HCM nutrition guide → now reorganised into The HCM Bible

No. In stages B1 and B2, excessive sodium restriction can activate the RAAS early and strain the kidneys, so moderate restriction (0.2 to 0.35 percent DM, 500 to 900 mg per 1000 kcal) is recommended. Once heart failure develops in stages C and D, strict restriction of 0.1 to 0.2 percent DM, or 200 to 500 mg per 1000 kcal, is needed to prevent edema and ascites.

Per CAVN, the recommended EPA plus DHA dose for cats with heart disease is 115 mg per kg of body weight, which is 345 mg for a 3 kg cat, 460 mg for 4 kg, and 575 mg for 5 kg. Cats cannot convert plant oils (ALA), so use a fish-based oil, and check the label since EPA and DHA content varies by product.

In the Freeman et al. (2020) study, a diet with starch restricted to 38.8 g per Mcal fed for 12 months significantly reduced ventricular wall thickness and IGF-1, and median left ventricular wall thickness returned to the normal range of 6 mm or less. It may be a strategy to slow progression especially in the subclinical stage (B1 to B2) before atrial enlargement, so discuss any diet change with your veterinarian.