MULTIDETECTOR-ROW COMPUTED TOMOGRAPHY PATTERNS OF BRONCHOESPHAGEAL ARTERY HYPERTROPHY AND SYSTEMIC-TO-PULMONARY FISTULA IN DOGS

Case report: Echocardiographic and computed tomographic features of congenital bronchoesophageal artery hypertrophy and fistula in a dog

Introduction

Studies on aberrant bronchoesophageal arteries are limited. Herein, we report a case of a multi-origin systemic-to-pulmonary shunt with suspected bronchoesophageal artery hypertrophy and fistula in a dog.

Case report

A 4-year-old castrated male beagle weighing 11 kg underwent routine medical screening. Physical examination revealed a right-sided continuous murmur of grades 1-2. Thoracic radiography revealed a mild cardiomegaly. Echocardiography revealed a continuous turbulent shunt flow distal to the right pulmonary artery (RPA) branch from the right parasternal short axis pulmonary artery view. Computed tomography demonstrated systemic-to-pulmonary shunts originating from the descending aorta at the level of T7-8, the right 5th and 6th dorsal intercostal arteries, and the right brachiocephalic trunk, which formed anomalous networks around the trachea and esophagus that anastomosed into a large tortuous vessel at the level of T6-7 and entered the RPA. Surgical ligation of multiple shunting vessels was performed. Postoperative echocardiography and computed tomography showed decreased left ventricular volume overload and markedly decreased size of the varices. Additionally, most of the shunting vessels were without residual shunt flow.

Conclusion

The present study provides information regarding imaging features and the successful surgical management of multiple systemic-to-pulmonary shunts originating from the descending aorta, right brachiocephalic trunk, and intercostal arteries and terminating at the RPA. Multimodal imaging features after surgical ligation have also been described.

Esophageal varices in dogs: A retrospective case series

BACKGROUND

Esophageal varices (EV) are abnormally dilated veins in the esophagus caused by alterations of blood flow or pressure. Esophageal variceal hemorrhage is a major complication of hepatic disease in humans, but a lack of information exists regarding associated adverse events in dogs.

OBJECTIVE

To describe the clinical manifestations and associated etiologies and outcomes of dogs with EV.

ANIMALS

Twenty-five client-owned dogs with EV diagnosed via computed tomography (CT), endoscopy, or fluoroscopy.

METHODS

Retrospective case series. Cases were identified by review of the hospital imaging records database between 2010 and 2020. Signalment, clinical signs, and outcomes were documented. When present, additional collateral vasculature was also recorded. Cases were subcategorized into suspected etiology based upon the anatomic location or absence of an attributable underlying disease process, as well as the direction of blood flow.

RESULTS

Twenty-four of 25 cases were identified via CT, with a prevalence of 0.012% (24/1950 total studies). Presenting clinical signs were nonspecific, and more likely because of the underlying cause as opposed to complications secondary to EV themselves. Etiologic anatomic locations were similar in occurrence between the abdomen (N = 14) and thorax (N = 11). All cases with an abdominal etiologic location had presumed or confirmed portal hypertension and 9/11 cases with a thoracic etiologic location had pulmonary, caval, or systemic hypertension. No cases died or were euthanized as a direct result of EV or associated hemorrhage.

CONCLUSIONS AND CLINICAL IMPORTANCE

Esophageal varices are rarely reported in dogs and commonly identified concurrently with portal, pulmonary, and caval hypertension. Hemorrhage is not a common clinical manifestation of EV.

Anomalies of the aortic arch in dogs: evaluation with the use of multidetector computed tomography angiography and proposal of an extended classification scheme

BACKGROUND

Congenital anomalies of the aortic arch are important as they may be associated with vascular ring anomalies. The most common vascular ring anomaly in dogs is a persistent right aortic arch. However, published data of the distribution of the different types of vascular ring anomalies and other aortic arch anomalies are lacking. The objective of this retrospective descriptive study was to evaluate both the prevalence and the different types of aortic arch anomalies that can be detected using thoracic computed tomography (CT) examination. Archived thoracic CT examinations acquired between 2008 and 2020 at a single institution were retrospectively evaluated by 2 evaluators for the prevalence and type of aortic arch anomaly. Breed, age, and presenting complaint were obtained from the medical record system.

