Cardiomyopathy Introduction - OmniMedicalSearch.com

Conditions & Diseases: Cardiovascular System

Cardiomyopathy

Introduction & Types

Cardiomyopathy is progressive weakening of the heart muscle or change in the heart muscle structure leading to thickening, stiffening and abnormal enlargement of the heart with impairment to pumping and/or receiving blood, causing arrhythmia and at times heart failure (1), (2) & (3). In the United States presently, about 3 million people live with the disease and approximately 400,000 are diagnosed every year. Many people die of heart failure, which is a most common manifestation of cardiomyopathy. About a quarter million deaths are due to cardiomyopathy (4).

Types of Cardiomyopathy
Structurally, a human heart consists of four chambers, the upper two chambers called the atria (left and right) and the lower two chambers called the ventricles (left and right).

The different types of cardiomyopathies include:

1. Dilated Cardiomyopathy: In dilated cardiomyopathy, the muscles of the heart begin to dilate or stretch which causes the heart’s walls to become thinner. This dilation starts in the left ventricle leading to enlargement of inner space of the ventricle, which may gradually spread to right ventricle and in the worst case even to the atria. The dilation of chambers results in inefficient pumping of blood by heart, weakening of heart and ultimately leading to heart failure (5). Dilated cardiomyopathy includes many conditions:

Ischemic Cardiomyopathy: Ischemic cardiomyopathy occurs due to a blocking of the arteries with plaque (plaque is progressive build up of fatty substances, cholesterol, cellular waste products, calcium and fibrin in the arteries) leading to oxygen deficiency to heart’s muscles tissue. This is a common cause of congestive heart failure (6).
Idiopathic Cardiomyopathy: When the exact cause is not known it is called as idiopathic cardiomyopathy (7).
Hypertensive Cardiomyopathy: Hypertensive cardiomyopathy is caused by high blood pressure. When myocardial systolic function is depressed out of proportion due to an increase in wall stress, the condition is called hypertensive cardiomyopathy (1) & (8).
Infectious Cardiomyopathy: Cardiomyopathy in people suffering from infections such as AIDS, Lyme disease, chagas disease, viral myocarditis and other infections are called as Infectious Cardiomyopathy (3).
Alcoholic Cardiomyopathy: Excessive habitual use of alcohol leads to weakening of the heart muscle making the heart inefficient in pumping blood (9).
Toxic Cardiomyopathy: This type is caused due to usage of cocaine and some chemotherapy drugs.
Peripartum Cardiomyopathy: This type of cardiomyopathy appears in women during the last trimester of pregnancy or post childbirth.
Tachycardia Mediated Cardiomyopathy: This type occurs in people having an unusually fast heart rate (3).

2. Hypertrophic Cardiomyopathy: Excessive thickening of the heart muscle without an obvious cause (Heart muscles may thicken due to hypertension or prolonged athletic training) leads to Hypertrophic Cardiomyopathy. This condition is also called as Hypertrophic Obstructive Cardiomyopathy (HOCM), Idiopathic Hypertrophic Sub-Aortic Stenosis (IHSS) and Muscular Sub-Aortic Stenosis (10).

3.Restrictive Cardiomyopathy: In this type, the heart’s muscles become stiff and rigid due to replacement of the normal heart muscle with abnormal tissue such as scar tissue. The ventricles lack relaxation and thus cannot expand to fill with blood causing the atria to become enlarged (2).

4. Arrhythmogenic Right Ventricular Dysplasia (ARVD): This is a very rare inherited heart muscle disorder, wherein a damaged or dead heart muscle in the right ventricle is gradually replaced with scar tissue and fat leading to problems in heart’s electrical signaling and arrhythmias. It is also called as Arrhythmogenic Right Ventricular Cardiomyopathy (ARVC) (5) & (11).

Article by Kona Vishnu, MS
Medical Writer,
OmniMedicalSearch.com