anomaly is due to a defect in the tricuspid valve (TV) with
the septal and posterior leaflets displaced down into the right
ventricle, while the anterior leaflet is malformed and abnormally
attached to the RV free wall (see figure 23D). This valve often
allows blood to regurgitate from the small RV back into the
large RA. Eighty percent of these patients have ASD's through
which right-to-left shunting of blood may occur with cyanosis.
Such patients are at risk for a paradoxical embolus (blood clot)
from the RA through the LA to the brain with abscess(instead
of the normal route of an embolus from the legs to the lungs
via the right ventricle through the pulmonary valve)and sudden
is usually a heart murmur. EKG abnormalities are often present
including WPW syndrome,an atrial tachycardia or rapid heart
beat(see figure 1, 2, 3A, 3B). Twenty percent have an accessory
electrical pathway between the atrium and ventricle (see figure
1) to account for the cardiac arrhythmias.
can define the abnormalities, and a color Doppler imaging study
can determine the presence and size of interatrial shunting.
involves prevention of complications, such as heart infection,
prevented with antibiotic prophylaxis. Heart failure is treated
with diuretics (diuril, lasix, etc) (to eliminate fluid) and
digoxin (a heart drug to improve heart muscle contractions).
Arrhythmias may be treated with medication or catheter ablation
(see figure 3b, 11).
or replacement of TV in conjunction with closure of the interatrial
communication is recommended in older patients with severe symptoms
despite medical therapy and heart enlargement.