Heart disease in cats is often seen as hopeless, but alternative treatments such as nutritional therapy, herbs, and even medicinal leeches may offer some promise.

Heart disease and blood clots in cats are often regarded as hopeless disorders for which little or nothing can be done. With some proactive thinking, however, and the integration of a variety of alternative therapies, cats prone to cardiomyopathy and thromboembolic disease may have a better outlook.


There are several cardiomyopathies, but the two seen most often in practice are the dilated and hypertrophic forms.

  1. Dilated cardiomyopathy has all but disappeared with the recognition of taurine deficiency as the cause, and the subsequent required addition of this important amino acid to all processed cat foods.
  2. Hypertrophic cardiomyopathy persists as the most diagnosed form, especially secondary to feline hyperthyroidism. A common sequela to this is the all-too-familiar sudden onset of “saddle” thrombus or aortic thromboembolism, which can be excruciatingly painful and paralyze a kitty in one day.

Client education and proactive care are critical to preventing or at least delaying the onset of these disorders. Cat parents have become increasingly wary of processed cat foods, given all the recalls and social media shares about inadequate nutrition and potentially toxic ingredients in many commercial brands. This has led to a resurgence of home cooking. It is important that veterinarians question what a client is feeding their cat and counsel them regarding balance and adequate amounts of necessary nutrients. Many cat parents may not realize that cooking meat destroys taurine, and that its deficiency is a cause of dilated cardiomyopathy. Those who home prepare their cats’ food must give them complete, raw, species-appropriate diets; if they are heating the meat, they must add taurine and other missing nutrients.

Today’s post-COVID veterinarians must regain the trust of pet parents who have become reluctant to seek timely veterinary care. We must also shift focus away from over-vaccinating and instead emphasize the importance of annual wellness exams and bloodwork, especially in our aging cat population.


Cats eight years or older should receive annual blood work screening that includes a TT4 and a proBNP. Explain to clients that cats who are eating great but losing weight are at risk for feline hyperthyroidism. Diagnosis can be delayed when a chubby cat who is dieting and losing weight has concurrent thyroid disease. When a cat’s thyroid disease goes undetected, they can develop secondary hypertrophic cardiomyopathy (HCM).

Veterinarians must explain to cat parents that not hearing a murmur with a stethoscope does not mean heart function is okay.

A proBNP is a great screening tool. If it is negative, it provides peace of mind. If it is positive, it creates the impetus to recommend an echocardiogram. Don’t let one of your feline patients succumb to sudden death due to undetected cardiomyopathy!


Felines with elevated TT4 and/or proBNP need follow-ups and monitoring. Many of these cats also have hidden kidney disease, which becomes unmasked with the treatment of hyperthyroidism. Balancing TT4 with BUN/creatinine/SDMA using methimazole can be like walking a tightrope. Not enough methimazole to bring down TT4 causes secondary heart disease; too much allows kidney tests to elevate and leads to decreased appetite.

Where there are thyroid, heart, and kidney issues, there may also be blood pressure problems. So don’t forget to check that too! Undetected blood pressure problems can exacerbate kidney and heart issues; hypertension can also cause blindness in cats.

If you are having trouble regulating a cat’s TT4, or they are experiencing methimazole side effects of facial pruritus or bone marrow suppression, consider changing the type of thyroid medication you are using. In my hands, the Felimazole brand rarely causes side effects and is easy to administer. I have found compounded ear gel formulations to be extremely inconsistent in efficacy. Of course, inform cat owners that thyroidectomy and radioiodide treatment options also exist, but each has its pros and cons.

I have not seen herbals used alone to be effective as a sole treatment for full-blown hyperthyroidism; as an adjunct or for early intervention, however, they can be very helpful. Several commercial feline nutritional supplements combine glandular and herbal ingredients to support thyroid, kidney, liver, and cardiovascular health. Combination products can be great for kitties who do not appreciate a boatload of supplements added to their food or syringed into their mouths. Products that contain the organ of interest can be most beneficial and palatable.


