Tricuspid Atresia
Overview
Tricuspid atresia (TA) is a heart defect present at birth (congenital). It occurs
when
the tricuspid valve doesn’t form, or only partly forms. Normally the tricuspid valve
is
located between the right upper chamber (atrium) and the right lower chamber (ventricle)
of the heart. Instead of a valve, a piece of tissue forms that restricts blood flow
between the right atrium and right ventricle. The defect keeps low oxygenated blood
from
flowing normally into the right atrium to the right ventricle, and to the lungs where
the blood becomes oxygenated. With TA, there is mixing of low oxygenated blood with
oxygenated blood. This means not enough oxygen in the blood is carried to the body.
This
may cause a blue coloring of the skin or lips.
In
tricuspid atresia, the following occurs:
- The
tricuspid valve doesn't form correctly or at all.
- The
right ventricle is often smaller than normal.
- There is
an opening between the two atria (atrial septal defect). This is often an open
(patent) foramen ovale. The foramen ovale is a normal part of fetal circulation that
usually closes shortly after birth.
- There
is an opening between the ventricles (ventricular septal defect).
- An open
(patent) ductus arteriosus lets blood flow from the aorta to the pulmonary artery.
This lets blood flow to the lungs for oxygen. The ductus arteriosus is a normal part
of fetal circulation. It usually closes shortly after birth.
- Other
heart defects may also be present. These may include transposition of the great
vessels, pulmonary stenosis, or pulmonary atresia.
Causes
A
baby's heart develops during the first 8 weeks of pregnancy. In TA, the tricuspid
valve
doesn't form as it should. Development of the ventricles is helped by blood flowing
through them. Because blood doesn't pass through the tricuspid valve, the right
ventricle remains small.
Some
congenital heart defects may be passed down through families (genetic defects). Most
of
the time, there is no known cause for TA.
Symptoms
Symptoms of TA occur shortly after birth. Common symptoms may include:
- Blue
color of the skin, lips, and nail beds (cyanosis)
- Fast
breathing
- Trouble
breathing
- Fast
heart rate
- Poor
feeding
The
symptoms of TA may look like other health conditions. Have your child see their
healthcare provider for a diagnosis.
Diagnosis
TA
may be diagnosed with a prenatal ultrasound exam. Otherwise, symptoms occur shortly
after birth. A pediatric cardiologist or a neonatologist will help care for your child.
These are healthcare providers with special training to treat problems in children.
One
or more healthcare providers will examine your baby. They will listen to your baby's
heart and lungs with a stethoscope and note any abnormal heart sound (heart
murmur).
Testing for congenital heart disease may include:
-
Pulse
oximetry.
A simple test that uses a small probe to check the amount of oxygen
in the blood.
-
Lab tests.
Blood and urine samples will be checked.
-
Chest
X-ray.
A chest X-ray may show changes often seen with TA.
-
Electrocardiogram (ECG). An ECG records the electrical activity of the
heart. It shows abnormal rhythms and finds heart muscle stress.
-
Echocardiogram (echo). An echo uses sound waves to make a moving picture of
the heart and heart valves. The diagnosis of TA will be made based on finding the
abnormal heart structures.
-
Heart cath (cardiac catheterization). This
procedure gives very detailed information about the structures inside the heart. Your
child will be given medicine to relax (sedation). Then a thin, flexible tube
(catheter) is put into a blood vessel in your child's groin. Under continuous X-ray
(or fluoroscopy), the catheter is guided to the heart. Blood pressure and oxygen
measurements are taken in the heart chambers, the pulmonary artery, and the aorta.
Contrast dye is also injected to more clearly see the structures inside the heart. A
heart cath is not often done to diagnose this condition. But it may be done before
surgery and in the early treatment of the defect.
Treatment
Your
child will most likely be in the intensive care unit (ICU). Early medical treatment
may
include:
- Supplemental oxygen or possibly a mechanical breathing machine (ventilator) to help
with breathing
- Medicines may be given to help the heart and lungs work better. Prostaglandin E1 may
be given to keep the ductus arteriosus open.
