Eosinophilic aortitis with thoracic aortic aneurysm and rupture in a captive-born owl monkey

Eosinophilic aortitis is a rare condition in animals and humans, and it has been occasionally reported associated with parasitic migration and with a poorly understood complex group of autoimmune vasculitides. Here, we describe a case of eosinophilic aortitis with thoracic aortic aneurysm and rupture in a captive-born owl monkey and discuss the differential diagnoses.

Spontaneous Aortic Dissecting Hematoma in Two Dogs

This report describes 2 cases of spontaneous aortic dissecting hematoma in young Border Collie and Border Collie crossbred dogs. Histology was performed in one of the cases involving an unusual splitting of the elastin present within the wall of the aorta, consistent with elastin dysplasia as described in Marfan syndrome in humans. The first case involved a young purebred Border Collie that died suddenly and the second case involved a Border Collie crossbred dog that died after a 1-month history of seizures. Gross lesions included pericardial tamponade with dissection of the ascending aorta in the former case and thoracic cavity hemorrhage, mediastinal hematoma, and aortic dissection in the latter. Histologic lesions in the case of the Border Collie crossbred dog included a dissecting hematoma of the ascending aorta with elastin dysplasia and right axillary arterial intimal proliferation.

Morphometric Properties of the Thoracic Aorta of Warmblood and Friesian Horses with and without Aortic Rupture

Rupture of the aorta is much more common in Friesians compared with other breeds of horse. Rupture always occurs adjacent to the scar of the ligamentum arteriosum. Previous histological examination of ruptured aortic walls suggested the presence of an underlying connective tissue disorder. Therefore, the aim of the present study was to compare the structural characteristics of the tunica media of the mid-thoracic aorta, distant to the lesion, in warmblood and Friesian horses with and without thoracic aortic rupture. In unaffected Friesian horses, the thickness of the tunica media, as well as the percentage area comprised of collagen type I, were significantly higher compared with the warmblood horses, supporting the hypothesis of a primary collagen disorder in the Friesian horse breed. However, in the tunica media of the affected Friesian horses there was no significant wall thickening. Moreover, the percentage area comprised of elastin was significantly lower, while the percentage area comprised of smooth muscle was higher, compared with unaffected Friesian and warmblood horses. These lesions are suggestive of an additional mild elastin deficiency with compensatory smooth muscle cell hypertrophy in affected Friesians.

Ruptured mycotic aortic aneurysm in a sooty mangabey (Cercocebus atys)

Mycotic aortic aneurysm is a local, irreversible dilatation of the aorta associated with destruction of the vessel wall by infection and is a grave clinical condition associated with high morbidity and mortality in humans. Rupture of aortic aneurysms can be spontaneous, idiopathic, or due to severe trauma, and the condition has been associated with bacterial and, rarely, fungal infections in humans and animals. Here, we describe a case of ruptured spontaneous aortic aneurysm associated with zygomycetic infection in a 21-y-old female sooty mangabey. The animal did not present with any significant clinical signs before being found dead. At necropsy, she was in good body condition, and the thoracic cavity had a large amount of clotted blood filling the left pleural space and surrounding the lung lobes. Near the aortic arch, the descending thoracic aorta was focally perforated (diameter, approximately 0.15 cm), and clotted blood adhered to the tunica adventitia. The aortic intima had multiple, firm, pale-yellow nodules (diameter, 0.25 to 0.5 cm). Histopathologically, these nodules consisted of severe multifocal pyogranulomatous inflammation intermixed with necrosis, fibrin, and broad, infrequently septate, thin-walled fungal hyphae. Immunohistochemistry revealed fungal hyphae characteristic of Mucormycetes (formerly Zygomycetes), and PCR analysis identified the organism as Basidiobolus spp. Dissemination of the fungus beyond the aorta was not noted. Spontaneous aortic aneurysms have been described in nonhuman primates, but this is the first reported case of a ruptured spontaneous aortic aneurysm associated with entomophthoromycetic infection in a sooty mangabey.

