electrocardiographic (EKG) and echocardiographic findings, and
information from cardiac catheterization help determine the exact anatomic
defect and differentiate ventricular septal defects from other heart
conditions with similar symptoms. Heart sounds evaluation and the EKG are
the most commonly performed initial investigations for these purposes.
Symptoms
First, a short review of the structure and function of the normal heart. The
human heart has 4 chambers, that is, two atria and two ventricles.
Deoxygenated blood enters the right atrium from the systemic veins (i.e., the
veins draining all the body organs and tissues except the lungs). It is
pumped from the right atrium to the right ventricle and from the right
ventricle to the pulmonary artery. The pulmonary artery carries the blood to
the lungs, where it is saturated with oxygen. From the lungs, the blood
passes through the pulmonary veins to the left atrium, and thence into the
left ventricle, the most muscular of the four chambers of the heart. The
contraction of the left ventricle forces the blood back into the systemic
circulation where it supplies oxygen to the various body tissues. Blood then
collects in veins which eventually come together and drain again into the
right atrium. The two atria are separated from each other by a relatively
thin membrane known as the atrial septum. The ventricular septum separates
the right and the left ventricles.
In ventricular septal defects the membrane separating the ventricles
(septum) is incomplete. A small defect, causing minor or no symptoms, is
known as Roger's Disease. Sometimes the hole is very high in the ventricular
septum, adjacent to the atria, so the communication is between the left
ventricle and the right atrium; symptoms resemble those of pure ventricular
septal defects. A very large opening causes severe symptoms. If the septum
is entirely absent, the two ventricles constitute a single chamber. This
condition is known as Common Ventricle or Cor Triloculorum Biatriatum.
Septal defects allow deoxygenated blood from the right ventricle to mix
with freshly oxygenated blood from the left ventricle. Although the blood
tends to move from left to right in ventricular defects, maintaining a fairly
high average saturation in the systemic circulation, some decrease in the
overall availability of oxygen to the body tissues usually occurs. More
significantly, however, large defects create abnormal pressure conditions in
the pulmonary and systemic circulation. As hypertension (high blood
pressure) gradually develops in the lungs, the pulmonary vasculature is
permanently damaged, often by the time the patient reaches adolescence.
Small defects may cause no symptoms, or mild signs of congestive heart
failure such as slight generalized edema and breathing difficulty after
exercise or with fatigue. In infants, poor feeding due to fatigue, cold
grayish extremities, and rapid shallow breathing can indicate heart disease.
In infants and children, large defects can cause growth retardation and
potentially fatal heart failure. In adults, difficulty breathing after
physical exertion, chest pain, episodes of fainting, coughing up of blood,
and signs of extremely low oxygen saturation of the blood in the tissues,
including bluish skin coloration (cyanosis), clubbing of the fingers, and a
high concentration of red blood cells may occur.
Ventricular septal defects of moderate size are characterized by
enlargement of the heart, milder and less progressive symptoms, and
characteristic heart sounds and EKG.
When there is a common ventricle, symptoms resemble those of large septal
defects. The systemic and pulmonary circulation always mixes, although
cyanosis and similar signs of poor oxygen delivery may not be as severe as
expected. Pulmonary hypertension and its consequences are likely to develop.
Heart defects seem to predispose patients to respiratory infections and
bacterial infection of the inner lining of the heart (bacterial
endocarditis). Bacterial endocarditis seems to occur more often with small or
moderate sized septal defects. These infections should be avoided,
particularly since resulting damage is likely to worsen the patient's
condition.
Causes
The causes of the arrest in embryonic development resulting in congenital
heart disease are poorly understood. Only about 10% of the cases appear to
be hereditary. Maternal rubella (measles), alcoholism or diabetes have been
associated with some heart defects. Ostium primum defects often occur in
individuals with Down's Syndrome, and certain other chromosomal
abnormalities.
Affected Population
About 1% of live births have some kind of congenital heart defect; of these,
about 30% have ventricular septal defects. Males are affected more often
than females.
Related Disorders
Other congenital heart defects include atrial septal defects, valve defects
of various kinds, malformations of the large vessels entering and leaving the
heart, and anomalous positions of the heart in the chest. Tetralogy of
Fallot consists of four heart abnormalities that occur together, and include
a large ventricular septal defect.
Therapies: Standard
The definitive treatment for ventricular septal defects is surgical. The
hole in the septum is either sutured shut or patched with a graft. The
success rate is quite high. Surgery is indicated when significant shunting
appears, especially when resistance to the entry of blood into the lungs is
high. It is most successful in patients between the ages of 3 and 6 years.
Presurgical, palliative treatment includes medication such as digitalis
to treat arrhythmias, excessively rapid heart beat, and stop heart failure.
Sodium restriction, diuretics and rest are also effective in treating
congestive heart failure. Respiratory infections are treated vigorously, and
antibiotics are given prophylactically with such procedures as tooth
extractions to reduce the risk of developing bacterial endocarditis.
Therapies: Investigational
This disease entry is based upon medical information available through May
1990. Since NORD's resources are limited, it is not possible to keep every
entry in the Rare Disease Database completely current and accurate. Please
check with the agencies listed in the Resources section for the most current
information about this disorder.
Resources
For more information on Ventricular Septal Defects, please contact:
National Organization for Rare Disorders (NORD)
P.O. Box 8923
New Fairfield, CT 06812-1783
(203) 746-6518
American Heart Association
7320 Greenville Avenue
Dallas, TX 75231
(214) 750-5300
NIH/National Heart, Lung, and Blood Institute (NHLBI)
9000 Rockville Pike
Bethesda, MD 20892
(301) 496-4236
For information on genetics and genetic counseling referrals, please
contact:
March of Dimes Birth Defects Foundation
1275 Mamaroneck Avenue
White Plains, NY 10605
(914) 428-7100
Alliance of Genetic Support Groups
35 Wisconsin Circle, Suite 440
Chevy Chase, MD 20815
(800) 336-GENE
(301) 652-5553
References
Petersdorf, Robert G., et al, editors, Harrison's Principles of Internal
Medicine, tenth edition. New York: McGraw-Hill 1983, Pp. 1383-96.
THE MERCK MANUAL, 15th ed., Robert Berkow, M.D., ed in chief, published
by Merck, Sharp & Dohme Research Labs, Rahway, NJ, 1987. Pp. 1926, 358.
THE CECIL TEXTBOOK OF MEDICINE, 18th Ed.: James B. Wyngaarden and Lloyd
H. Smith, Jr., Eds; W.B. Saunders Co. 1988. Pp. 306.