Search

A new technique for the treatment of certain types of cardiac arrhythmias was used in a 3-year-old dog that was evaluated for incessant supraventricular tachycardia (220 to 280 beats/min), which had been refractory to several treatment regimens. The mechanism of supraventricular tachycardia was atrioventricular (AV) reentry, using a dorsoseptal accessory pathway (AP) for retrograde ventriculoatrial conduction (concealed AP). With the dog under general anesthesia and with fluoroscopic monitoring, electrode catheters were introduced into the heart via peripheral vessels. Electrical recordings allowed localization of the accessory AV pathway. Programmed electrical stimulation was used to verify the function of the abnormal AV connection. At the atrial insertion site of the AP, 2 applications of radiofrequency current (45 V, 21.6 W) were delivered to the dorsoseptal right atrium (near the coronary sinus ostium), which eliminated AP conduction and AV reentrant tachycardia. The dog has remained free of tachycardia and has not required medication during more than 1 year of follow-up.

Ophthalmic nodular fasciitis in 5 dogs was often manifested as subconjunctival masses of variable growth rate. Each mass was raised, pink, and hyperemic. Five masses involved the bulbar conjunctiva, and 2 masses involved the eyelids. Local excision of each mass successfully resolved the condition.

Lipid infiltration of the corneal stroma, sclera, and uvea occurred in a 2-year-old cottontail rabbit that had been fed an all-milk diet for 20 months. Superficial keratectomy was performed on the left eye but the rabbit died. Histologically, lipid deposits were most extensive in the anterior corneal stroma and posterior iridal epithelium.

Conjunctival swab specimens were obtained from both eyes of 43 horses, 25 cows, 50 dogs, and 25 cats without keratitis or other ophthalmologic problems. Fungi were isolated from 95% of the horses, 100% of the cows, 22% of the dogs, and 40% of the cats. Aspergillus spp were isolated from 56% of the horses, 12% of the cows, 8% of the cats, and none of the dogs. Penicillium spp and Cladosporium spp were isolated ubiquitously. Collectively, 28 species from 209 isolants were identified.

In two cases of naturally occurring disseminated histoplasmosis, multifocal inflammatory lesions were seen in the posterior segment of the eyes. Histologic examination of both animals revealed lesions of active choroiditis (cat) and retinitis (dog) in association with numerous Histoplasma capsulatum.