Acute aortic rupture in a dog with spirocercosis following the administration of medetomidine : clinical communication

Spirocercosis is an emerging disease in veterinary medicine. A strong suspicion of spirocercosis is usually evident after a thorough clinical examination and radiography of the chest has been performed. Lesions seen on radiography include an oesophageal mass, spondylitis and oesophageal air. Unfortunately, radiography is not diagnostic and additional diagnostic procedures are required to confirm the diagnosis. Endoscopy is commonly performed to diagnose the condition. The dog presented in this study had radiographic and clinical signs consistent with spirocercosis and definitive diagnosis was required. Shortly after sedation with medetomidine, the dog went into cardiac arrest and failed to respond to resuscitative measures. On post mortem, the diagnosis of spirocercosis was confirmed and the cause of death was identified as acute aortic rupture. Aortic aneurysms are not an uncommon finding and cause of acute death in dogs with spirocercosis. The acute rupture of the aorta in this case is most probably the result of cardiovascular changes associated with the administration of medetomidine. Medetomidine causes an acute rise in systemic vascular resistance with hypertension. The increase in shear stress across the weakened aortic wall resulted in rupture. Caution with the use of medetomidine in patients with spirocercosis is advised.

Postoperative rupture of an aortic aneurysmal dilation associated with a patent ductus arteriosus in a dog

OBJECTIVE

To describe an unusual case of fatal aortic aneurysm rupture after standard ligation of a left-to-right shunting patent ductus arteriosus (PDA) and review the literature concerning the causes of aneurysm and applicable medical physics of blood flow that may contribute to mural failure.

STUDY DESIGN

Clinical case report.

SAMPLE POPULATION

An 11-month-old female Brittany spaniel.

RESULTS

A PDA was diagnosed in the dog after referral for a grade IV/IV cardiac murmur. Diagnostic tests performed included a minimum database, thoracic radiography, and echocardiography. Conventional surgical ligation of the PDA was performed. The postoperative recovery from anesthesia was uneventful. Approximately 5 hours after surgery, the dog vocalized once and collapsed. All resuscitative efforts failed. Necropsy showed a large, spiral rupture of the cranial and dorsal wall of the aorta that extended from the left subclavian artery to 2 cm distal to the PDA-aorta junction. No evidence of intramural, perianeurysmal hemorrhage or inflammation was noted. Histopathologic examination of the ruptured aneurysm showed that the wall lacked a defined tunica intima and endothelial cell layer. A distinct separation of the thinned tunica media parallel to the elastic fibers was noted.

CONCLUSIONS AND CLINICAL RELEVANCE

Dilatation of the aorta near the area of a PDA is one of the recognized abnormalities associated with the condition. Aneurysmal dilatation results from and contributes to abnormal blood flow dynamics and increased aortic wall tension, which promotes expansion. Although an unusual and previously unreported sequela, rupture of the aneurysm should be considered a possible complication when ligation of a PDA with a conspicuous aortic aneurysmal dilation is performed.

Mycobacterium marinum dermatitis and panniculitis with chronic pleuritis in a captive white whale (Delphinapterus leucas) with aortic rupture

A 16-year-old female white whale, Delphinapterus leucas, died after nearly 18 months of chronic lymphopenia and pyogranulomatous dermatitis. Necropsy revealed rupture of the aorta with hemorrhage into the cranial mediastinum and between fascial planes of the ventral neck musculature. Multiple foci of ulcerative dermatitis and panniculitis were present across the thorax and abdomen and surrounded the genital folds. In addition, there was a chronic proliferative pleuritis with over 20 liters of histiocytic exudate in the thoracic cavity. Acid-fast bacteria consistent with Mycobacterium sp. were identified in sections of skin lesions and in cytospins of pleural exudate. Cultures of pleura and 1 skin lesion collected at necropsy yielded sparse growth of an acid-fast bacillus with colony characteristics and morphology consistent with Mycobacterium marinum. Polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) analysis confirmed the presence of M. marinum DNA in samples of skin. This is the first documented occurrence of mycobacteriosis in a white whale and is a unique presentation of mycobacterial dermatitis and panniculitis with chronic pleuritis in a cetacean. The improved PCR-RFLP protocol utilized in this case unifies techniques from several protocols to differentiate between species of Nocardia and rapidly growing mycobacteria clinically relevant to aquatic animals.

Aortic root disease in four horses

Clinical findings in 4 horses with aortic root disease are described. Three of the horses had aneurysms of the right aortic sinus, and in 2 of the 3, the aneurysm ruptured, creating a fistula between the aorta and right ventricle. One of these horses had had a murmur since birth, and the aortic sinus aneurysm may have been a congenital anomaly. In a second horse, the aneurysm may have been an acquired condition that developed secondary to chronic aortic regurgitation. Another horse had a large subendocardial hematoma associated with dissection of blood from the aorta to the interventricular septum because of a tear in the aortic root near the right aortic sinus. Ventricular ectopy and signs of abdominal pain were the most common initial signs in these horses.

