tricuspid atresia

atresia /atre·sia/ (ah-tre´zhah) congenital absence or closure of a normal body opening or tubular structure.atret´ic

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anal atresia , atresia a´ni imperforate anus.

aortic atresia  congenital absence of the aortic orifice.

biliary atresia  obliteration or hypoplasia of part of the bile ducts due to arrested fetal development, causing persistent jaundice and liver damage ranging from biliary stasis to biliary cirrhosis, with splenomegaly as portal hypertension progresses.

follicular atresia  degeneration and resorption of an ovarian follicle before it reaches maturity and ruptures.

laryngeal atresia  congenital lack of the normal opening into the larynx.

mitral atresia  congenital obliteration of the mitral orifice, often associated with hypoplastic left heart syndrome or transposition on great vessels.

prepyloric atresia  pyloric atresia; congenital membranous obstruction of the gastric outlet, with vomiting of gastric contents only.

pulmonary atresia  congenital severe narrowing or obstruction of the pulmonary orifice, with cardiomegaly, reduced pulmonary vascularity, and right ventricular atrophy. It is usually associated with tetralogy of Fallot, transposition of great vessels, or other cardiovascular anomalies.

pyloric atresia  prepyloric a.

tricuspid atresia  congenital absence of the tricuspid orifice, circulation being made possible by the presence of an atrial septal defect.

Tricuspid atresia, here displaying a ventricular septal defect and normally related great arteries, the arrows showing the altered flow of blood through the heart.

urethral atresia  congenital imperforation of the urethra.

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tricuspid atresia

n.

The congenital absence of the normal tricuspid orifice.

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tricuspid atresia,

a congenital cardiac anomaly characterized by the absence of the tricuspid valve so that there is no opening between the right atrium and right ventricle. Other cardiac defects, such as atrial and ventricular septal defects, are usually present, allowing some shunting of blood into the lungs. Clinical manifestations include severe cyanosis, dyspnea, anoxia, and signs of right-sided heart failure. Definitive diagnosis is made by cardiac catheterization, although radiographic studies usually reveal a small, underdeveloped right ventricle and large atria, giving the heart a round shape, and decreased pulmonary vascularity. Immediate palliative treatment includes pulmonary artery anastomoses to increase blood flow to the lungs and atrial septostomy if the atrial septal defect is small. Total corrective surgery has been successful in a limited number of older children.

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atresia

congenital absence or closure of a normal body opening or tubular structure.

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anal atresia, atresia ani

see anal atresia.

aortic atresia

absence of the opening from the left ventricle of the heart into the aorta.

aural atresia

absence of closure of the auditory canal.

biliary atresia

congenital obliteration or hypoplasia of one or more components of the bile ducts, resulting in persistent jaundice and liver damage.

choanal atresia

see imperforate buccopharyngeal membrane.

follicular atresia, atresia folliculi

premature degeneration and resorption of a graafian follicle of the ovary. It may be postovulatory or preovulatory atresia. It is a normal occurrence when several ova mature together. Abnormal atresia may be a cause of anestrus.

ileal atresia, atresia ilei

the congenital obstruction in calves may cause sufficient abdominal distention to result in dystocia.

inherited alimentary tract segmental atresia

occurs in cattle and horses. A variety of segments are involved, including ileum, colon, rectum and anus.

jejunal atresia, atresia jejuni

resembles ileal atresia clinically.

lacrimal puncta atresia

atresia of the lacrimal puncta causing tearing from birth.

mesonephric duct atresia

causes stenosis or aplasia of epididymis or ductus deferens.

nasolacrimal duct atresia

atresia of the nasolacrimal duct causing tearing from birth.

paramesonephric duct atresia

causes uterus unicornis or duplex uterus or segmental aplasia of a uterine horn or tube.

rectal atresia, atresia recti

congenital absence of luminal development leading to abdominal distention after birth. There is obvious absence of feces and staining and inability to pass a sound.

salivary duct atresia

congenital atresia causes distention of the gland followed by atrophy.

tracheal atresia

common in English bulldogs; may be segmental or affect the entire length of the tube.

tricuspid atresia

absence of the opening between the right atrium and right ventricle, circulation being made possible by an atrial septal defect.

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tricuspid atresia

Cardiology A rare congenital heart disease characterized by obstruction of blood flow from the right atrium to the right ventricle, by an absent or abnormally developed tricuspid valve, which compromises pulmonary blood flow; to maintain pulmonary blood flow, blood from the right atrium flows through the foramen ovale into the left atrium, then the left ventricle, then part of the blood flows directly into the right ventricle through a patent VSD or out the aorta via PDA allowing part of the aortic blood flow to flow into the pulmonary artery; this supplies the lungs with some, less than optimal, blood flow; it also puts a strain on the left ventricle which must pump both systemic and pulmonary blood Clinical Cyanosis, limited exercise tolerance, SOB. See Patent ductus arteriosus, Ventricular septal defect.