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Congenital absence of the pericardium is an abnormality characterized by a spectrum of findings ranging from a small defect to complete absence of the pericardium.

The heart lies in the middle mediastinum within the pericardial sac. The pericardial sac is formed by two layers: the outer layer known as the fibrous pericardium and the inner layer known as the serous pericardium. The serous pericardium contains two layers: visceral and parietal. The inner visceral layer covers the surface of heart and base of the great vessels. At the level of the great vessels, it reflects and becomes the parietal layer, which lines the thick fibrous pericardium. The fibrous pericardium fuses with the base of the great vessels and the diaphragm and it is attached to the sternum by the sternopericardial ligament.

The classic lesions of tetralogy of Fallot (TOF) include pulmonary stenosis, ventricular septal defect (VSD), overriding aorta, and right ventricular hypertrophy. The hemodynamically significant lesions are the VSD and pulmonary stenosis that results in right ventricular outflow tract (RVOT) obstruction. Originally, a two-stage repair was performed for repair of TOF. First pulmonary blood flow was increased with systemic-to-pulmonary artery shunts (classic and modified Blalock–Taussig shunt, Waterston shunt, or Potts shunt) followed by a complete repair when the child was older. Complications associated with this strategy include pulmonary hypertension and congestive heart failure from the augmented pulmonary blood flow and stenosis of the pulmonary artery at the anastomotic site.

Hypoplastic left heart syndrome (HLHS) is characterized by hypoplasia of the left heart and varying degrees of hypoplasia or atresia of the aortic valve and ascending aorta. It is included in the spectrum of conditions that can result in a cardiac circulation with a functionally single ventricle. Left untreated, HLHS is invariably lethal. Advances in palliative surgical procedures (Norwood procedure, bidirectional cavopulmonary shunt, modified Fontan procedure) have increased the survival rate in children with HLHS.

Univentricular heart, also termed “functionally single ventricle” and “single ventricle,” refers to the congenital heart defects in which the heart functionally has only one pumping chamber. The unifying criteria to identify a univentricular heart is a main (dominant) ventricle with a malformed atrioventricular connection and a rudimentary (incomplete) ventricle, which lacks an inlet component or less commonly an outlet component [1–4]. A true single ventricle is exceedingly rare.

Arterial switch (Jatene) procedure, which was developed in the late 1970s, is currently the method of choice for treatment of transposition of the great arteries (TGA). It reestablishes the left ventricle as a systemic pump, avoiding systemic ventricular failure associated with the atrial switch operation. This procedure is indicated for patients with TGA with an intact ventricular septum or with a small ventricular septal defect (VSD). Patients with large nonrestrictive VSDs, left ventricular outflow obstruction, or increased pulmonary vascular resistance may not be candidates for the arterial switch procedure.

Aortic valve stenosis refers to a narrowing of the lumen of the aortic valve. It is the most common cardiac valvular condition requiring valve replacement. Congenital stenosis is the most common cause of aortic valve stenosis. It is usually associated with anomalous valves, most commonly the bicuspid aortic valve. The congenitally stenotic aortic valve also may be unicuspid (acommissural or unicommissural) or, rarely, congenitally quadricuspid/quadricommissural. A dysplastic tricuspid aortic valve can also develop stenosis (Fig. 13.1).

The Damus–Kaye–Stansel (DKS) operation is a palliative procedure for patients with a single functioning ventricle with an obstructed rudimentary outflow chamber. It is not used for treatment of hypoplastic left heart syndrome which is treated using the Norwood procedure. operation is used for in double-inlet left ventricle, tricuspid atresia with transposition of the great arteries (TGA), and a common atrioventricular canal with small left ventricular cavity.

Congenital pulmonary valve abnormalities encompass a spectrum of anomalies that result in right ventricular outflow tract (RVOT) obstruction. Based on the level of obstruction, there are three possible variants: (a) valvular, (b) subvalvular (infundibular stenosis), and (c) supravalvular.

