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The objective of this project was to determine radiographic vertebral heart sizes and electrocardiographic (ECG) and echocardiographic measurements in healthy anesthetized maned wolves (Chrysocyon brachyurus). The wolves, housed at the White Oak Conservation and Smithsonian National Zoo Conservation and Research Centers, were being anesthetized for annual examinations. Cardiac auscultation, thoracic radiographs, a standard 6-lead ECG, and echocardiography were performed on the wolves while they were under general anesthesia. Thirteen maned wolves were evaluated: five males and eight females. Mean age was 6.4 +/- 4.4 years (range, 2-13 years). Mean weight was 26 +/- 2.95 kg (range, 22-32 kg). Low-grade systolic murmurs were auscultated in three of 13 maned wolves. Evaluation of ECGs revealed a sinus rhythm, with a QRS morphology, and mean electrical axis similar to domestic canines. Radiographic evaluation revealed a mean vertebral heart size of 8.27 +/- 0.48 (range, 7.9-8.6). In addition, the cardiac silhouette was seen to elongate, with an increase in sternal contact in older wolves. Echocardiography showed that mitral valve degenerative changes and insufficiency is likely common in older wolves. Visualization of physiologic regurgitation across the mitral and pulmonary valves was common in wolves of all ages. Left ventricular measurements were similar to those reported for healthy dogs, and several variables correlated well with body weight. Two wolves were found to have one to three heartworms in the right pulmonary artery, and degenerative mitral valve disease was determined in maned wolves older than 6 years of age. All of the wolves in this study were on heartworm preventative and tested negative for heartworm antigen at their annual examinations. The results of this study provide reference information for use in the cardiac evaluation of anesthetized maned wolves.

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This study investigated the feasibility of using a modified transesophageal atrial pacing system for dogs requiring temporary ventricular pacing. Atrial pacing was readily achieved in the one dog studied, but it caused considerable diaphragmatic movement. Ventricular pacing could not be achieved at any lead configuration or energy stimulation. While transesophageal cardiac pacing was a safe procedure, the large variation in the chest anatomy of dogs requires further study to explore this model as a substitute for transvenous or transthoracic ventricular pacing.

A n 18-year-old Thoroughbred breeding stallion was referred to the Veterinary Medical Center at the University of Florida for evaluation and treatment of respiratory distress and fever. The stallion had been housed on pasture since the conclusion of the breeding season, 2 months before presentation. Two days before presentation, the stallion became lethargic and had bilateral mucopurulent nasal discharge. Examination by the referring veterinarian before referral identified pyrexia, bilateral mucoid nasal discharge, abnormal lung sounds, and a cardiac murmur. A murmur had not been noted during routine examination 8 months earlier.On physical examination, the animal was tachycardic (76 beats/min [bpm]) with a regular heart rhythm, tachypneic (40 breaths/min), and had an increased body temperature of 39.21C. The animal weighed 500 kg with a body condition score of 3/9. Auscultation of the lungs disclosed bilateral crackles and wheezes. Auscultation of the heart identified a grade IV/VI diastolic murmur in the left fourth intercostal space, a grade III/VI holosystolic murmur in the left 5th intercostal space, and a grade III/ VI continuous murmur over the right 3rd to 4th intercostal space. No jugular pulses or peripheral edema were noted. Peripheral pulses were synchronous but bounding. Hematologic abnormalities included leukocytosis (22,910/mL; reference range, 5,500-12,100/mL) with neutrophilia (21,000/mL; reference range, 2,200-8,100/mL) and a mild left shift (band neutrophils, 230/mL; reference range, 0-100/mL). Fibrinogen concentration (300 mg/dL; reference range, 100-400 mg/dL) and cardiac troponin I (o0.05 ng/mL; reference range, 0.00-0.14 ng/mL) were normal.Thoracic ultrasonography identified diffuse bilateral pleural irregularities and minimal pleural effusion. Thoracic radiographs identified a pronounced interstitial pattern with diffuse, ill-defined pulmonary nodules. The pulmonary vasculature and cardiac silhouette were partially obscured. A tracheobronchial aspirate was performed, and cytologic examination of the fluid disclosed nonseptic neutrophilic inflammation. Bacterial and fungal cultures subsequently yielded no growth. Cytologic examination of bronchoalveolar lavage (BAL) fluid indicated marked goblet cell hyperplasia and mild nonseptic mixed inflammation. Radiographic and clinical pathologic findings were suggestive of equine multinodular pulmonary fibrosis (EMPF). Recommended diagnostics included histopathologic analysis of lung biopsy specimens, and polymerase chain reaction (PCR) analysis of lung tissue and BAL cells for equine herpes virus (EHV)-2 and EHV-5. Further testing was declined by the owner because of the poor prognosis associated with severe respiratory and cardiac disease. ). Fractional shortening was increased (48%; reference range, 32-45%). The aortic and mitral valves both were severely thickened and there was prolapse of the right coronary cusp of the aortic valve. There was an 8 mm fistula between the right coronary sinus and the right ventricle just below the tricuspid valv...