Other early treatment may include:
-
Cardiac
cath.
In some cases, cardiac cath may be used in the early period. If
pulmonary stenosis is present, a catheter with a balloon at the tip can be inflated
to widen the valve and let enough blood flow through.
-
Balloon
atrial septostomy.
A special catheter with a balloon in the tip is used to
create or enlarge an opening in the wall between the left and right atria (atrial
septum). This helps with blood flow from the right side of the heart to the left side
of the heart.
Three surgeries, in stages, may be done. They include:
-
Blalock-Taussig shunt. This surgery is done on newborns. It varies,
depending on the exact defect your child has. A connection (shunt) is created to let
blood from the aorta reach the lungs and pick up oxygen.
-
Glenn shunt.
This surgery may be done on babies ages 2 to 6 months. A new connection (shunt)
replaces the first shunt. This shunt connects the large blood vessel from the top
of
the body to the heart (superior vena cava) to the pulmonary artery. This allows blood
to get to the lungs for oxygen.
-
Fontan
procedure.
This surgery may be done from ages 2 to 3. A second connection
(shunt) is made. It allows blood from the large blood vessel from the lower part of
the body to the heart to flow to the pulmonary artery. This surgery varies depending
on the exact defect, as well as other factors.
Complications
Complications of TA may include:
- Not enough oxygen getting to the body's tissues (hypoxemia)
- Enlarged right atrium
- Heart
rhythm problems (arrhythmias)
- Less
ability to exercise
- Heart
failure
- Poor growth and development
- Death
Living with
Your
child may need a series of repair procedures.
Before your child comes home, the nursing staff will explain medicines and treatments.
For instance, your child may need special formula and supplemental feedings to help
them
grow. The staff will also help to arrange home healthcare, if needed. You may get other
instructions from your child's heart care team and the hospital staff.
Babies will have a blue color to their skin (cyanosis) after the first two
surgeries, or until the final Fontan procedure is done. Your child may grow and develop
slowly because of decreased oxygen in the blood. After the Fontan procedure, when
oxygen
levels get better, you will likely see large improvements in your child's growth and
development.
Your
child will need to be seen often by a pediatric cardiologist. The cardiologist may
advise:
- Your
child should get all advised vaccines.
- Your
child will likely need antibiotics before some types of surgery or dental
procedures.
- Your
child may not be able to take part in some sports.
- As your
child grows and matures, they will need to work with a cardiologist and other
healthcare providers to plan pregnancy or surgeries.
Regular follow-up care at a center offering pediatric or adult congenital cardiac
care
should continue throughout life.
Talk
with your child's cardiologist about the specific outlook for your child.
When to Call a Healthcare Provider
Call your child's healthcare provider
if your child's normal symptoms become worse or if new symptoms appear.
Key Points
- Tricuspid atresia (TA) occurs when the tricuspid valve does not develop correctly.
This prevents blood flow from the right atrium to the right ventricle.
- TA may
be identified during a prenatal ultrasound or shortly after birth when the baby has
symptoms like turning blue (cyanotic).
- Your
child will stay in the intensive care unit (ICU).
- Your
child will need medicines and a series of surgeries to allow oxygen-rich (red) blood
to be pumped to the body.
- Your
child will need to be followed by a specialist in congenital heart
conditions throughout their life.
Next Steps
Tips
to help you get the most from a visit to your child’s healthcare provider:
- Know
the reason for the visit and what you want to happen.
- Before
your visit, write down questions you want answered.
- At the
visit, write down the name of a new diagnosis, and any new medicines, treatments,
or
tests. Also write down any new instructions your healthcare provider gives you for
your child.
- Know why
a new medicine or treatment is prescribed and how it will help your child. Also know
what the side effects are.
- Ask if
your child’s condition can be treated in other ways.
- Know why
a test or procedure is recommended and what the results could mean.
- Know
what to expect if your child does not take the medicine or have the test or
procedure.
- If your
child has a follow-up appointment, write down the date, time, and purpose for that
visit.
- Know
how you can contact your child’s healthcare provider after office hours. This is
important if your child becomes ill and you have questions or need advice.