Dilated cardiomyopathy

Related Terms

Amyloidosis, arrhythmia, arrhythmogenic right ventricular cardiomyopathy, arrhythmogenic right ventricular dysplasia, ARVC, ARVD, broken heart syndrome, CAD, cardiac resynchronization therapy, congestive heart failure, coronary artery disease, CRT, dilated cardiomyopathy, diuresis, endomyocardial fibrosis, familial hypertrophic cardiomyopathy, HCM, heart disease, heart failure, hypertrophic cardiomyopathy, ICD, implantable cardioverter-defibrillator, ischemic cardiomyopathy, myocardium, peripartum cardiomyopathy, postnatal cardiomyopathy, pregnancy-induced hypertension (preeclampsia), primary cardiomyopathy, restrictive cardiomyopathy, sarcoidosis, secondary cardiomyopathy, stress cardiomyopathy.

Background

Cardiomyopathy refers to several diseases that affect the myocardium (heart muscle) and are associated with mechanical and/or electrical dysfunction. In cardiomyopathy, abnormal heart function results from weakness or structural changes in the myocardium.
There are four main types of cardiomyopathy as defined by the American Heart Association (AHA): arrhythmogenic right ventricular cardiomyopathy, dilated cardiomyopathy, hypertrophic cardiomyopathy, and restrictive cardiomyopathy. They are then categorized into two groups: primary or secondary. Primary cardiomyopathies may be genetic (inherited) or acquired (develop the condition). Secondary cardiomyopathies result from an underlying condition such as diabetes, thyroid disorders, chronic alcohol consumption, infection, or drugs/toxins (e.g., heavy metals, anthracyclines, cocaine). Clinical presentation varies from asymptomatic (without symptoms) to sudden cardiac death.
Therapies for cardiomyopathy aim to reduce the symptoms of heart failure and the risk of complications such as arrhythmia (irregular heartbeat or abnormal heart rhythm). Treatments may involve drugs, implantable cardioverter-defibrillators (ICDs), or cardiac resynchronization therapy (CRT) to regulate the heartbeat and reduce the risk of fatal arrhythmias. In some cases, heart transplant may be necessary. General measures that may reduce mortality and prevent future occurrences of heart failure include controlling blood pressure and weight (through diet and exercise), reducing alcohol and sodium consumption, and quitting smoking.

Signs and symptoms

General: The symptoms of cardiomyopathy are similar to the symptoms commonly seen in heart failure, particularly congestion (backed up blood) caused by abnormal heart function. The symptoms of congestion include shortness of breath, fatigue, and swelling, particularly in the legs and feet. Other symptoms such as dizziness, lightheadedness, and fainting develop as the body tries to compensate for the heart's reduced pumping ability. As the heart beats faster, its muscle thickens, and the ventricles (pumping chamber) may stretch to accommodate more blood. Damage to the ventricles may cause them to pump irregularly, further reducing the efficient delivery of blood to the body.
Symptoms of congestive heart failure (CHF, a condition in which the heart cannot pump enough blood to meet the body's needs) include: a dry, hacking cough, especially when lying down; confusion, sleepiness, and disorientation may occur in older individuals; dizziness, fainting, fatigue, or weakness; fluid buildup (edema), especially in the legs, ankles, and feet; increased urination at night; nausea; abdominal swelling, tenderness, or pain; weight gain due to fluid buildup; weight loss as nausea causes a loss of appetite and as the body fails to absorb food well; rapid breathing, bluish skin, and feelings of restlessness, anxiety, and suffocation; shortness of breath and lung congestion as the blood backs up in the lungs; and wheezing and spasms of the airways similar to asthma.
In arrhythmogenic right ventricular cardiomyopathy (ARVC), symptoms of heart failure are less common than other forms of cardiomyopathy. Instead, tachycardia (fast heartbeat) and angina (chest pain) are typical symptoms.
Many cardiomyopathies present no obvious symptoms in early stages. Sometimes, sudden heart failure and/or death are the first symptoms of cardiomyopathy.

