Feline Hypertension – Diagnosis and Management
Speaker: Nathalie Dowgray
Reviewed by: Dr Philip Judge
Event Name: WSAVA World Congress 2024
Key Takeaways
Top Tips
Key Takeaways
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- Understanding Feline Hypertension:
- Feline hypertension, particularly in older cats, is a complex and incompletely understood condition.
- The pathophysiology involves various systems like the renin-angiotensin-aldosterone system and changes in kidney function, blood vessel resistance, and vascular tone.
- Types of Hypertension:
- Situational Hypertension: Caused by stress, anxiety, or pain, leading to a temporary increase in blood pressure, sometimes up to 75 mmHg above normal.
- Secondary Hypertension: Results from underlying conditions like chronic kidney disease or hyperthyroidism. Less commonly, diseases including diabetes mellitus, hyperadrenocorticism, pheochromocytoma, and obesity can also cause hypertension.
- Primary Hypertension: Occurs in about 20% of older cats, and is diagnosed when no underlying cause is found.
- Clinical Signs:
- Hypertension can lead to blindness (retinopathy, ocular haemorrhage), neurological signs, heart failure, and kidney damage. Ocular and CNS signs are particularly common.
- Neurological symptoms such as ataxia, seizures, or altered behavior may also indicate hypertension.
- Diagnosis:
- Hypertension is diagnosed by sustained systolic arterial blood pressure above 160 mmHg. Concerns start around 130-140 mmHg.
- Persistent hypertension, rather than transient spikes, is a key sign of true hypertension in cats.
- Management:
- Reducing stress in the clinic environment and using cat-friendly practices can help minimize situational hypertension.
- Long-term management involves controlling underlying conditions (secondary hypertension) and the use of antihypertensive medications.
- Amlodipine is the best first-line treatment, and may result in a 30-70 mm Hg decrease in systolic arterial blood pressure
- Telmisartin, an angiotensin receptor blocker, is a good 2nd line drug that produces a 20-25 mm Hg decrease in systolic arterial blood pressure.Â
- Monitoring:
- Monitor blood pressure decreases 7-10 days after commencement of treatment
- If still hypertensive, consider
- Add in a 2nd anti-hypertensive medication, such as telmisartan or benazepril
- Look for other disease – consider hyperaldosteronism, among other conditions
- Understanding Feline Hypertension:
Top Tips
- Reduce Stress in the Clinic: Minimize situational hypertension by adopting cat-friendly or fear-free handling techniques to reduce anxiety in cats.
- Train Your Patients Early: Start taking blood pressure measurements during routine visits when cats are young to make them comfortable with the process later in life.
- Look for Underlying Causes: If a cat has sustained hypertension, search for conditions like chronic kidney disease or hyperthyroidism before focusing solely on blood pressure management.
- Repeat Measurements: Take multiple blood pressure readings in a calm setting to ensure accuracy and reduce the impact of situational hypertension.
- Monitor for Hypertensive Signs: Be alert for target organ damage such as retinopathy, kidney injury, or neurological changes in hypertensive cats.
- Medications: start with amlodipine; add telmisartan or benazepril if blood pressure remains elevated; and look for a secondary cause.