Cardiomyopathy

Cardiomyopathy
Classification and external resources
Opened left ventricle of heart shows a thickened, dilated left ventricle with subendocardial fibrosis manifested as increased whiteness of endocardium.
ICD-10	I42.0
ICD-9	425.4
DiseasesDB	2137
MedlinePlus	001105
MeSH	D009202

Cardiomyopathy, which literally means "heart muscle disease", is the deterioration of the function of the myocardium (i.e., the actual heart muscle) for any reason. People with cardiomyopathy are often at risk of arrhythmia or sudden cardiac death or both. Cardiomyopathy can often go undetected, making it especially dangerous to carriers of the disease.

Although in theory the term "cardiomyopathy" could apply to almost any disease affecting the heart, in practice it is usually reserved for "severe myocardial disease leading to heart failure". The most common form of cardiomyopathy is dilated cardiomyopathy.

Classification

Cardiomyopathies can be categorized as extrinsic or intrinsic.

• An extrinsic cardiomyopathy is a cardiomyopathy where the primary pathology is outside the myocardium itself. Most cardiomyopathies are extrinsic, because by far the most common cause of a cardiomyopathy is ischemia. The World Health Organization calls these specific cardiomyopathies:

• An intrinsic cardiomyopathy is defined as weakness in the muscle of the heart that is not due to an identifiable external cause. This definition was used to categorize previously idiopathic cardiomyopathies although specific external causes have since been identified for many. For example, alcoholism has been identified as a cause for some forms of dilated cardiomyopathy. To make a diagnosis of an intrinsic cardiomyopathy, significant coronary artery disease should be ruled out (amongst other things). The term intrinsic cardiomyopathy does not describe the specific etiology of weakened heart muscle. The intrinsic cardiomyopathies consist of a variety of disease states, each with their own causes. Many intrinsic cardiomyopathies now have identifiable external causes including drug and alcohol toxicity, certain infections (including Hepatitis C), and various genetic and idiopathic (i.e., unknown) causes.

It is also possible to classify cardiomyopathies functionally, as involving dilation, hypertrophy, or restriction.

Types

• Primary/intrinsic cardiomyopathies
  • Genetic
    • Hypertrophic cardiomyopathy (HCM or HOCM)
    • Arrhythmogenic right ventricular cardiomyopathy (ARVC)
    • Isolated ventricular non-compaction
    • Mitochondrial myopathy
  • Mixed
    • Dilated cardiomyopathy (DCM)
    • Restrictive cardiomyopathy (RCM)
  • Acquired
    • Takotsubo cardiomyopathy
    • Loeffler endocarditis

• Secondary/extrinsic cardiomyopathies
  • Metabolic/storage
    • amyloidosis
    • hemochromatosis
  • Inflammatory
    • Chagas disease
  • Endocrine
    • diabetic cardiomyopathy
    • hyperthyroidism
    • acromegaly
  • Toxicity
    • chemotherapy
    • Alcoholic cardiomyopathy
  • Neuromuscular
    • muscular dystrophy
  • Nutritional diseases
    • Obesity-associated cardiomyopathy
  • Other
    • "Ischemic cardiomyopathy" is a weakness in the muscle of the heart due to inadequate oxygen delivery to the myocardium with coronary artery disease being the most common cause. Not supported by current cardiomyopathies classification schemes.

Signs and symptoms

Symptoms and signs may mimic those of almost any form of heart disease. Chest pain is common. Mild myocarditis or cardiomyopathy is frequently asymptomatic; severe cases are associated with heart failure, arrhythmias, and systemic embolization. Manifestations of the underlying disease (e.g., Chagas' disease) may be prominent. Most patients with biopsy-proven myocarditis report a recent viral prodrome preceding cardiovascular symptoms.

EKG abnormalities are often present, although the changes are frequently nonspecific. A pattern characteristic of left ventricular hypertrophy may be present. Flat or inverted T waves are most common, often with low-voltage QRS complexes. Intraventricular conduction defects and bundle branch block, especially left bundle branch block, are also common. An echocardiogram is useful to detect wall motion abnormalities or a pericardial effusion. Chest radiographs can be normal or can show evidence of congestive heart failure with pulmonary edema or cardiomegaly.

Treatment

Treatment depends on the type of cardiomyopathy, but may include medication, implanted pacemakers, defibrillators, or ventricular assist devices (LVADs), or ablation. The goal of treatment is often symptom relief, and some patients may eventually require a heart transplant. Treatment of cardiomyopathy (and other heart diseases) using alternative methods such as stem cell therapy is commercially available but is not supported by convincing evidence. Due to the severity of the disease, treatment requires the use of numerous chemicals and drugs, which have to be taken for the rest of the patient's life.

Treatments and drugs The overall goals of treatment for cardiomyopathy are to manage your signs and symptoms, prevent your condition from worsening, and reduce your risk of complications. Treatment varies by which of the major types of cardiomyopathy you have.

