In Honor of
Princess Rose Zoya and all the kitties affected by HCM
Pictured is Zoya celebrating her first birthday, such a lovely creature!
HCM: Hypertrophic cardiomyopathy
Hypertrophic cardiomyopathy (HCM) is a disease of the myocardium (the muscle of the heart) in which a portion of the myocardium is hypertrophied (thickened) without any obvious cause. It is perhaps most well known as a leading cause of sudden cardiac death in young athletes. A cardiomyopathy is a primary disease that affects the muscle of the heart. With hypertrophic cardiomyopathy (HCM), the sarcomeres (contractile elements) in the heart increase in size, which results in the thickening of the heart muscle.
Feline hypertrophic cardiomyopathy (HCM) is the most common heart disease found in domestic cats, all breeds, not just the sphynx. It is generally a genetic disease and can happen at any time. The disease process and genetics are believed to be similar to the disease in humans. It is characterized by an abnormally thickened (hypertrophic) myocardium, the muscle that forms the heart wall.
Because of its increased thickness, the myocardium becomes stiffer and does not distend enough to allow complete, so a lower blood volume will be pumped into circulation after each heart beat eventually, the upper heart chambers (atria) dilate in response to the increased pressure in the lower chambers (ventricles).
Initially, the affected cat does not present any noticeable symptoms (compensatory phase). However, with time, the pressure may also increase in the left atrium and, subsequently, in the vessels that carry blood from the lungs to the left atrium. These vessels become engorged with blood and, eventually, fluid will leak from the vessels into the lungs (pulmonary edema) or chest cavity (pleural effusion). If fluid starts building up in the lungs or chest cavity, the cat starts breathing with difficulty and at a faster rate (usually more than 40-50 breaths per minute). This symptomatic phase of the disease is called “congestive heart failure” or simply CHF.
While medication is not commonly given to cats with HCM that have no clinical signs, it has been shown that an ACE inhibitor is beneficial when heart failure is present (at which time a diuretic is most beneficial). Diltiazem generally produces no demonstrable benefit and Atenolol is commonly administered when the systolic anterior motion of the mitral valve is present. Unfortunately, death can occur without any other signs present making the disease a difficult and sometimes a deadly one.
While there is no cure for HCM, early detection and regular echocardiograms are key to trying to ward off life-threatening problems. We proactively scan our cats regularly by a board certified cardiologist to ensure we are breeding healthy bloodlines. This is the best tool we have right now; however, it is no guarantee that the lines are completely free from HCM. We also look at pedigrees to help select the best cats for our breeding program as well as outcrossing often to vary the genetics.
How can you Help?
Please HCM scan your cat, it may prolong your cat's life. It will help me keep the strong bloodlines breeding that do not have HCM showing up in them and will help eliminate the continued breeding of week bloodlines that do have HCM showing.