Digoxin has been long known to have prominent effects on congestive heart failures. There are few papers, however, reporting on the clinical effects of long-term administration of digoxin on non-anesthetized animals. This study was done to confirm the effectiveness of continual administration of digoxin on hemodynamics in clinically healthy dogs and mitral-valve-regurgitation-model (MR) dogs, both in a non-anesthetized condition. In all dogs, heart rates, blood pressure, and myocardial functions were examined periodically, before and during two-week administration, and after discontinuation of digoxin. In normal dogs, stroke volume (SV), cardiac output (CO), and cardiac index (CI) were also measured. The results from normal dogs are as follows. Digoxin was found to lower heart rates with statistical significance. It also lowered diastolic and mean blood pressure with statistical significance, with no changes in systolic blood pressure, which differs from the results of acute dosing with digoxin. Digoxin enhanced myocardial functions and SV, but decreased CO and CI, which suggested that digoxin mainly lowered heart rates. Continuous dosing with digoxin resulted in lower heart rates and blood pressure and increased SV. This means that digoxin enhanced cardiac function. In MR dogs, which we consider as being in an early compensatory stage of mitral insufficiency, digoxin lessened heart rates and blood pressure with unchanged pulse pressure and moderate increase of myocardial functions. Compared with normal dogs, the MR dogs showed no remarkable differences, except a slow recovery of diastolic pressure, The present study revealed that continuous administration of digoxin has statistically significant effects on hemodynamics of dogs in an early compnensatory stage of mitral insufficiency as well as in normal dogs.
Differences between two groups of cats with diabetes mellitus with and without ketouria were reviewed in 15 cases. Six cats with ketouria showed high levels of total serum billirubin, and low levels of electrolytes and phosphates, although there were no obvious differences between the two groups in total serum cholesterol, blood urea nitrogen (BUN), and creatinine. Two cats out of six with ketouria died within two months in spite of aggressive treatment. In the other four cases, insulin therapy improved the general conditions of the animals. One of them had a breast tumor, and another had been injected with some medicine, which was surmised to be a steroid, three days before in another hospital. These two cats needed insulin therapy, for only several days after their complications had been cleared up. Among the group without ketouria, two cats gradually became free of the need for insulin, after being cured of otitis media in the one case, and loose, bloody stool in the other. Therefore, it is considered that not only insulin therapy and transfusion therapy but also supportive treatment for concomitant diseases or troubles is important to obtain better prognosis for feline diabetes mellitus.
Eosinophilic keratitis in two cats is reported. In case one, topical treatment with 1% solution of cyclosporine in corn oil and oral treatment with prednisolone remarkably improved the symptoms, until the lesion regressed almost completely. When the medication was discontinued, the lesion recurred, but the same treatment was effective. In case two, treatmet with 0.02% dexamethasone and 0.1% prednisolone topically and prednisolone orally was not effective, resulting in only a partial regression of a thick mass granulation tissue.
An efficient surgical procedure for pulmonary valve stenosis in a miniature-type dog is reported. Congenital pulmonary valve stenosis was diagnosed by echocadiography and cardiac catheterization in a six-month-old female Yorkshire Terrier weighing 1.8kg. Systolic pressure gradient measured 113mmHg across the pulmonic valve with cardiac catheterization. Judging from the small cavity of the pulmonary artery, severity of the stenosis, and evidence of concomitant tricuspid valve regurgitation, a modified Brock technique, a direct transventricular valvuloplasty, was performed. The dog underwent the surgery with no signs of serious complications. Four months after surgery, cardiac catheterization showed that the dog was clinically normal, and the systolic pressure gradient had dropped to 67mmHg. These results indicate that this modified Brock technique is useful as a transventricular valvuloplasty in treating for pulmonary valve stenosis in miniature-type dogs.
An 11-year-old castrated Persian cat with abdominal distention and hyposthenea, and which had been anorexic for a few days, was brought to our hospital. The cat had received supportive therapy for two years for chronic renal failure and feline immunodeficiency virus (FIV) intection. Abdominal radiography and ultrasonography revealed a large cyst with a liquid pool in the rear hepatic margin. Apart form abnormal values related to chronic renal failure, the findings of hemogram and blood chemistry analysis were normal. When an abdominal median section was performed, a large dark-red cyst stemming from the left inner lobe of the liver was found. The cyst was filled with a large amount of liquid, with small masses scattered on the membrane surface of the cyst. This lobe was resected with the cyst. Histopathologically, the disease was dignosed as a cystic bile duct adenoma with cholangiocellular carcinoma. The cat was euthanized 23 months after lobectomy, since its chronic renal failure worsened, although liver function values were normal. Pathological examination showed the presence of a number of cystic bile duct adenomas in the liver, but no recurrence of the cholangiocellular carcinoma.