Persistent truncus arteriosus--an autopsy study of 16 cases

Common Arterial Trunk Associated with Functionally Univentricular Heart: Anatomical Study and Review of the Literature

Common arterial trunk (CAT) is a rare congenital heart disease that is commonly included into the spectrum of conotruncal heart defects. CAT is rarely associated with functionally univentricular hearts, and only few cases have been described so far. Here, we describe the anatomical characteristics of CAT associated with a univentricular heart diagnosed in children and fetuses referred to our institution, and we completed the anatomical description of this rare condition through an extensive review of the literature. The complete cohort ultimately gathered 32 cases described in the literature completed by seven cases from our unit (seven fetuses and one child). Four types of univentricular hearts associated with CAT were observed: tricuspid atresia or hypoplastic right ventricle in 16 cases, mitral atresia or hypoplastic left ventricle in 12 cases, double-inlet left ventricle in 2 cases, and unbalanced atrioventricular septal defect in 9 cases. Our study questions the diagnosis of CAT as the exclusive consequence of an anomaly of the wedging process, following the convergence between the embryonic atrioventricular canal and the common outflow tract. We confirm that some forms of CAT can be considered to be due to an arrest of cardiac development at the stages preceding the convergence.

Morphological variability of the arterial valve in common arterial trunk and the concept of normality

OBJECTIVE

Until now, no study established a morphometric evaluation of the truncal valve dysplasia and a description of its different presentation patterns. Thus, authors conducted an anatomopathological study describing the gross features and histological findings of the truncal valve.

METHODS

50 common arterial trunk (CAT) specimens were examined. The number of valvar leaflets was determined and valvar dysplasia was classified as absent, mild, moderate or severe. Selected leaflets were sectioned and submitted to histological analysis and linear measurements (thickness, length and area), besides quantification of collagen area fraction.

RESULTS

28 (56%) valves presented three, 15 (30%) four and 7 (14%) two leaflets. Valvar dysplasia was absent in 13 (26%) cases, mild in 19 (38%), moderate in 6 (12%) and severe in 12 (24%). A significant association was found between the presence of four leaflets and valvar dysplasia (p<0.001). Single coronary ostium was more common in two-leaflet cases than in three-leaflet cases (p=0.037). Leaflets medial thirds were thicker in the more dysplastic valves (p=0.006) and in those presenting anarchic collagen distribution (p=0.002).

CONCLUSIONS

CAT semilunar valves present two main patterns. The first characterised by three leaflets and absent or mild dysplasia and the second by four leaflets and severe dysplasia. Still, great variability regarding thickness, microscopic organisation of the extracellular matrix and proportions of leaflets' dimensions exists, which may impact on the surgical outcomes.

Common Arterial Trunk in a 3-Day-Old Alpaca Cria

A 3-day-old alpaca cria presented for progressive weakness and dyspnea since birth. Complete bloodwork, thoracic radiographs, and endoscopic examination of the nasal passages and distal trachea revealed no significant findings. Echocardiogram and contrast study revealed a single artery overriding a large ventricular septal defect (VSD). A small atrial septal defect or patent foramen ovale was also noted. Color flow Doppler and an agitated saline contrast study revealed bidirectional but primarily right to left flow through the VSD and bidirectional shunting through the atrial defect. Differential diagnosis based on echocardiographic findings included common arterial trunk, Tetralogy of Fallot, and pulmonary atresia with a VSD. Postmortem examination revealed a large common arterial trunk with a quadricuspid valve overriding a VSD. Additionally, defect in the atrial septum was determined to be a patent foramen ovale. A single pulmonary trunk arose from the common arterial trunk and bifurcated to the left and right pulmonary artery, consistent with a Collet and Edwards' type I common arterial trunk with aortic predominance. Although uncommon, congenital cardiac defects should be considered in animals presenting with clinical signs of hypoxemia, dyspnea, or failure to thrive.

A case of pentacuspid pulmonary valve

A pentacuspid pulmonary valve is a rare congenital anomaly. The present report describes a case of pentacuspid pulmonary valve encountered during the autopsy of a 50-year-old man with a ruptured abdominal aortic aneurysm. The pentacuspid pulmonary valve had three relatively equal cusps and two smaller cusps. In this case, a tricuspid aortic valve was identified with normal structure and no evidence of heart failure was found clinically or pathologically.

Benzofuranyl ureas with potent cardiovascular teratogenicity in rats

Studies of embryo-fetal development in rats were conducted with two 5-lipoxygenase inhibitors. SB-202235 (1,000 mg/kg/day) or SB-210661 (50, 100, or 500 mg/kg/day) was administered orally by gavage to female rats on days 6-17 postcoitus (pc) or days 7-16 pc. SB-202235 (1,000 mg/kg/day) and SB-210661 (100 mg/kg/day) reduced maternal body weight gain for the treatment period by 16% and 21%, respectively, relative to controls. SB-202235 (1,000 mg/kg/day) or SB-210661 (50 or 100 mg/kg/day), did not affect numbers of resorptions, dead or live fetuses/litter, but 500 mg/kg/day of SB-210661 caused 100% embryo lethality. SB-202235 (1,000 mg/kg/day) and SB-210661 (50 and 100 mg/kg/day) reduced fetal body weight by 15-30% and produced extensive cardiovascular malformations, as well as diaphragmatic hernias. SB-210661 also caused thymic abnormalities and cryptorchidism. Cardiovascular defects included abnormalities in aorticopulmonary septation, the aortic arch, pulmonary trunk, and ventricular septal defects are discussed relative to comparable human syndromes of cardiovascular malformation.