Dissecting thoracoabdominal aortic aneurysm in a free-ranging Florida panther (felis concolor coryi)

A 12-yr-old female free-ranging Florida panther (Felis concolor coryi) was found dead in good flesh. The panther had a ruptured thoracoabdominal aneurysm and 0.5 L of unclotted blood in its thorax. Intimal plaques 6.0 x 3.0 x 3.0 cm and 4.0 x 3.0 x 1.0 cm were present in the thoracic and abdominal aorta extending below the bifurcation of the renal arteries. Histologic examination revealed necrohemorrhagic aortitis with a mixed inflammatory infiltrate of lymphocytes, macrophages, and neutrophils. Death was almost certainly due to exsanguination and hypovolemic shock secondary to the ruptured aneurysm, and the aortitis with the resultant aneurysm may have been secondary to an infectious or a toxic process. This is the first reported death of a free-ranging mammal from a ruptured aortic aneurysm.

[Aortic rupture in poultry: a review]

Mortality in poultry due to aortic rupture is characterized by sudden death. The condition is seen in fast-growing male turkeys but has also been described in chickens, ostriches, and waterfowl. Losses in affected flocks usually only reach 1-2%. Post-mortem examination shows a large blood clot in the abdominal cavity subsequent to a dissecting aneurysm. Fragmentation of elastic fibres and degenerative changes of smooth muscle cells are seen in the region of the rupture. Intimal sclerotic plaques are present adjacent to the site of rupture. Copper deficiency, hypertension, hormonal influences, diet, lathyrism, zinc deficiency, pharmaceuticals, and parasites are precipitating factors for aortic rupture. Field studies suggest that favourable results are obtained with reserpine and copper as treatment for ruptured aorta.

Rupture of the left aortic sinus into the pulmonary artery in a Dalmation dog

An 18-month-old male Dalmatian dog was presented for veterinary evaluation after the pet owner observed a sudden onset of weakness. An acquired continuous cardiac murmur was detected on physical examination. Two-dimensional echocardiographic examination revealed structural abnormalities of the proximal aorta and pulmonic valve. Doppler echocardiographic studies and cardiac catheterization demonstrated the presence of a proximal aorticopulmonary shunt. A diagnosis of left aortic sinus rupture and aorticopulmonary fistula was made. Antemortem diagnosis of aortic sinus rupture in the dog has not, to our knowledge, been reported previously. The anatomical variant of left aortic sinus rupture resulting in the development of a fistula from the aorta to the main pulmonary artery is, apparently, uncommon in all species.

Aorto-cardiac fistulas in seven horses

This report describes the history, clinical, electrocardiographic and echocardiographic findings, treatment, outcome and post-mortem findings in seven horses with aorto-cardiac fistula. Affected horses included 5 stallions, one gelding and one mare; 2 each of the Thoroughbred, Arabian and Standardbred breeds and one Thoroughbred-cross with a mean +/- s.d. age of 12 +/- 4 years, range 6-18 years. The presenting signs were acute distress (four horses), exercise intolerance (two horses) and the lesion was detected during a routine examination in one horse. Five horses had monomorphic ventricular tachycardia on admission and one other had a history of this arrhythmia. Five horses had a characteristic continuous murmur loudest in the right fourth intercostal space. Echocardiography (six horses) and/or post-mortem examination (four horses) revealed the horses had aorto-cardiac fistulas arising from the right aortic sinus in all five horses in which the site was recorded. Two horses had ruptured aneurysmal dilatations of the aortic wall at this site. Fistulas extended into the right ventricle in four horses; the right atrium in two horses, the left ventricle in one horse, and five horses had dissecting tracts in the septal myocardium. Horses survived for periods ranging from 24 h to 4 years. Aorto-cardiac fistula should be considered in the differential diagnosis for horses presenting with acute distress, bounding arterial pulse, a right-sided continuous murmur and/or monomorphic ventricular tachycardia, particularly in middle-aged or older stallions. Echocardiography is the technique of choice for confirming the diagnosis and demonstrating accompanying cardiac changes.

Comparison of immunity and resistance to diseases in male and female poultry breeders in Lebanon

The immune responses following vaccination and resistance to diseases were compared in male and female meat poultry breeders of the same flock. Female poultry breeders maintained antibody titres to Newcastle disease virus and infectious bronchitis virus up to the fifty-fifth day following vaccination, whereas those of the males declined significantly over the same period of time (P < 0.05). In the same flock, outbreaks of Gumboro disease (60 to 62 days of age), coccidiosis (68 to 74 days of age) and aortic rupture (99 to 112 days of age) produced significantly higher losses in males. Following vaccination against fowl pox by the wing web method, 96.7% of females had a vaccine reaction (vaccine take) compared to none of the males. Immune injuries, following vaccination, were observed in 85% of the males compared to none of the females. The immune injuries included appearance of facial papules, vesicles, and reddish brown to black scabs.