Diagnosis

General: Because the most common symptom of cardiomyopathy is heart failure, diagnosis of cardiomyopathy follows similar guidelines for evaluating heart failure. Physical examination, blood tests, electrocardiogram (ECG or EKG), echocardiogram, chest X-ray, magnetic resonance imaging (MRI), cardiac catheterization, stress test, and nuclear stress test are used to diagnose cardiomyopathy. These tests may also reveal structural defects in the heart muscle (myocardium) that are characteristic of cardiomyopathy.
Physical examination and medical history: During a physical examination, a doctor will look for underlying causes of the problem and assess heart function. A stethoscope is used to detect murmurs (abnormal heart sounds) that may indicate a leaky or narrowed valve and to detect fluid accumulation in the lungs. The doctor also looks for enlarged veins in the neck and for edema (swelling) in the legs, particularly the ankles, feet, and/or the abdomen.
A patient history may include information about risk factors, such as family medical history, past surgeries and medications, history of chest pain, high blood pressure (including treatments), heart attack, recent viral illness, or recent pregnancy.
Blood tests: Blood tests may include: blood cell counts to test for conditions such as anemia (low red blood cells); electrolyte levels, including sodium, potassium, and calcium; nutrient levels, such as vitamins and trace minerals; tests for kidney function, including blood urea nitrogen (BUN) and creatinine levels; and testing for homocysteine and/or C-reactive protein (CRP), both markers of inflammation and heart disease. Brain natriuretic peptide (BNP) is a test used to measure the amount of BNP hormone in the blood and also used to diagnose heart failure. Brain natriuretic peptide (BNP) is a hormone produced at higher levels by the failing heart muscle.
Electrocardiogram (ECG or EKG): An electrocardiogram (ECG or EKG) is a noninvasive test used to measure electrical activity in the heart. Electrical sensors called leads are attached to predetermined positions on the arms, legs, and chest to record electrical activity and help assess heart function. The heart's rhythm of contraction is controlled by the sinoatrial node (SA node), often called the pacemaker. Electrical impulses generated from the SA node spread through the heart via a nodal tissue pathway that coordinates the events leading to heart beat. This conduction system initiates and coordinates the muscular activity of the heart.
Echocardiogram: An echocardiogram, or echo, is an ultrasound examination of the heart that produces detailed images of the organ. It may be used to detect abnormalities in the structure of the heart and to measure the amount of blood ejected from the heart. During an echocardiogram, a microphone-like device (transducer) is used to transmit and receive ultrasonic waves that travel through the chest wall to the heart and are reflected back to the transducer. The reflected sound waves are translated into images of the heart, including the valves, chambers, and walls.
Echocardiogram also is used to measure the pressure change (gradient) between the left ventricle and the aorta (largest artery of the body), to assess thickening of the walls of the heart, to evaluate pumping function, and to measure the amount of dilation (increased diameter) of the left ventricle.
Chest X-ray, magnetic resonance imaging (MRI), or computerized tomography (CT) scan: X-rays, MRIs, and CT scans are useful in visualizing structural defects in the heart that cause cardiomyopathy. These defects include enlargement of the heart or thickening of the myocardium.
Cardiac catheterization: Cardiac catheterization may be performed in individuals with angina and in those with a history of heart attack to determine if coronary heart disease (CHD) is causing heart failure. Cardiac catheterization with angiograms (x-ray images of blood vessels) of the coronary arteries and the left ventricle can be used to monitor heart function.
