Definition Atrial isomerism is a condition in which the right-sided and left-sided atria, normally morphologically different, are morphologically similar. 1 Thus, left atrial isomerism and right atrial isomerism can occur. Atrial isomerism is a specific phenotypic feature highly associated with generalized somatic laterality disorders characterized by abnormal arrangement of thoracic and abdominal viscera, including important structural cardiovascular anomalies. The terms situs ambiguus and heterotaxy are used…

Definition Anatomically corrected malposition is an anomaly in the position of the great arteries but not in cardiac connections. Thus, there is atrioventricular (AV) and ventriculoarterial (VA) concordant connection as in the normal heart, but the aortic origin lies to the left and usually anterior to the pulmonary trunk origin when there is situs solitus (Van Praagh's S,D,L; see “Symbolic Convention of Van Praagh” in Chapter…

Definition Double inlet ventricle is a congenital cardiac malformation in which both atria connect to only one ventricular chamber by either two separate atrioventricular (AV) valves or a common AV valve. Closely related to double inlet ventricle are cardiac malformations in which both atria connect to only one ventricular chamber because of atresia of one AV valve that is imperforate or absent. As a group, double…

Section I Congenitally Corrected Transposition of the Great Arteries Definition Congenitally corrected transposition of the great arteries is a congenital cardiac anomaly with ventriculoarterial discordant connection (transposition of the great arteries) and atrioventricular (AV) discordant connection, the right atrium connecting to left ventricle and left atrium connecting to right ventricle. 1 Circulatory pathways are therefore in series. The condition occurs in atrial situs solitus and atrial situs…

Definition Double outlet left ventricle (DOLV) is a cardiac anomaly in which both great arteries arise from the left ventricle (LV). 1 The great arteries are assigned to one or the other ventricle by the rules described under Definition in Chapter 53 . 1 The adjectives left and right used to modify atrium or ventricle mean morphologically left and morphologically right. Position of the chamber is…

Definition Double outlet right ventricle (DORV) is a congenital cardiac anomaly in which both great arteries arise wholly or in large part from the right ventricle. 1 It is a type of ventriculoarterial connection (see “Cardiac Connections” under Terminology and Classification of Heart Disease in Chapter 1 ). 1 The adjectives left and right used to modify atrium or ventricle mean morphologically left and right, respectively.…

Definition Complete transposition of the great arteries (TGA) is a congenital cardiac anomaly in which the aorta arises entirely or largely from the right ventricle (RV) and in which the pulmonary trunk arises entirely or largely from the left ventricle (LV), known as ventriculoarterial discordant connection . 1 Although the phrase complete transposition of the great arteries may properly be applied whenever this situation exists, this…

Section I Vascular Ring Definition Vascular ring is a congenital anomaly in which the aortic arch and its branches completely or incompletely encircle and compress the trachea or esophagus or both. Historical Note Double aortic arch was apparently first described by Hommel in 1737 (cited by Turner) and a century later by Von Siebold. Wolman is credited with describing the syndrome of tracheal and esophageal compression…

Definition Congenital mitral valve disease is a developmental malformation of one or more of the components of the mitral valve apparatus, including that portion of left atrial wall immediately adjacent to the mitral anulus that produces stenosis or regurgitation or, occasionally, a combined lesion. It often coexists with other cardiac anomalies, particularly those involving the left-sided cardiac chambers and aorta. Left atrioventricular valve (AV) anomalies associated…

Definition Hypoplastic left heart physiology is defined as inability of the left heart to sustain adequate cardiac output following birth because of underdevelopment of one or more left heart structures despite surgical or medical intervention. Box 49-1 emphasizes four important implications of this definition. Box 49-1 Hypoplastic Left Heart Physiology 1 The term left heart refers to the morphologic composite or unit that includes left atrium,…

Section I Coarctation of the Aorta Definition Coarctation of the aorta is a congenital narrowing of the upper descending thoracic aorta adjacent to the site of attachment of the ductus arteriosus. The aortic lumen may be atretic in the most severe form of this defect, but aortic walls above and below the atresia are in continuity, as distinguished from aortic arch interruption, in which a short…

Congenital aortic stenosis is a cardiac anomaly in which narrowing at valvar, subvalvar, supravalvar, or combined (multiple) levels results in a systolic pressure gradient between the inflow portion of the left ventricle (LV) and the aorta beyond the obstruction. A spectrum of defects involves the aortic root, with some overlap of abnormalities. Congenital aortic stenosis in neonates and infants may be part of the constellation of…

Introduction Congenital anomalies of the coronary arteries represent a varied group of lesions. Taken together, they are relatively common, seen in 1% to 5% of the population, depending on the method of detection. Many lesions are incidental findings with little or no consequences, but approximately 20% have the potential to cause coronary ischemia and its sequelae. Box 46-1 presents a useful classification of all congenital coronary…

Definition Anomalous origin of a pulmonary artery from the ascending aorta is a condition in which the right pulmonary artery (RPA) or rarely, the left pulmonary artery (LPA), arises from the ascending aorta in the presence of separate aortic and pulmonary valves and without interposition of ductal tissue. This condition is sometimes referred to as hemitruncus . Hemitruncus is also used to describe a subset of…

Definition Aortopulmonary window (APW) is a round, oval, or sometimes spiral opening between the ascending aorta and pulmonary trunk, occurring as a congenital anomaly in hearts with separate aortic and pulmonary valves. This malformation has also been termed aortic septal defect; aortopulmonary fistula, fenestration, or septal defect; and aorticopulmonary window, fistula, fenestration, or septal defect. Historical Note The first report of an APW was by Elliotson…

Definition Truncus arteriosus (persistent truncus arteriosus, truncus arteriosus communis, common aorticopulmonary trunk) is a congenital cardiovascular malformation in which one great artery arising from the base of the heart by way of a single semilunar (truncal) valve gives origin to the coronary, systemic, and one or two pulmonary arteries proximal to the origin of the brachiocephalic branches. It is one of several diagnoses within the phylum…

Definition Ebstein anomaly is a congenital defect of the tricuspid valve in which origins of the septal or posterior leaflets or both are displaced downward into the right ventricle, and the leaflets are variably deformed. Characteristically, the anterior leaflet is enlarged and “sail-like.” There is a wide spectrum of severity; in the mildest asymptomatic forms, the valve may appear normal at first sight, and classification as…

Section I Tricuspid Atresia and Single-Ventricle Physiology Definition Tricuspid Atresia Tricuspid atresia is a congenital cardiac malformation in which the right atrium, in the setting of ventricular D-loop, fails to open into a ventricle through an atrioventricular (AV) valve. Thus, there is univentricular AV connection consisting of a left-sided mitral valve between morphologically left atrium and left ventricle (LV). Atrial situs is almost invariably solitus (normal)…

Definition Pulmonary atresia and intact ventricular septum is a congenital malformation in which the pulmonary valve is atretic and no ventricular septal defect exists. It coexists with variable degrees of right ventricular (RV) and tricuspid valve hypoplasia, and variable degrees of coronary artery abnormalities. This chapter discusses this malformation in the setting of atrioventricular and ventriculoarterial concordant connections. Historical Note In 1839, Peacock collected records of…

Definition Pulmonary stenosis and intact ventricular septum is a form of right ventricular outflow tract obstruction in which the stenosis can be valvar, infundibular, or both. Isolated infundibular stenosis is unusual. This chapter concerns primarily valvar pulmonary stenosis, with or without infundibular stenosis. When neonates present with the most severe form of this defect, the term neonatal critical pulmonary stenosis is used. When patients present beyond…