Cardiovascular lesions in bovine Marfan syndrome

Bovine Marfan syndrome is a genetic disease with many of the clinical and pathologic manifestations of human Marfan syndrome. Major manifestations include ectopia lentis and aortic dilatation, aneurysm, and rupture. Affected cattle have a defect in fibrillin metabolism similar to that in human patients. Ten cattle were followed and their disease progression and lesions documented. Ages ranged from a term fetus (No. 9) to a 4-year-old cow (No. 4); three animals were male (Nos. 1-3) and seven were female (Nos. 4-10). Of eight animals (80%) that died or were euthanatized (Nos. 1-3, 5-9), six (75%) had severe cardiovascular lesions identified at necropsy. Gross cardiovascular lesions of bovine Marfan syndrome included cardiac tamponade secondary to aortic rupture (animal Nos. 3, 6, 8), dissecting aneurysms of the aorta and pulmonary artery (animal No. 5), and intrauterine cardiac tamponade secondary to rupture of the pulmonary artery (animal No. 9). Microscopically, Verhoeff Van Gieson-stained sections of aorta contained severe fragmentation of the elastic laminae in the aortic media, but the cystic medial necrosis seen in human Marfan aortae was not identified, even in the chronic aortic dissection. Ultrastructurally, affected aortic tissue was characterized by thin, dark elastic fibers with abundant, tangled microfibrils on the periphery. Swirls of collagen fibers and bundles of hypertrophic smooth muscle cells replaced damaged elastic laminae. Gross and microscopic cardiovascular lesions in bovine Marfan syndrome are similar to those in human Marfan syndrome. Bovine Marfan syndrome is a valuable model for investigation of molecular pathogenesis and treatment of human Marfan syndrome.

Aortic rupture in ostrich associated with copper deficiency

Four cases of aortic rupture in ostrich associated with deficient levels of copper in the liver are presented. The aortic lesions are consistent with vascular lesions described in turkeys and chickens with copper deficiency.

A biophysical and histological analysis of factors that lead to aortic rupture in normal and lathyritic turkeys

These experiments were designed to determine if local differences in elastic properties or wall structure contributed to the development of aortic rupture in turkeys. Static elastic properties were measured from pressure-volume curves of cylindrical segments of upper and lower thoracic aorta and innominate artery in two groups of lathyritic birds and two age-matched control groups. The biggest changes were in the young lathyritic group that was on 0.04% beta-aminoproprionitrile at 3 weeks of age and continued for 2, 3, or 4 weeks. Much smaller changes were seen in the older group that started on 0.05% beta-aminoproprionitrile at 6 weeks of age for 10 days and then 0.02% beta-aminoproprionitrile for the next 9-12 weeks. The biggest changes were seen in the abdominal aorta, which ruptured spontaneously in 50% of the young lathyritic group. The birds had a marked decrease in the number of elastin layers per unit wall thickness. Analysis of the elastic diagrams showed that the elastance of both elastin and collagen were altered in the young lathyritic group. Rupture appeared to follow partial dissection of plaques, but true longitudinal dissection did not occur.

Rupture of an aortic sinus aneurysm in a 15-year-old broodmare

A 15-year-old, Standardbred broodmare with an aortic sinus aneurysm developed rupture of the aneurysm with subsequent rupture of a tricuspid valve chorda tendinae, tricuspid regurgitation, acute right-sided congestive heart failure, and pulmonary thromboembolism. Shunting of blood from the aorta through the ruptured aneurysm into the right ventricle resulted in decreased renal perfusion and acute renal failure. Initially, treatment of the mare with analgesics, fluids, and digoxin resulted in clinical improvement, but the mare's condition deteriorated after 8 days and the mare was euthanatized due to unrelenting pain and a poor prognosis. Echocardiography was useful in diagnosis of the cardiac disease in the broodmare.