Cardiac catheterization involves injecting a small amount of radioactive dye, called a contrast agent, into the left ventricle through a catheter (a thin flexible tube). A special camera is then used to determine how much of the dye is ejected from the heart with each beat. The infusion of dye typically produces a characteristic "hot flash" sensation throughout the body that lasts 10-15 seconds.
Stress test: In some individuals, a less invasive procedure called a stress test is used to assess the possibility of coronary heart disease (CAD). If the results of this procedure suggest the presence of CAD, a subsequent referral for cardiac catheterization is likely.
Several types of stress tests may be used by doctors to access heart function. In some cases, the individual simply walks on a treadmill while connected to an ECG. Another type uses intravenous (IV, or in the veins) medication, usually a platelet inhibitor like dipyridamole (Persantine?), which reproduces the stress of exercise on the heart.
Nuclear stress test: Nuclear stress tests involve injecting a radioactive substance, most commonly technetium or Tc-99m sestamibi (Cardiolite?), into a vein. A special camera (gamma camera) is then used to obtain images of the heart during rest and immediately following exercise on a treadmill as the radioactivity flows through the heart. The radioactivity levels used are not harmful.
A nuclear test called a radionuclide ventriculography or multiple gated acquisition (MUGA) scanning allows doctors to see how much blood the heart pumps with each beat, also known as the ejection fraction. The MUGA scan gives an accurate and reproducible means of measuring and monitoring the actual amount of blood ejected from the heart. The tests use a small amount of radioactive material injected into the veins. A special camera detects the radioactive material as it flows through the heart.
Individuals with an allergy to iodine or shellfish have special considerations and may not be able to have this test because the dye contains iodine. The use of medications, including the antihistamine diphenhydramine (Benadryl?) and/or prednisone (Deltasone?), prior to the administration of the dyes (contrast media), may help to prevent or decrease the chance of an allergic reaction.
Classifying heart failure: Results of these tests help doctors determine the cause of CHF and develop a program to treat the heart. To determine the best course of treatment, doctors may classify heart failure using one of two scales. The New York Heart Association scale classifies heart failure in categories from one to four. In class I heart failure, the mildest form, individuals can perform everyday activities and not feel winded or fatigued. Individuals with class II have slight limitation of physical activity and ordinary physical activity may result in fatigue, palpitation (pounding or racing), shortness of breath, or chest pain. Those with class III have marked limitation of physical activity and less than ordinary activity causes fatigue, palpitation, shortness of breath, or chest pain. Class IV is the most severe, and individuals have shortness of breath even at rest.
The American College of Cardiology scale uses letters A-D. The system includes a category for individuals who are at risk of developing heart failure. Early stage heart failure includes stage A (individuals are at risk for developing heart failure without evidence of heart dysfunction) and stage B (there is evidence of heart dysfunction without symptoms). Advanced stage heart failure includes stage C (there is evidence of heart dysfunction with symptoms) and stage D (there are symptoms of heart failure despite maximal therapy). Doctors can use these classifications to identify the risk factors and begin early, more aggressive treatment to help prevent or delay heart failure.

