Tricuspid atresia
Encyclopedia
Tricuspid atresia is a form of congenital heart disease whereby there is a complete absence of the tricuspid valve
. Therefore, there is an absence of right atrioventricular connection. This leads to a hypoplastic (undersized) or absent right ventricle
.
This defect is contracted during prenatal development, when the heart does not finish developing. It causes the heart to be unable to properly oxygenate the rest of the blood in the body. Because of this, the body does not have enough oxygen to live, and steps must be taken to keep the child alive.
Because of the lack of an A-V connection, an atrial septal defect
(ASD) must be present to maintain blood flow. Also, since there is a lack of a right ventricle there must be a way to pump blood into the pulmonary arteries, and this is accomplished by a ventricular septal defect
(VSD).
Blood is mixed in the left atrium
. Because the only way the pulmonary circulation receives blood is through the VSD, a patent ductus arteriosus
usually also persists to increase pulmonary flow.
Tricuspid valve
The tricuspid valve, or right atrioventricular valve, is on the right dorsal side of the mammalian heart, between the right atrium and the right ventricle. The normal tricuspid valve usually has three leaflets and three papillary muscles. They are connected to the papillary muscles by the chordae...
. Therefore, there is an absence of right atrioventricular connection. This leads to a hypoplastic (undersized) or absent right ventricle
Right ventricle
The right ventricle is one of four chambers in the human heart. It receives deoxygenated blood from the right atrium via the tricuspid valve, and pumps it into the pulmonary artery via the pulmonary valve and pulmonary trunk....
.
This defect is contracted during prenatal development, when the heart does not finish developing. It causes the heart to be unable to properly oxygenate the rest of the blood in the body. Because of this, the body does not have enough oxygen to live, and steps must be taken to keep the child alive.
Because of the lack of an A-V connection, an atrial septal defect
Atrial septal defect
Atrial septal defect is a form of congenital heart defect that enables blood flow between the left and right atria via the interatrial septum. The interatrial septum is the tissue that divides the right and left atria...
(ASD) must be present to maintain blood flow. Also, since there is a lack of a right ventricle there must be a way to pump blood into the pulmonary arteries, and this is accomplished by a ventricular septal defect
Ventricular septal defect
A ventricular septal defect is a defect in the ventricular septum, the wall dividing the left and right ventricles of the heart.The ventricular septum consists of an inferior muscular and superior membranous portion and is extensively innervated with conducting cardiomyocytes.The membranous...
(VSD).
Blood is mixed in the left atrium
Left atrium
The left atrium is one of the four chambers in the human heart. It receives oxygenated blood from the pulmonary veins, and pumps it into the left ventricle, via the mitral valve.-Foramen ovale:...
. Because the only way the pulmonary circulation receives blood is through the VSD, a patent ductus arteriosus
Patent ductus arteriosus
Patent ductus arteriosus is a congenital disorder in the heart wherein a neonate's ductus arteriosus fails to close after birth. Early symptoms are uncommon, but in the first year of life include increased work of breathing and poor weight gain...
usually also persists to increase pulmonary flow.
Clinical manifestations
- progressive cyanosisCyanosisCyanosis is the appearance of a blue or purple coloration of the skin or mucous membranes due to the tissues near the skin surface being low on oxygen. The onset of cyanosis is 2.5 g/dL of deoxyhemoglobin. The bluish color is more readily apparent in those with high hemoglobin counts than it is...
- poor feeding
- tachypneaTachypneaTachypnea means rapid breathing. Any rate between 12-20 breaths per minute is normal. Tachypnea is a respiration rate greater than 20 breaths per minute. - Distinction from other breathing terms :...
over the first 2 weeks of life - holosystolic murmurHeart murmurMurmurs are extra heart sounds that are produced as a result of turbulent blood flow that is sufficient to produce audible noise. Most murmurs can only be heard with the assistance of a stethoscope ....
due to the VSD - left axis deviationLeft axis deviationLeft axis deviation is a condition whereby the mean electrical axis of ventricular contraction of the heart lies in a frontal plane direction between -30° and -90°...
on electrocardiography and left ventricular hypertrophyLeft ventricular hypertrophyLeft ventricular hypertrophy is the thickening of the myocardium of the left ventricle of the heart.-Causes:While ventricular hypertrophy occurs naturally as a reaction to aerobic exercise and strength training, it is most frequently referred to as a pathological reaction to cardiovascular...
(since it must pump blood to both the pulmonary and systemic systems) - normal heart size
Treatment
- PGE1 to maintain patent ductus arteriosusPatent ductus arteriosusPatent ductus arteriosus is a congenital disorder in the heart wherein a neonate's ductus arteriosus fails to close after birth. Early symptoms are uncommon, but in the first year of life include increased work of breathing and poor weight gain...
- modified Blalock-Taussig shunt to maintain pulmonary blood flow by placing a Gore-TexGore-TexGore-Tex is a waterproof/breathable fabric, and a registered trademark of W. L. Gore and Associates. It was co-invented by Wilbert L. Gore, Rowena Taylor, and Gore's son, Robert W. Gore. Robert Gore was granted on April 27, 1976, for a porous form of polytetrafluoroethylene with a...
conduit between the subclavian arterySubclavian arteryIn human anatomy, the subclavian arteries are two major arteries of the upper thorax , below the clavicle . They receive blood from the top of the aorta...
and the pulmonary arteryPulmonary arteryThe pulmonary arteries carry deoxygenated blood from the heart to the lungs. They are the only arteries that carry deoxygenated blood....
. - cavopulmonary anastomosis (hemi-Fontan or bidirectional Glenn) to provide stable pulmonary flow
- Fontan procedureFontan procedureThe Fontan procedure, or Fontan/Kreutzer procedure, is a palliative surgical procedure used in children with complex congenital heart defects. It involves diverting the venous blood from the right atrium to the pulmonary arteries without passing through the morphologic pulmonary ventricle...
to redirect inferior vena cavaInferior vena cavaThe inferior vena cava , also known as the posterior vena cava, is the large vein that carries de-oxygenated blood from the lower half of the body into the right atrium of the heart....
and hepatic veinHepatic veinIn human anatomy, the hepatic veins are the blood vessels that drain de-oxygenated blood from the liver and blood cleaned by the liver into the inferior vena cava....
flow into the pulmonary circulation
External links
- Tricuspid Atresia information from Seattle Children's Hospital Heart Center