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OSTIUM SECUNDUM ATRIAL SEPTAL DEFECT

OSTIUM SECUNDUM ATRIAL SEPTAL DEFECT (see also [For More Information] and Figs. 3–80 Figs. 3–80 , and 29–11 29–11 ). This anomaly is among the most common congenital cardiac malformations in unoperated adults and is by far the most common shunt lesion.25–27 Although life expectancy is not normal, survival into adulthood is the rule.5 Ostium secundum atrial septal defects are sporadically found in patients beyond age 70 years and occasionally in patients in their 80’s or 90’s.26–28 One of the author’s patients died at age 87 (Fig. 30–5 Fig. 30–5 ), and another lived relatively comfortably until 3 months before his 95th birthday.29

Almost all patients who survive beyond the sixth decade are symptomatic. Death may be unrelated to the malformation, but when a relationship exists, cardiac failure is the most common cause of death. Older patients deteriorate chiefly on three counts5: (1) A decrease in left ventricular distensibility (acquired coronary artery disease, systemic hypertension) augments the left-to-right shunt; (2) atrial tachyarrhythmias, especially fibrillation, less commonly flutter or atrial tachycardia, increase in frequency after the fourth decade and serve to precipitate right ventricular failure; (3) the majority of symptomatic adults beyond age 40 have mild to moderate pulmonary hypertension despite the presence of a persistent, large left-to-right shunt, so the aging right ventricle is doubly beset by both pressure and volume overload.

The incidence, extent, and degree of associated mitral valve disease increase with age and the disease is characterized morphologically by thick, fibrotic leaflets and short, fibrotic chordae tendineae.30,31 These mitral valve abnormalities have been attributed to abnormal cusp movement (trauma) caused by the effects of left ventricular cavity deformity (abnormal position and motion of the ventricular septum in response to volume overload of the right ventricle).32,33 The abnormalities are believed to be the basis for the mitral regurgitation that tends to develop with age in about 15 per cent of patients.29–31

PATENT DUCTUS ARTERIOSUS

PATENT DUCTUS ARTERIOSUS (see also [For More Information] and Fig. 29–19 Fig. 29–19 ). A large ductus is a relatively common cause of congestive heart failure in term infants, but after the first year of life, most patients with patent ductus arteriosus are asymptomatic.34 In the second decade, the risk of infective endarteritis exceeds the risk of heart failure.34 Beginning with the third decade (occasionally earlier), more patients with significant left-to-right shunts develop heart failure,35 whereas those with small shunts remain asymptomatic. One of the author’s patients was an 84-year-old woman with a moderately restrictive patent ductus, atrial fibrillation, and congestive heart failure (Fig. 30–6 Fig. 30–6 ), and there is one report of survival to age 90.36 A significant cumulative risk of infective endarteritis exists, especially if the ductus is restrictive. Patients with nonrestrictive patent ductus arteriosus seldom reach adulthood unless a rise in pulmonary vascular resistance relieves the left ventricle of excessive volume overload.37 Survival to adulthood is then the rule, with differential cyanosis a distinctive feature of the reversed shunt.5



Uncommon Defects in Which Unoperated Adult Survival is Expected

Uncommon Defects in Which Unoperated Adult Survival is Expected

SITUS INVERSUS WITH DEXTROCARDIA

SITUS INVERSUS WITH DEXTROCARDIA (see also [For More Information] ). This cardiac malposition usually occurs with an otherwise structurally and functionally normal heart.5 Symptoms related to acquired cardiac or noncardiac disease may lead to the discovery of the hitherto unsuspected malposition. If angina pectoris or myocardial infarction occurs with complete situs inversus, the pain is located in the right anterior chest with radiation to the right shoulder and right arm.38 The pain of appendicitis is referred to the left lower quadrant, and the pain of biliary colic presents in the left upper quadrant, owing to the mirror image positions of abdominal viscera. The cardiac malposition is occasionally associated with sinusitis and bronchiectasis—Kartagener’s triad.5 Symptoms of bronchiectasis usually develop in early adulthood and may prompt investigations that lead to the discovery of the malposition. Situs inversus is common in men with infertility secondary to sperm immotility,39 an observation that led to identification of a generalized disorder of ciliary motility in Kartagener’s triad.40 When situs inversus with dextrocardia coexists with congenital malformations of the heart, survival is determined by the associated anomalies.5


Date: 2014-12-21; view: 1110


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