Complications

The most common complication of most types of cardiomyopathy (dilated, hypertrophic, and restrictive) is heart failure, which may be fatal. Arrhythmias (abnormal heartbeats) and angina (chest pain) may also occur, especially in arrhythmogenic right ventricular cardiomyopathy (ARVC) in which heart failure is less common.

Treatment

General:
Treatment for cardiomyopathy aims at treating heart failure. This involves reducing symptoms, treating the underlying cause of the condition when possible, and using medications to prevent further deterioration of heart function. For arrhythmogenic right ventricular cardiomyopathy (ARVC), in which heart failure is less common, treatment is directed at preventing arrhythmia (irregular heartbeat).
Lifestyle changes:
Lifestyle changes may help reduce symptoms such as fatigue, shortness of breath, and edema (swelling). These modifications may include dietary changes (such as a restricted salt intake of less than 2,000 milligrams daily), abstaining from alcohol, smoking cessation, and exercising regularly (under the supervision of a doctor).
Medications:
A combination of medications is used to treat congestive heart failure (CHF). Depending on the symptoms, individuals with CHF may take one, two, or more of these drugs. Several types of medications have proved useful in the treatment of heart failure including: angiotensin-converting enzyme (ACE) inhibitors, angiotensin receptor blockers (ARBs), beta-blockers, digoxin, diuretics, and aldosterone antagonists.
Angiotensin-converting enzyme (ACE) inhibitors: Angiotensin-converting enzyme (ACE) inhibitors are medications that dilate or widen blood vessels to lower blood pressure, improve blood flow, and decrease the workload on the heart. Some examples of ACE inhibitors include enalapril (Vasotec?), lisinopril (Prinivil?, Zestril?), and captopril (Capoten?).
Side effects of ACE inhibitors include chronic, nonproductive cough (occurs in about 10% of patients), dizziness or weakness (caused by low blood pressure), increased potassium levels, skin rashes, and angioedema (sudden swelling of the lips, face, and cheeks; if this occurs, the patient must seek medical attention immediately).
Angiotensin II (A-II) receptor blockers (ARBs): Angiotensin receptor blockers, or ARBs, have many of the beneficial effects of ACE inhibitors, but they do not cause a persistent cough. They may be an alternative for individuals who cannot tolerate ACE inhibitors. Some examples of ARBs include losartan (Cozaar?) and valsartan (Diovan?).
Digoxin (Lanoxin?): Digoxin (Lanoxin?) increases the strength of the heart muscle contractions. Digoxin also tends to slow the heartbeat. Digoxin reduces heart failure symptoms and improves the individual's ability to live with CHF. Side effects may include blurred vision, cardiac problems (such as irregular heartbeat or heart block), diarrhea, headaches, loss of appetite, hypotension (low blood pressure), and nausea and vomiting. Rarely, digoxin may cause a disturbance of color (typically yellow and green) and halos around light. Most side effects are dose-dependent and occur when blood levels of the drug are more than the therapeutic range.
Beta-blockers: Beta-blockers are a class of drugs that slows the heart rate and reduces blood pressure. Some examples include carvedilol (Coreg?), metoprolol (Lopressor?), and propranolol (Inderal?). These medicines also reduce the risk of some abnormal heart rhythms. Beta-blockers may reduce signs and symptoms of heart failure and improve heart function. Beta-blockers are started at low doses that are gradually increased over a period of several months. During the first several weeks of treatment, some patients experience worsening symptoms, due to a decrease in oxygen circulation in the body. Other side effects include low blood pressure, difficulty breathing, sexual dysfunction, nausea, and weakness with exertion.
Diuretics: Diuretics or water pills decrease the amount of fluid in the body typically by increasing the rate of urination. Commonly prescribed diuretics for heart failure include hydrochlorothiazide (Diuril?) and furosemide (Lasix?). Diuretics also decrease fluid in the lungs, helping individuals breathe more easily. Common side effects include frequent urination and low potassium blood levels (hypokalemia) or high potassium levels (hyperkalemia), depending on the diuretic. Because of this, blood tests are performed periodically and a potassium supplement is prescribed if blood levels are low. Individuals may be asked to eat more fruits high in potassium, such as bananas and oranges, while on diuretic therapy. Other side effects include low sodium levels (hyponatremia), increased blood sugar (hyperglycemia), increased cholesterol (hyperlipidemia), rash, joint disorders (e.g., gout), impotence (men), menstrual irregularities (women), and breast enlargement in men.
Aldosterone antagonists: Aldosterone antagonists are primarily potassium-sparing diuretics, but they have additional properties that help the heart work better, may reverse scarring of the heart, and may help individuals with severe heart failure live longer. Aldosterone antagonists include spironolactone (Aldactone?) and eplerenone (Inspra?). Unlike other diuretics, spironolactone can raise the level of potassium in the blood to dangerous levels. Healthcare professionals recommend eliminating high-potassium foods, such as bananas, lentils, nuts, peaches, potatoes, salmon, tomatoes, and watermelon while taking aldosterone antagonists.