  • Heart muscle is high in taurine, and should be fed as part of a commonsense prevention strategy for a cat’s entire life. Fresh organs can be presented in raw meals, or freeze-dried versions can be fed as meal toppers or treats. Cooking heart muscle destroys the taurine.
  • Beef heart contains complete protein with nine essential amino acids. It also contains peptides, which may improve heart contraction strength. I still get chills when I think about how much sense it makes to feed a fresh, prey-concept diet that includes organs to prevent and manage organ dysfunction in our carnivorous pets!
  • Beef heart is loaded with B vitamins. Excess B vitamins are expelled in the urine. Many veterinarians prescribe B12 injections for their aging feline patients. Obtaining these vitamins naturally in food can boost energy, and improve mentation, immune function, and normal cell division. B vitamins help maintain healthy blood pressure, and aid with the enzymatic reactions that keep a carnivore’s brain and heart clear of homocysteine, a potentially harmful by-product of protein metabolism.
  • The selenium in beef heart is critical for thyroid and immune function, and is preferable to the synthetic sodium selenite in most processed pet foods. Selenium helps in the cascade of nutrients that repair DNA.
  • Beef heart contains large quantities of the antioxidant coenzyme Q10. Antioxidants slow the aging process. This nutrient is commonly “prescribed” for heart and oral health.
  • Cats can also obtain antiviral immune-supportive zinc from eating heart muscle. Zinc impacts the destruction of damaged cells and protects the respiratory tract. The zinc from heart muscle is preferable to the laboratory-derived zinc proteinate, which is typically made from GMO soy and is a hidden source of glyphosate in processed pet foods.
  • Heart is loaded with iron, a building block of red blood cells that help deliver oxygen to the body’s tissues. A kitty low in iron will feel very tired. Again, a natural source is preferable to iron proteinate, the chelated iron found in kibble and canned foods (see sidebar on page 33). Even worse is the iron oxide used in super cheap animal feed.

Try to source heart muscle from organic, pasture-raised animals. Pasture-raised livestock is higher in healthy fats and many micronutrients. It’s also possible that the heart of a stressed animal is less desirable for consumption than the heart of a happy one.


  • Hawthorn berry is a well-known Western herbal that is nutritive to the heart and helps balance blood pressure. Like taurine and CoQ10, it is used in many feline heart supplements. Scientists say this Crataegus spp. has multiple effects on the cardiovascular system, including hypotensive activity via vasorelaxation from nitrous oxide stimulation; significant antioxidant activity; and tonic action on cardiac myocytes. Studies show that the whole herb is greater than the sum of its parts, and that it is very safe and can be combined with other cardiac medications. Standard Process Feline Cardiac Support contains bovine heart, hawthorn berry and more. Thorne Bio-Cardio contains taurine, CoQ10, hawthorn, etc.
  • Zhi Bai Di Huang Wan is a Chinese herbal with a positive reputation among TCVM practitioners as a formula for early intervention in hyperthyroid cats, and especially those with elevated kidney indicators.
  • Jing Tang Heart Qi Tonic can be used with early onset heart issues. It also seems to reduce the need for diuretics, and can improve quality of life and increase longevity even in cats developing pleural effusion associated with HCM. This can be very important for practitioners trying to avoid diuretics in cats with concurrent kidney issues. Heart failure is a Qi deficiency. The ingredients in Heart Qi Tonic possess TCVM properties and their physiologic effects on cardiovascular function have been validated by many studies.
  • Astragalus root tonifies Qi. It may decrease calcium overload-induced myocardial damage and improve heart function.
  • Codonopsis root also tonifies Qi. It can activate the GS-β ARcAMP-PKA signaling pathway and improve morphology of the heart muscle.
  • Poria sclerotium drains damp and strengthens the spleen.
  • Cassia bark warms Yang.
  • Schisandra fruit was shown in a human study to reduce blood pressure by inhibiting sympathetic nerves, leading to a decrease of heart preload and a reduction of myocyte ischemia.
  • Polygala root tonifies the heart.
  • Oriental arborvitae seed/Biota/Bai Zi Ren also tonifies the heart.
  • Sichuan lovage rhizome/Ligusticum/Chuan Xiong moves the blood. Lovage is a cousin to parsley, tastes like celery, and has diuretic effects. It is also a digestive aid.
  • Dong quai root nourishes the blood. Also called angelica, this herb contains coumarins, which cause blood thinning.
  • Chinese licorice cured root and rhizome tonifies Qi, harmonizes the formula and tastes good.


Due to the grave prognosis for feline aortic thromboembolism (FATE) or saddle thrombus, euthanasia without attempting treatment is chosen by cat owners 50% to 75% of the time. Cats with concurrent heart disease typically survive less than three months, and those without heart failure less than eight months.

Practitioners treat these patients with anticoagulant and antithrombotic medications, but the hind limb paralysis can be persistent and painful, and the clot can cause permanent tissue damage. A more useful, novel approach does exist but is rarely used because it involves maintaining a leech colony.


Hirudo medicinalis, or medicinal leeches, can be used to relieve the TCVM diagnosis of blood stagnation by moving blood. They are FDA approved as a medical device and have bacteriostatic and anesthetic properties. The protocol for saddle thrombus treatment includes shaving and wetting the fur on the medial thighs and applying the leeches at LIV-10 and SP-11. When a leech bites, hyaluronidase and collagenase enzymes digest the tissues and access the blood vessels. Dilation of vessels occurs by the action of histamine-like molecules. Platelet functions and coagulation decrease, and inflammatory reactions are suppressed. Practitioners use this method successfully in the human plastic surgery field, and leeches have also been used to manage ear hematomas in dogs.

Exploring the alternative approaches discussed in this article may help improve the prognosis of cats diagnosed with cardiomyopathy.


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