Hypertrophic cardiomyopathy (HCM) is a form of heart disease that is characterized by concentric enlargement and thickening (hypertrophy), primarily of the walls of the left ventricle, which is one of the 4 chambers of the heart (left and right ventricles, left and right atrias). As the ventricular walls thicken, they become less flexible and increasingly rigid, causing increased resistance to filling and reducing the normal outflow of blood. HCM is common in cats and uncommon in dogs. However, it does occasionally occur in dogs.
Most authorities believe that there is a hereditary component to hypertrophic cardiomyopathy (HCM), although the exact nature of the genetic abnormality is not known. Several different disease processes may together lead to HCM. Whatever the underlying cause, animals with hypertrophic cardiomyopathy have an inherent defect in certain heart muscle cells that are primarily located within the walls of the left ventricle. The walls of the ventricle thicken and become stiffer than normal. This allows blood
Hypertrophic cardiomyopathy (HCM), which is the most common heart disease seen in cats, is not frequently seen in domestic dogs. When it does occur in dogs, it may not be accompanied by any noticeable symptoms and may only be detected incidentally during a routine veterinary check-up. This suggests that the dog probably is not suffering substantial discomfort or distress due to its condition. Of course, some dogs are particularly stoic and may be feeling poorly
Hypertrophic cardiomyopathy almost always involves stiffening and thickening of the walls of the left ventricle. To diagnose this disease, other potential causes of left ventricular thickening and rigidity must first be ruled out. This is called making a diagnosis on the basis of exclusion. The other conditions that can cause ventricular stiffness include hyperthyroidism, subaortic stenosis (SAS), acromegaly and systemic hypertension (high blood pressure). The best way to identify physical abnormalities in one or more
The goals of treating hypertrophic cardiomyopathy (HCM) are to reduce any fluid build-up around the heart and lungs (pleural effusion and pulmonary edema), stabilize the dog’s heart rhythms, relieve the dog’s discomfort and restore a good quality of life. A number of different pharmaceuticals are available to help manage hypertrophic cardiomyopathy. Drugs known as beta blockers, ACE inhibitors, vasodilators and calcium channel blockers can help to reduce or stabilize a dog’s heart rate and rhythm