FUNDUS EXAMINATION IN OLDER CATS Many older cats have elevated blood pressure and if left untreated, blindness can result. It is important to recogni
FUNDUS EXAMINATION IN OLDER CATS
Many older cats have elevated blood pressure and if left untreated, blindness can result. It is important to recognise and treat hypertension before it becomes clinical. Underlying causes of hypertension include renal disease and heart failure.
Always perform fundus examination and measure the blood pressure in older cats. We recommend annual checks of each of these in cats 10 years and over. Hypertension is diagnosed when the blood pressure is over 160mmHg.
Fundus examination in blind cats usually reveals retinal detachments and retinal and vitreal haemorrhages. Routine fundus examination in cats with mild hypertension may reveal small haemorrhages from the retinal arterioles, or greyish or brownish exudates from the choroid. Unlike in dogs, the feline fundus is quite uniform, so abnormalities should stand out easily.
If you see any changes, measure the blood pressure. In general, retinal changes are the earliest sign of hypertension in cats. Furthermore, hypertension is one of the earliest indicators of renal disease. Some of the hypertensive cats we see have normal blood tests initially but have early evidence of renal insufficiency 6 months later when checked.
Amlodipine is the best treatment for hypertension in cats. A starting dose of 1.25mg (1/4 of a 5mg tablet) once daily is recommended. Blood pressure should be rechecked 2 weeks later and the target is 150-160mmHg or less. Amlodipine is extremely well tolerated in cats and side effects are extremely rare. We have not had any cats become unwell on this drug.