RESULTS

A total of 213 CT studies were evaluated; 21 dogs (21/213, 9.9%) showed a right aortic arch and a left ligamentum arteriosum with compression of the esophagus. The following incidental additional findings were detected: aberrant left subclavian artery (17/21, 76.2%), branching from the persistent ductus arteriosus (PDA) (1/21, 4.8%), left-sided brachiocephalic trunk (3/21, 14.3%), bicarotid trunk (17/21, 81.0%), double aortic arch (1/21, 4.8%). One hundred ninety two dogs (192/213, 90.1%) showed a left aortic arch without esophageal compression. The following additional abnormalities were obtained in those dogs with left aortic arch: aberrant right subclavian artery (3/192, 1.6%) without clinical signs of esophageal compression, aberrant vessel branching from the aorta into the left caudal lung lobe (2/192, 1.0%), focal dilatation of the left or right subclavian artery (2/192, 1.0%), bicarotid trunk (1/192, 0.5%).

CONCLUSION

Similar to previous studies an aberrant left subclavian artery is the most common additional finding in dogs with persistent right aortic arch. Newly, a left-sided brachiocephalic trunk was identified in 14.3% of the dogs with a persistent right aortic arch; no additional compression was caused by the left sided brachiocephalic trunk. Similarly, aberrant right subclavian artery can be an incidental CT finding without causing compression of the esophagus.

Fatal hemoptysis after bronchoscopic biopsy in a dog

An 8‐year‐old 24.6 kg mixed breed dog underwent bronchoscopy for evaluation of a persistent progressive cough. Bronchoscopy documented a markedly thick and irregular, cobblestone appearance of the mucosa. A bronchoscopic biopsy was obtained; immediately after the biopsy, a large amount of hemorrhage poured from the endotracheal tube. Multiple efforts to control the hemorrhage were unsuccessful and the dog suffered a cardiopulmonary arrest and could not be revived. A necropsy was performed, which was significant for pallor, evidence of prior heartworm disease, prominent bronchial arteries, and erosion of the submucosal vessels at the site of the biopsy. The cause of death was hemorrhage associated with transbronchial biopsy of an enlarged bronchial artery associated with heartworm disease. This report describes a rare complication of a routine diagnostic procedure.

Transcatheter embolization of systemic-to-pulmonary artery fistulas in a dog using embolization coils and silk suture

A 4-month-old intact female Cavalier King Charles spaniel presented for evaluation of a left, basilar continuous murmur. Transthoracic echocardiography suggested anomalous vessels around the main pulmonary artery, and computed tomography angiography revealed two systemic-to-pulmonary artery fistulas. Transcatheter embolization of these fistulas was achieved with a combination of embolization coils and silk suture threads delivered through a microcatheter.

Presumptive non-cirrhotic bleeding esophageal varices in a dog

An 8‐year‐old male American Staffordshire terrier was admitted for evaluation of chronic episodes of ptyalism and hematemesis after exercise. Abnormalities were not detected on routine clinicopathological tests, thoracic radiography, and abdominal ultrasonography. Endoscopic examination revealed a labyrinthine network of severely distended, hemorrhagic esophageal blood vessels. Computed tomography angiography demonstrated a network of para‐esophageal vessels that communicated with the celiac artery caudally and the brachiocephalic trunk cranially, consistent with a diagnosis of non‐cirrhotic esophageal varices. This is a report of exercise, ptyalism, and hematemesis secondary to presumptive, non‐cirrhotic, bleeding esophageal varices in a dog.