Rupture pressure of elastic and muscular aortic segments from hypertensive and hypotensive turkeys

Blood pressures and heart rates were recorded from two groups of turkeys in two trials. In trial one 20 turkeys, 36 weeks of age and in trial two 24 turkeys, 14 weeks of age, were used. Immediately after blood pressures and heart rates had been determined, the turkeys were killed and vascular tissues were excised. Equal numbers from hypertensive and hypotensive lines of turkeys were used in each trial to determine the rupture pressure of both the elastic and muscular segments of the aorta. When values for the two trials were combined, mean hydrostatic pressures of 1478, 1804, and 794 mm Hg respectively were required to rupture the most caudal abdominal aortic segment, the adjacent cranial abdominal segment, and the thoracic aortic segment. There was a significant difference between the two lines for blood pressure in both trials and for heart rate in trial 2. There were no statistically significant correlations between blood pressure, atherosclerotic plaque score and rupture pressure. Birds fed on a diet containing added fat and cholesterol had significantly lower blood pressures than the birds fed on the other two diets. Birds receiving added dietary cholesterol and fat had lower heart rates than birds fed on the diet with added fat only. Lower plaques scores were evident in the caudal abdominal aorta of the birds fed on the control diet compared to birds fed on the other two diets.

Necrosis and rupture of the aorta and pulmonary trunk in four horses

Four horses are described with rupture of the aortic arch and pulmonary trunk which resulted in a fistula between these vessels. Ruptures were located near the ligamentum arteriosum. Histological examination of the vessel walls revealed media necrosis which was probably due to intimal thickening and/or medial fibrosis of the vasa vasorum.

Cyclocoelum mutabile infection and aortic rupture in an American coot (Fulica americana)

An American coot (Fulica americana) was found dead within the enclosed research compound of the South Central Poultry Research Laboratory at Mississippi State, Mississippi. Gross and microscopic examinations revealed the bird to be in good body condition; however, blood from the beak cavity and external nares was present. Biliary congestion, hemopericardium, blood-filled air sacs, and a ruptured, ascending aorta were also noted. Nineteen trematodes (Cyclocoelum mutabile) were found within the body cavity at necropsy. Bacteriological examination revealed the presence of Escherichia coli in both the heart and liver and Pseudomonas putida in the liver only. No virus was isolated.

Nephroblastoma with associated aortic rupture in a rat

A nephroblastoma was diagnosed in a 6-month-old, male rat which died unexpectedly. The right kidney was replaced by a large, white, irregularly shaped mass. Microscopically, the mass consisted of an embryonic blastema showing epithelial differentiation into immature tubules and glomeruloid structures. An aortic aneurysm and aortic rupture were present within the thoracic cavity. It was suspected that the aortic rupture was secondary to hypertension mediated through the renin-angiotensin system.

Copper salts for growth stimulation and alleviation of aortic rupture losses in turkeys

Approximately 4000 Large White, day-old turkey poults were used in a series of eight experiments to study the effects of dietary copper supplementation. The hens were grown to 15 or 16 weeks and toms to 24 weeks of age. Either copper as the oxide or sulfate (hydrate) at 120 ppm stimulated growth up to 10% with a concurrent reduction in feed requirement. Levels of 60 ppm were not adequate, whereas 240 ppm were not toxic. There was a greater response to copper in the presence of 4-nitrophenylarsonic acid (4-nitro) or with low protein diets. In two of the eight studies copper enhanced aortic elastin content. Incidence of aortic rupture was greater in the presence of 4-nitro and was reduced by one-half through copper supplementation. Liver copper was not altered by 60 or 120 ppm Cu; 240 ppm caused a significant increase.

Copper levels in livers of turkeys with naturally occurring aortic rupture

Lesions of connective tissue in the media of the aorta, including ruptures, were produced with experimental copper deficiency in turkey poults. The copper and molybdenum contents in the livers of 12 turkeys that had succumbed to naturally occuring aortic ruptures were measured to determine if field cases of the disease are etiologically related to copper deficiency. Half of the livers contained less than 10 ppm copper, and the others contained 10--20 ppm copper. Molybdenum levels were less than 1 ppm.

Dissecting aneurysm and cardiac tamponade

A Gir cow which died suddenly had a dissecting aortic aneurysm. Death was caused by cardiac tamponade which followed rupture of the intrapericardial aorta after it had been damaged by onchocercosis.

Spontaneous aortic rupture in turkeys and the vascularization of the aortic wall

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Aortic ring rupture in stallions

Eight cases of acquired rupture of the aortic ring in the right coronary sinus with dissection (cardioaortic fistula) into the interventricular septum and into the right ventricle have been described in stallions. It is postulated that the ruptures are due to increased blood pressure during breeding and the direction of a recoiling column of blood against an area of anatomic weakness.