Veterinary Clinics of North America: Food Animal Practice
Camelid Cardiology
Section snippets
Evaluation of the patient suspect for cardiac disease
The cardiovascular system in lamoids shares many anatomic and functional similarities with other veterinary species; hence, the approach to a camelid suspect for cardiac disease is similar to what is routinely performed in other large animal species. Obtaining a thorough history is always instrumental in diagnosing medical conditions. Although definitive data are not available, congenital heart defects always carry the potential for heritability; therefore, collecting a family history might
Physical examination
A full medical history should be followed by a complete physical examination. This section focuses on the cardiovascular examination (more general information on physical diagnosis of lamoids is provided elsewhere in this issue). Inspection of the jugular veins has the potential to provide the clinician with information on the central venous pressure and filling conditions of the right heart and represents an important step in the diagnosis of right-sided CHF. It is unfortunate that jugular
ECG
The resting, surface ECG allows the evaluation of heart rate, rhythm, and conduction patterns and is most indicated in the setting of an auscultable or suspected arrhythmia. Techniques and normal reference values for alpacas and llamas have been described in the literature.20, 21, 22 A 6-, 9-, or 12-lead ECG is performed optimally with the patient in right lateral recumbency; however, this positioning can usually be accomplished only in young (<6 months) animals. Multiple-lead ECGs can be
Thoracic radiography
Thoracic radiography provides a valuable assessment of the patient that has suspected or confirmed cardiac or respiratory disease and a screening tool for patients presenting with nonspecific clinical findings. Adult unsedated South American camelids can be imaged in a standing position, and standard radiographic studies are limited to the lateral view. If sagittal views dorsoventral or ventrodorsal are to be obtained, deep sedation or anesthesia is frequently necessary. Crias can be imaged on
Echocardiography
Two-dimensional echocardiography with Doppler is the preferred diagnostic test for most camelids that have suspected heart disease. The echocardiographic study allows for precise determination of cardiac size, structure, and function, while displaying and quantifying intracardiac flow disturbances. In adult animals, it is easiest to perform the echocardiogram on a standing patient; in some cases, mild sedation may be required. Crias, typically up to 4 to 6 months of age, can be better imaged in
Congenital Heart Diseases
CHDs refer to a group of diverse pathologic conditions that affect the cardiovascular system as a result of abnormal or arrested embryologic development of the evolving heart. As a consequence, morphologic abnormalities, functional abnormalities, or both are present at birth or develop shortly after, which can cause morbidity and mortality in the affected individual. Some, if not most, CHDs are hypothesized or proven to be heritable in other species, making the diagnosis of these conditions
Summary
Cardiovascular disorders, although not thoroughly described in the literature, are frequently diagnosed in South American camelids, causing morbidity, mortality, and loss of production. Definitive confirmation concerning the heritability of cardiac defects in these species is lacking; however, this potential exists and should be taken into account when counseling breeders and owners. This article describes the diagnosis and treatment of cardiovascular diseases in llamas and alpacas and reviews
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Role of computed tomography angiography in the differentiation of feline truncus arteriosus communis from pulmonary atresia with ventricular septal defect
2017, Journal of Veterinary CardiologyCitation Excerpt :Defects such as TA, PA-VSD, tetralogy of Fallot, double outlet ventricles, and transposition complexes are rare forms of congenital heart disease resulting from abnormal partitioning of the cardiac outflow tracts. Limited reports exist in the veterinary literature describing cases of TA as well as PA-VSD [4–12]. These defects have been historically categorized as conotruncal defects [6]; as they are lesions in proximate relationship to the “conus”, the muscular infundibulum that supports the semilunar valves, and the “truncus”, the embryologic structure that divides to form the arterial trunks (pulmonary and aortic).
Cardiac-gated computed tomography angiography in three alpacas with complex congenital heart disease
2016, Journal of Veterinary CardiologyCitation Excerpt :Complex congenital abnormalities involving conotruncal septation and rotation appear to occur frequently in camelids. The prevalence of CHDs in alpacas submitted to the Oregon State University Veterinary Diagnostic Laboratory for necropsy was 1.5% (3/195) during the referral period of the three cases presented here (2011–2014), which is similar to that reported in the literature.2,4 The three cases are illustrative of some of the complex congenital defects involving the great vessels in alpacas and highlight the utility of contrast-enhanced CT in their diagnosis in conjunction with echocardiography and blood work.
Congenital isolated cleft mitral valve leaflet and apical muscular ventricular septal defect in a Holstein calf
2015, Journal of Veterinary CardiologyCitation Excerpt :A single case report describes a muscular VSD in a yak calf.15 Conversely, muscular septal defects are commonly observed in camelids.16 The more common membranous septal defect stems from a failure of fusion between the endocardial cushions and the muscular ventricular septum, leading to a persistence of the interventricular foramen.
Ventricular septal defect and double-chambered right ventricle in an alpaca
2015, Journal of Veterinary CardiologyCitation Excerpt :South American camelids do not appear to be at greater risk of congenital cardiac defects than other veterinary species,4 however, they seem to have a predisposition for complex congenital heart malformations (CHM).
Thoracic Imaging and Respiratory Surgery
2014, Llama and Alpaca Care: Medicine, Surgery, Reproduction, Nutrition, and Herd HealthImportant Causes of Neonatal Seizures
2014, Llama and Alpaca Care: Medicine, Surgery, Reproduction, Nutrition, and Herd Health