Pathogenesis of persistent truncus arteriosus in light of observations made in a dog embryo with the anomaly

Among 36 embryos obtained from a strain of Keeshond dogs in which there is a large incidence of spontaneously occurring conotruncal anomalies, a specimen with persistent truncus arteriosus, type 1 was found. The embryo had a crown-rump length of 20 mm. The specimen was serially sectioned and a wax plate reconstruction was made of the heart and proximal great vessels at a magnification of X100. The truncal valve was quadricuspid and dysplastic; associated anomalies were a right subclavian artery arising anomalously from the descending aorta, a single coronary artery, an absent ductus arteriosus and a small persistent left cranial (superior) vena cava. The truncus cushions were hypoplastic, had failed to fuse and each had simply produced an arterial cusp. The observations made on this embryo support the view that in persistent truncus arteriosus there is failure of septation of the truncus arteriosus. No evidence was found in favor of the concept that persistent truncus arteriosus represents a form of tetralogy of Fallot with atresia of the subpulmonary infundibulum and partial or complete absence of the aorticopulmonary septum.

Persistent truncus arteriosus in a cat

A 5-month-old male domestic cat presented with a history of rapid, heavy breathing and cyanosis after exercise. Physical examination showed an abnormal respiratory pattern with an increased rate and stress-induced cyanosis. Auscultation revealed tachycardia and a grade 5/6 systolic murmur best heard over the left base. Radiographs showed evidence of right atrial and ventricular enlargement with distended pulmonary vessels and an enlarged ascending aorta. An echocardiographic examination revealed a dilated right atrium, eccentric right ventricular hypertrophy and an overriding aorta associated with a large ventricular septal defect (VSD). The pulmonary trunk could not be identified by echocardiography. Doppler and saline contrast studies showed large right-to-left shunting through the VSD. These findings were compatible with persistent truncus arteriosus, which was confirmed at necropsy.

Persistent Truncus Arteriosus in a 6-year-old Cat

Truncus arteriosus (TA) was diagnosed in a 6-year-old neutered female domestic short-haired cat by two-dimensional and M-mode echocardiography, colour flow imaging and spectral Doppler examinations. The lesion was characterized by a single large artery originating from the right ventricle. A single ascending aorta and a single pulmonary trunk arose from the common arterial trunk. The residual pulmonary trunk immediately split into left and right branches. The lesion was identified as a type I (TA). This case is of interest because it is the first reported echo-Doppler description of such a malformation in felines, and because of the age of the cat at the time of diagnosis.

Persistent truncus arteriosus and patent foramen ovale in a Simmentaler x Braunvieh calf

A Simmentaler x Braunvieh calf had been anorexic during its first 36 hours of life, had a loud heart murmur and was suspected to have pneumonia. In the light of the results of radiographic and echocardiographic examinations, right heart catheterisation and angiography, a diagnosis of persistent truncus arteriosus and patent foramen ovale was made. The diagnosis was confirmed on postmortem examination.

Persistent truncus arteriosus in a diprosopic newborn calf

A newborn diprosopic female calf had a partially duplicated head with two faces each exhibiting a mouth, a snout, an anomalous incomplete mandible, two eyes and a lateral ear. A single ear with two small auditory canals was present on the midline between the two medial eyes. A type 1 persistent truncus arteriosus and hypoplasia of the thoracic portion of thymus were the most outstanding extracranial defects. In the heart, a persistent foramen secundum and a large patent foramen ovale allowed communication between the right and left atria. In the right ventricle, the small conus arteriosus was separated in part from the inflow tract by an anomalous 'septomarginal muscular septum'. An interventricular septal defect was also present. A large undivided truncus arteriosus, exhibiting a tricuspid truncal valve at its origin, arose for the most part from the conus arteriosus of the right ventricle. The truncus gave rise to the brachiocephalic trunk, the aortic arch, a small pulmonary trunk, from which the left and right pulmonary arteries emerged, and two coronary arteries. The etiology and pathogenetic mechanisms implicated in the appearance of persistent truncus arteriosus are reviewed. It is suggested that a deficit or insufficiency in the cranial neural crest may play a role in the pathogenetic mechanisms leading to the production of persistent truncus arteriosus and related defects in cephalic duplications.

Cardiac Truncus Arteriosus in an Eastern Black Rhinoceros (Diceros bicornis michaeli)

This case report describes congenital truncus arteriosus in a 1-month-old Eastern black rhinoceros (Diceros bicornis michaeli). From the first day of life the animal was underweight and from the 22nd day of life displayed respiratory signs that exacerbated with time leading eventually to collapse and death. Post-mortem examination revealed a single truncus arteriosus originating from the right ventricle leading to two separated pulmonary arteries and the aorta, with the ventricular septum showing a focal communicating defect. Based on the gross examination and current human classifications, the truncus arteriosus was classified as type III or A2. This is the first description of persistent truncus arteriosus in an Eastern black rhinoceros.

Persistent truncus arteriosus in a rhesus monkey (Macaca mulatta)

A 47-day-old female rhesus macaque (Macaca mulatta) was examined because of a severe holosystolic heart murmur (grade 5/6) and signs of congestive heart failure. Results of physical examination, thoracic radiography, and cardiac ultrasonography confirmed an advanced stage of congestive heart failure. Due to the animal's age and clinical signs of disease, a congenital heart defect was suspected. Necropsy revealed a rare congenital heart defect known as persistent (common) truncus arteriosus.

The angiocardiographic diagnosis of a persistent truncus arteriosus in a foal

Persistent truncus arteriosus is a relatively rare cardiac anomaly which is associated with a single large artery arising from the ventricles. An interventricular septal defect is invariably present. The vessel gives origin to the pulmonary trunk, aorta and coronary arteries. A description of the angiocardiographic diagnosis of this condition is given as well as a general review of the relative developmental anatomy.

Persistent truncus arteriosus communis in a two-year-old steer

A two-year-old Hereford-cross steer was presented for routine embalming. Dissection of the heart and great vessels revealed a persistent truncus arteriosus type A2. Despite complete mixing of pulmonary and aortic blood, this animal had survived to adulthood.