Role of computed tomography angiography in the differentiation of feline truncus arteriosus communis from pulmonary atresia with ventricular septal defect

A Retrospective Study of Sildenafil Administration in 55 Cats with Cardiopulmonary Disease (2009-2021)

Sildenafil is a drug used to successfully manage a variety of cardiopulmonary disorders in people and dogs, but there is limited information on its use in cats. The objective was to review the medical records of cats that received sildenafil as part of their clinical management. Medical records and pharmacy databases were searched for cats that received sildenafil for ≥24 h between 2009 and 2021, and data were collected from medical records. Fifty-five cats received sildenafil for ≥24 h and were included in the study: 43 with primary cardiac disease (acquired, n = 28; congenital, n = 15) and 12 with primary respiratory disease. Side effects possibly attributed to sildenafil were identified in two cats (systemic hypotension, n = 1; polydipsia, n = 1), and sildenafil was discontinued in the cat with hypotension. Sildenafil was discontinued in an additional three cats due to a lack of improvement in clinical signs. No cat was documented to develop worsening pulmonary edema within 72 h of starting sildenafil. Median duration of sildenafil administration was 87 days (range, 2-2362 days). Sildenafil administration in cats appeared to be generally well-tolerated. Studies are needed to determine whether sildenafil administration to cats with cardiopulmonary disease improves the quality of life or survival times.

Complex Tetralogy of Fallot in an Acyanotic Adult Dog

•TOF with PA hypoplasia can be diagnosed in adult dogs. •MAPCAs were suspected on the basis of TTE detection of collateral vessels. •Acyanosis in this dog was attributed to multiple sources of pulmonary blood flow. •Augmented reality can provide unique imaging capabilities for complex heart defects.

Key considerations in the approach to congenital heart disease in dogs and cats

Congenital heart disease is an important subset of all cardiovascular disease in dogs and cats that is present at birth and most often detected in young animals but can be diagnosed in adulthood. The range of abnormalities that can occur during development of the heart is vast incorporating simple and complex defects, varying degrees of severity and clinical presentations that include heart failure and cyanosis. While some defects do not result in morbidity in an individual animal, others cause severe clinical signs and death at a young age. Advances in imaging and expanding treatment options offer increasingly more possibilities in the diagnosis and management of congenital heart disease which is the focus of this review. The objective is to provide a broad overview of current practice and highlight key aspects to guide practitioners in their approach to congenital heart disease diagnosis and knowledge of available treatment options.

Persistent truncus arteriosus with an anomalous coronary artery in a cat

A 6-month-old, female, domestic shorthair cat weighing 1.8 kg presented with cardiomegaly seen on radiographs taken at a primary care veterinary center. Echocardiography revealed a single enlarged vessel overriding a ventricular septal defect and severe hypertrophy of the right ventricular free wall. There was no evidence of a pulmonary arterial trunk originating from the heart. The blood flow through the ventricular septal defect exhibited right-to-left shunting. The cat suddenly experienced dyspnea and died at home, and a postmortem examination was performed. A single large vessel was noted leaving the heart, from which the right and left pulmonary arteries arose separately; a main pulmonary artery was absent. There was only one single anomalous coronary ostium that arose from the brachiocephalic artery and divided into two branches. The walls of the extracardiac coronary artery were thick, but neither infarcts nor narrowing was observed within the coronary arteries. There were no abnormalities in the intracardiac coronary artery. These findings revealed a persistent truncus arteriosus with an anomalous coronary artery. A combination of these anomalies might have contributed to the early death of the cat.

Common arterial trunk in a cat: a high-resolution morphological analysis with micro-computed tomography

A 6-month-old female cat presented with respiratory distress. Physical examination showed a grade 5/6 holosystolic murmur with prominent precordial impulse over the left cranial chest wall. Echocardiography revealed bilateral hypertrophy of the ventricular walls, a dilated ascending aorta overriding the interventricular septum, a membranous ventricular septal defect and no obvious pulmonary trunk or pulmonary artery branches. Turbulent blood flow was detected around the ventricular septal defect and ascending aorta. Follow-up assessment, 12 months later, revealed marked and progressive biatrial dilation and biventricular hypertrophy. Four months after that, the cat died of severe congestive heart failure. To make a definitive postmortem diagnosis, we performed contrast enhanced micro-computed tomography (CT) on the ex vivo heart with micron-scale spatial resolution imaging and three-dimensional reconstruction. Micro-computed tomography analysis confirmed a common arterial trunk that bifurcated into the left pulmonary artery and aorta 5-mm distally from the truncal valve. The pulmonary trunk was absent. Slightly distal to the first branching, the common arterial trunk further branched into the right pulmonary artery and ascending aorta, indicating the aortic dominant form. Although CT angiography would be a preferred imaging modality for living animals, micro-computed tomography is a valuable tool for the ex vivo diagnosis of complex cardiac anomaly, such as presented in this cat.