(Case 1: Courtesy Saroja Bharati, MD, The Heart Institute for Children, Hope Children's Hospital, Palos Heights, IL.
Case 2: Courtesy Jeffrey E. Saffitz, MD, PhD, Department of Pathology and Immunology, Washington University School of Medicine, St. Louis, MO.)

This view is analogous to the conventional four-chamber view of the heart of a 10-year-old girl with complex congenital heart disease and chronic complete atrioventricular block who died suddenly at home. The malformations consist of

Indeterminate atrial and cardiac situs (pathologic diagnosis made in absence of abdominal organs to examine overall situs).

Common atrium with pulmonary venous return symmetrically divided between the rightward and leftward portions of the common atrium.

Congenital absence of superior venae cavae. Inferior vena cava empties into rightward portion.

Congenital absence of coronary sinus. Middle and great cardiac veins empty separately and directly into leftward portion of common atrium close to the A-V junction.

Ventricular inversion with hypertrophied, dilated anatomic right ventricle (systemic ventricle) and hypoplastic anatomic left ventricle (pulmonary ventricle) with anatomic mitral atresia.

Single common atrioventricular valve, right-dominant with anatomically tricuspid papillary apparatus. Valve had been excised and replaced with St. Jude mechanical valve.

L-transposition of great vessels with valvular and supravalvular pulmonic stenosis, but normal caliber aorta with 3 leaflets. Small perimembranous "malalignment" ventricular septal defect was later enlarged surgically to permit improved pulmonic flow ratio.

Apparent right-directed aortic arch.

Coronary ostia arising from appropriate sinuses of Valsalva; however, left main coronary artery is absent, instead two smaller ostia arise from left sinus of Valsalva.

Left-dominant coronary system with large ramus over lateral surface of anatomic right ventricle and large circumflex.

Permanent epicardial pacing wire on anteroapical surface of systemic ventricle.

Right anterior oblique view of this patient's heart showing opened small left ventricle, pulmonic stenosis, pulmonary vascular hypoplasia, and VSD. Note absence of SVC and large, posteriorly directed IVC. No conclusions could be made about atrial situs due to absence of other organ clues and abnormal disposition of the two atrial appendages. Presumably upper body venous return joined the IVC through anomalous azygous networks, as no major IVC tributaries were seen above the diaphragm, nor were any extracardiac systemic-to-pulmonary vein shunts found.

Left lateral view of the same heart, showing massive, coarse trabeculation of the systemic ventricle and the flat arch of the aorta. The ligamentum arteriosum was close to the base of the left pulmonary artery branch, which passed under the aortic arch. The cardiac veins can be seen emptying separately and directly into the common atrium as they pass the AV groove.

These views show the heart of a 34-year-old man with right aortic arch and L-transposition with ventricular inversion. The patient had only mild exertional limitation until the last eight months of life, in which progressive systemic ventricular failure was noted. Although the patient died suddenly at rest, there was no history of AV block or bradycardia.

Features include:

Normal atrial situs and venous anatomy.

Intact atrial and ventricular septum.

AV valve rings are in the same plane.

Delicate, often fenestrated papillary muscles arising from septum and freewall of anatomic left ventricle, and absence of moderator band therein.

Middle cardiac vein drains to right atrium separately from coronary sinus but in the same region anteromedial to the Eustachian valve remnant.

Trileaflet aortic valve with right and left coronary systems arising in their usual cusps.

Left-dominant coronary system.

Right anterior oblique view of this patient's heart showing opened anatomic left ventricle with fine LV type trabeculations and thin but nondilated wall.

Left lateral view of the same heart, showing large, coarse RV type trabeculation and generalized hypertrophy. Moderator band is massive and gives rise to prominent papillary muscles.