Familial cardiomyopathy (inherited heart disease) in Norwegian Forest cats
A study published in the Journal of Feline Medicine and Surgery with the title of the title to this article, states that "Pedigree data analysis of 871 NFCs was supportive of a familial cardiomyopathy in this breed."
|NFC. Image: quatre mains|
In other words, this breed like some other breeds in the cat fancy has this devastating disease within its breeding lines leading to the inheritance of this heart disease in many Norwegian Forest cats.
The study states that the breed is "often listed as a breed predisposed to cardiomyopathy". They wanted to describe the characteristics of the disease in this breed. They examined 53 NFCs.
They found no murmur or left ventricle outflow tract obstruction in any of the screen cats. They found mild left-ventricular hypertrophy was present in 13 out of the 53 cats, representing 25%. The left ventricle is one of four heart chambers. It receives oxygenated blood from the left atrium and pumps it into the systemic circulation via the aorta. The word "hypertrophy" means the enlargement of an organ which in this case refers to the left ventricle chamber.
They conducted pathology tests and histopathological sections on eight of the cats. "Histopathological sections" refers to examining slices of tissue under the microscope. Six of these cats had died of a cardiac cause i.e. a heart disease.
In 7 out of 8 of the cats they detected myocyte hypertrophy (hypertrophy of a muscle cell known as the myocyte), myofiber disarray (this describes a non-parallel arrangement of cardiac muscle cells indicating that they are in disarray), and interstitial fibrosis which contributes to left ventricle dysfunction leading to a development of heart failure. It is a hallmark of several cardiac diseases which is linked to progression of heart failure.
In the same cats they found endomyocardial fibrosis which is "suggestive of restrictive cardiomyopathy". Interestingly, endomyocardial fibrosis is, in humans, a disease of rural poverty. The word "fibrosis" means a thickening or scarring of heart tissue in this instance.
Interestingly, also, my book on medical and inherited diseases of purebred cats does not list familial cardiomyopathy as one of those diseases for this cat breed. The book was published some time ago in 1992 and therefore this information has come to light since.
Or perhaps the breeding of the Norwegian Forest cat has deteriorated over the years to the point where this is an inherited disease and whereas it might not have been in the past.