DiGeorge Syndrome in a 32-year-old male: A Cadaver Study
Date
ORCID
Journal Title
Journal ISSN
Volume Title
Publisher
Abstract
Background:
DiGeorge Syndrome (DGS) is one of the most encountered chromosomal syndromes in the population and is marked by the deletion of 22q11.2. Phenotypic expression varies widely between patients. Main features include cardiac and conotruncal abnormalities, craniofacial anomalies including cleft palate, thymic hypoplasia, hypocalcemia, and scoliosis. The branching pattern of the great vessels is known to be highly variable in DGS and a unique manifestation is found in this case.
Case Information:
This case report examines a 32-year-old deceased male with DGS, and a history of atrial fibrillation, pulmonary atresia-ventricular septal defect, pulmonary artery stenosis, pulmonary hypertension, and six heart surgeries. The cause of death was unspecified natural causes. Initial dissection of the thoracic cavity revealed clear signs of cardiomegaly and a severe scoliotic curve extending to the lumbar region. Further heart dissection revealed sutures and pericardial reconstruction confirming previous surgeries, likely to reconstruct the greater vessels. External findings include an aortic arch variant consisting of absent brachiocephalic trunk, a unique branching pattern of the great vessels directly from the aorta, and the wrapping of the proximal descending aorta around the trachea before descending. Pulmonary trunk adhesion to the heart's surface via scar tissue indicates surgical reconstruction. The left pulmonary artery was significantly constricted while the right pulmonary artery was expanded with immediate branching into smaller segments upon entering the lung, suggesting that more blood was shunted into the right lung. The right atrium appeared significantly enlarged with appropriate size compensations noticed in pectinate muscles and crista terminalis. The right auricle was small and only observable internally. The coronary sinus was abnormally enlarged, comparable in size to the opening of the inferior vena cava. Circular shaped scar tissue on the external surface of the sinus indicates a surgical correction. The right ventricle contained an abnormally enlarged moderator band. Dense scar tissue stenosis was visualized along the pulmonary outflow valve with sutures present along the entire circumference of outflow tract prior to pulmonary artery bifurcation indicating surgical reconstruction. Additional sutures were observed inferior to the circumferential sutures along the wall between the aorta and pulmonary trunk, potentially to seal a prior communicating shunt. The pulmonary veins and left atrium appeared normal; however, possible stenosis of the bicuspid valve was noted but further assessment is needed to confirm. The left ventricle showed enlarged papillary muscles and chordae tendinea which are hypothesized to be a byproduct of the overall increased heart size. The left ventricular wall was twice the thickness of the right ventricular wall, an expected proportion based on heart size and ventricular work. The aortic valves appeared slightly stenosed with cusp buildup. Coronary ostia appeared normal.
Conclusion:
This cadaveric case study reflects a unique cardiac presentation of DGS within an adult male. With DGS being a rather common chromosomal disorder with highly variable phenotypic expression, there is an importance to explore anatomical variants, their prevalence, and the needed surgical corrections present within patients to ensure that a more comprehensive diagnosis and care plan can be provided in future diagnostic settings.