Cardiomyopathy | |
---|---|
Opened left ventricle showing thickening, dilatation, and subendocardial fibrosis noticeable as increased whiteness of the inside of the heart. | |
Specialty | Cardiology |
Symptoms | |
Complications | |
Types | |
Causes | |
Treatment | Depends on type and symptoms[5] |
Frequency | 2.5 million with myocarditis (2015)[6] |
Deaths | 354,000 with myocarditis (2015)[7] |
Cardiomyopathy is a group of primary diseases of the heart muscle.[1] Early on there may be few or no symptoms.[1] As the disease worsens, shortness of breath, feeling tired, and swelling of the legs may occur, due to the onset of heart failure.[1] An irregular heart beat and fainting may occur.[1] Those affected are at an increased risk of sudden cardiac death.[2]
As of 2013, cardiomyopathies are defined as "disorders characterized by morphologically and functionally abnormal myocardium in the absence of any other disease that is sufficient, by itself, to cause the observed phenotype."[8][9] Types of cardiomyopathy include hypertrophic cardiomyopathy, dilated cardiomyopathy, restrictive cardiomyopathy, arrhythmogenic right ventricular dysplasia, and Takotsubo cardiomyopathy (broken heart syndrome).[3] In hypertrophic cardiomyopathy the heart muscle enlarges and thickens.[3] In dilated cardiomyopathy the ventricles enlarge and weaken.[3] In restrictive cardiomyopathy the ventricle stiffens.[3]
In many cases, the cause cannot be determined.[4] Hypertrophic cardiomyopathy is usually inherited, whereas dilated cardiomyopathy is inherited in about one third of cases.[4] Dilated cardiomyopathy may also result from alcohol, heavy metals, coronary artery disease, cocaine use, and viral infections.[4] Restrictive cardiomyopathy may be caused by amyloidosis, hemochromatosis, and some cancer treatments.[4] Broken heart syndrome is caused by extreme emotional or physical stress.[3]
Treatment depends on the type of cardiomyopathy and the severity of symptoms.[5] Treatments may include lifestyle changes, medications, or surgery.[5] Surgery may include a ventricular assist device or heart transplant.[5] In 2015 cardiomyopathy and myocarditis affected 2.5 million people.[6] Hypertrophic cardiomyopathy affects about 1 in 500 people while dilated cardiomyopathy affects 1 in 2,500.[3][10] They resulted in 354,000 deaths up from 294,000 in 1990.[7][11] Arrhythmogenic right ventricular dysplasia is more common in young people.[2]