Dilated cardiomyopathy If you're diagnosed with dilated cardiomyopathy, your doctor may recommend medications, surgically implanted devices or a combination of both. The medications you may be prescribed include:

Angiotensin-converting enzyme (ACE) inhibitors to improve your heart's pumping capability, such as enalapril (Vasotec), lisinopril (Zestril, Prinivil), ramipril (Altace) and captopril (Capoten). Angiotensin receptor blockers (ARBs) for those who can't take ACE inhibitors, such as losartan (Cozaar) and valsartan (Diovan). Beta blockers to improve heart function, such as carvedilol (Coreg) and metoprolol (Lopressor, Toprol XL). Digoxin (Lanoxin). This drug, also referred to as digitalis, increases the strength of your heart muscle contractions. It also tends to slow the heartbeat. Digoxin reduces heart failure symptoms and improves your ability to live with cardiomyopathy. Diuretics. Often called water pills, diuretics make you urinate more frequently and keep fluid from collecting in your body. Commonly prescribed diuretics for heart failure include bumetanide (Bumex) and furosemide (Lasix). The drugs also decrease fluid in your lungs, so you can breathe more easily. One diuretic, spironolactone (Aldactone), may also be helpful in treating scarring of your heart tissue. Another option for some people with dilated cardiomyopathy is a special pacemaker that coordinates the contractions between the left and right ventricles (biventricular pacing). In people who may be at risk of serious arrhythmias, drug therapy or an implantable cardioverter-defibrillator (ICD) may be options. An ICD is a small device — about the size of a box of matches — implanted in your chest to continuously monitor your heart rhythm and deliver electrical shocks when needed to control abnormal, rapid heartbeats. The device can also work as a pacemaker.

Hypertrophic cardiomyopathy Your doctor may recommend beta blockers to relax your heart, slow its pumping action and stabilize its rhythm. These medications include Lopressor or calcium channel blockers, such as verapamil (Calan, Isoptin). Medications are often the preferred treatment for hypertrophic cardiomyopathy.

If medications don't work, you may need surgery or a medical device to treat your condition. Options include:

Septal myectomy. This is an open-heart operation in which the surgeon removes part of the thickened, overgrown heart muscle wall (septum) that separates the two bottom heart chambers (ventricles). Removing part of this overgrown muscle improves blood flow and reduces mitral regurgitation. Myectomy is used if medications don't relieve symptoms. Most people who have symptoms and undergo myectomy have no further symptoms. This type of surgery is available only in medical centers that specialize in the treatment of hypertrophic cardiomyopathy. Septal ablation. Also called septal alcohol ablation, this is a treatment in which a small portion of the thickened heart muscle is destroyed by injecting alcohol through a catheter into the artery supplying blood to it. There are possible complications with this procedure, including heart block — a disruption of the heart's electrical system — which requires implantation of a pacemaker. The long-term success of this procedure isn't yet known, but it's becoming more commonly used. Pacemaker implantation. A pacemaker is a small electronic device inserted under your skin that sends electrical signals to your heart to monitor and regulate your heartbeat. Surgery to implant the pacemaker is usually performed during local anesthesia and typically takes less than three hours. Pacemaker implantation is generally not as effective as surgical options, but it's sometimes used in older people who want to avoid more invasive procedures. Implantable cardioverter-defibrillator (ICD). This is a pager-sized device implanted in your chest like a pacemaker. An ICD continuously monitors your heartbeat. If a life-threatening arrhythmia occurs, the ICD delivers precisely calibrated electrical shocks to restore a normal heart rhythm. A small number of people with hypertrophic cardiomyopathy are at risk of sudden cardiac death because of abnormal heart rhythms. In these high-risk individuals, many doctors recommend the implantation of an ICD. Restrictive cardiomyopathy Treatment for restrictive cardiomyopathy focuses on improving symptoms. Your doctor will recommend you pay careful attention to your salt and water intake and monitor your weight daily. Your doctor may also recommend you take diuretics if sodium and water retention becomes a problem. You may be prescribed medications to lower your blood pressure and control fast or irregular heart rhythms.

Many of the medications that doctors prescribe for cardiomyopathy may have side effects. Be sure to discuss these possible side effects with your doctor before taking any of these drugs.

Heart transplant If you have severe cardiomyopathy and medications can't control your symptoms, a heart transplant may be an option. Because of the shortage of donor hearts, even people who are critically ill may have a long wait before having a heart transplant. In some cases, a mechanical heart assist device can help critically ill people as they wait for an appropriately matched donor. These devices, known as ventricular assist devices (VADs), can help blood circulate through your heart for months, or even years. A VAD may allow you to live outside the hospital while you wait. In some people who aren't candidates for a heart transplant, VAD therapy could be a long-term treatment option.

Prevention In most cases you can't prevent cardiomyopathy. Let your doctor know if you have a family history of the condition. If cardiomyopathy is diagnosed early, treatments may prevent the disease from worsening.

You can help reduce your chance of heart failure by avoiding some of the conditions that can contribute to a weak heart, including the abuse of alcohol or cocaine, or not getting enough vitamins and minerals. Controlling high blood pressure with diet and exercise also prevents many people from developing heart failure later in life.

Lifestyle and home remedies Your doctor may recommend adopting the following lifestyle changes to help you manage cardiomyopathy:

Quit smoking. Lose excess weight. Eat a low-salt diet (less than 2,300 milligrams a day). Get modest exercise, after discussing with your doctor the most appropriate program of physical activity. Eliminate or minimize the amount of alcohol you drink. Specific recommendations will depend on the type of cardiomyopathy you have.

References

http://www.bing.com/health/article/mayo-MADS00519/Cardiomyopathy?q=cardiomyopathy&qpvt=cardio+myopothy

External links

• Cardiomyopathy at the Open Directory Project

http://www.bing.com/health/article/mayo-MADS00519/Cardiomyopathy?q=cardiomyopathy&qpvt=cardio+myopothy