Tetralogy of Fallot (TOF) is characterized by four constant features: right ventricular outflow tract (RVOT) obstruction, malalignment (perimembranous) ventricular septal defect (VSD), biventricular origin of the aorta (overriding aorta), and right ventricular hypertrophy [1].

The first attempt to repair a patient with transposition of the great arteries (TGA) was performed by Senning who successfully constructed an atrial baffle in 1958 [1]. The procedure employed an atrial baffle created from autologous tissue to redirect caval blood to the left atrium which emptied into the left ventricle which then pumped the deoxygenated blood to the lungs. Pulmonary venous blood was redirected to the morphologic right atrium and through the tricuspid valve into the right ventricle which then filled the aorta with oxygenated blood. Subsequently, in 1964, Mustard introduced an atrial switch procedure utilizing prosthetic patch material to create an intra-atrial baffle (Figs. 23.1 and 23.2) [2, 3]. See Fig. 19.22 for a diagram of the uncorrected circulation and the circulation after the atrial switch procedure which normalizes the blood flow circuit.

Ebstein anomaly is a myopathy of the right ventricle that results in variable degrees of failure of delamination of the valve leaflets, leading to tricuspid valve regurgitation and right ventricular dysfunction. The classic pathology is apical (downward) displacement of the tricuspid valve leaflets (most frequently septal followed by posterior and anterior leaflets) with abnormal adherence of the leaflets to the underlying myocardium.

The first surgical repair of aortic coarctation was performed in 1944 [1]. Since then three basic surgical methods have evolved for repair of classic short-segment aortic coarctation (CoAo): resection of the coarcted segment with end-to-end anastomosis (Fig. 32.1), subclavian flap aortoplasty (distal left subclavian artery used to augment aortic lumen at the coarctation site), and prosthetic patch aortoplasty (prosthetic patch inserted to widen the aortic lumen) [2]. The choice of procedure depends on the age of the patient, the type of associated malformations, and the morphology of the coarctation itself. Surgical treatment is preferred in neonates and infants. The other procedure types have been used in adults. Subclavian flap aortoplasty is no longer commonly performed because it requires sacrifice of the left subclavian artery which leads to arm claudication with exercise and diminished growth of the left arm [3].

Liquefactive necrosis within a large spheroid zone of mitral annular calcification (LNMAC) is an atypical but increasingly recognized variant of mitral annular calcification (MAC). Proposed MRI, echo, and CT imaging criteria for diagnosis of this unusual disease entity are discussed along with a review of the prognosis, histopathology, and management implications. A comprehensive ECHO, CT, and MRI imaging approach to diagnostic differentiation from other cardiac masses, allowing characterization of the differing components of this unusual lesion is emphasized. Differentiation from surrounding myocardium, and demonstration of peripheral ring type hyperenhancement, or hyperintense signal in the wall of this lesion, seen with specific inversion recovery MRI sequences is presented as a major diagnostic criterion. The relationship of these MRI image findings to underlying pathology is also discussed. An illustrative case vignette is provided for clinical reference.

The thoracic aorta extends from aortic annulus to the diaphragm and includes the ascending aorta, the aortic arch, and the descending thoracic aorta. The first 3 cm of the proximal aorta are intrapericardial. The thoracic aorta anatomy may be seen in Figs. 5.1–5.3.

When beginning proximally, the normal aortic arch gives rise to the right brachiocephalic artery, the left carotid artery, and, finally, the left subclavian artery. The brachiocephalic artery and the left carotid artery are more anterior on the arch. The right common carotid artery and right vertebral arteries arise from the right brachiocephalic artery. The right common carotid artery splits into the right internal and the right external carotid arteries. The left common carotid artery, arising directly from the aortic arch, gives rise to the left internal and the left external carotid artery. The carotid bulb (Fig. 5.4) refers to the region just before the bifurcation of the internal carotid artery. More distally on the arch, the left subclavian artery arises and gives off the left vertebral artery. Many normal variant arch anomalies can occur (Figs. 5.5–5.9).