Others: A medication called BiDil? is a single pill that combines hydralazine and isosorbide dinitrate, both of which dilate and relax the blood vessels. BiDil? increases survival when added to standard therapy in African American individuals with advanced heart failure. This is the first drug studied and approved for a specific racial group following the results of a human trial that found the medication reduced death, hospitalizations, and symptoms of heart failure among black patients who tried other agents. Further studies will be necessary to determine if this combination medicine will be helpful for others with heart failure. Side effects may include blurred vision, dry mouth, irregular heartbeat, blood in the urine or stools, numbness or tingling in the arms or legs, and fainting.
Doctors often prescribe other medications such as HMG-CoA reductase inhibitors (statin) drugs for cholesterol reduction. Some examples are atorvastatin (Lipitor?) and lovastatin (Mevacor?). They may cause liver problems or muscle pain. Anti-arrhythmic drugs may also be prescribed to control irregular heartbeats, including diltiazem (Cardizem?, Cardizem CR?) and verapamil (Calan?, Calan SR?).
Individuals may be hospitalized for a few days if complications arise as a result of CHF symptoms. While in the hospital, individuals may receive additional medications such as intravenous (IV, or into the veins) dobutamine (Dobutrex?), milrinone, (Primacor?), and nitroglycerin. These drugs work quickly to help the heart pump better and relieve symptoms. Individuals may also receive supplemental oxygen through a mask or small tubes placed in the nose. If severe heart failure is present, the individual may need to use supplemental oxygen long term.
Individuals hospitalized with severe CHF may be given an intravenous drug called nesiritide (Natrecor?). Nesiritide is a synthetic version of a naturally occurring hormone in the body called brain natriuretic peptide (BNP). BNP is secreted in high levels by the heart in response to a failing heart. However, it is not clear if nesiritide is better than other intravenous medications for severe heart failure. Studies are ongoing to evaluate the safety and effectiveness of nesiritide in heart failure.
Other treatments:
Aquapheresis: In some cases, heart failure persists or worsens in spite of treatment. An ultrafiltration process called aquapheresis, which uses a mechanical system called the Aquadex FlexFlowT, may be used to remove excess fluids and salt in CHF individuals who do not respond to lifestyle modifications and medication. In this treatment, blood is withdrawn using catheters (small tubes) inserted into veins in the arm, leg, or neck. The blood is then passed through a filter that removes excess fluid and is returned to the body. Studies have reported that ultrafiltration can remove more fluid at a faster rate than medication. The length of each treatment depends on the rate at which fluid can be removed from the body and the amount that must be removed. Low blood pressure (hypotension) may occur.
Angioplasty: CHF caused by reduced blood flow in the heart as a result of blockages (plaques) in one or more coronary arteries may be treated using coronary angioplasty. In this procedure, a hollow tube (catheter) is inserted through an artery (usually the femoral artery in the groin), into the coronary artery, and to the blockage. A small balloon is then inserted through the catheter and is inflated to open the blocked artery. There is a slight risk for damage to the artery during angioplasty, but heart failure symptoms usually improve following the procedure. Stenting is used along with balloon angioplasty. Stenting involves placing a mesh-like metal device into an artery at a site narrowed by plaque. The stent is mounted on a balloon-tipped catheter, threaded through an artery, and positioned at the blockage. The balloon is then inflated, opening the stent. Then the catheter and deflated balloon are removed, leaving the stent in place. The opened stent keeps the vessel open and stops the artery from collapsing. Re-closure may occur with both balloon angioplasty and stenting. Doctors may prescribe blood thinning medications to help keep the arteries open, including aspirin, warfarin (Coumadin?), and clopidogrel (Plavix?).
Coronary artery bypass graft surgery (CABG): A coronary artery bypass surgery (CABG) may be recommended if the individual has severe coronary artery disease (CAD) in addition to CHF. This may improve the blood supply to the heart. CABG surgery uses blood vessel grafts, which usually come from the patient's own arteries and veins located in the chest, leg, or arm. The graft goes around the clogged artery to create new pathways for oxygen-rich blood to flow to the heart. Some problems associated with CABG include a heart attack (occurs in five percent of patients), stroke (occurs in five percent, with the risk greatest in those more than 70 years old), blood clots, death (occurs in 1-2% of individuals), and wound infection (occurs in 1-4%). Infection is most often associated with obesity, diabetes, or having had a previous CABG. In about 30% of patients, post-pericardiotomy syndrome may occur anywhere from a few days to six months after surgery. The symptoms of this syndrome are fever and chest pain. Symptoms may be treated with medications, including antibiotics (for infection), nitroglycerin, and anti-inflammatory drugs. The incision in the chest or the graft site (if the graft was from the leg or arm) may be itchy, sore, numb, or bruised. Some individuals report memory loss, loss of mental clarity, or "fuzzy thinking" following a CABG.
Implantable cardiac defibrillator (ICD): An implantable cardiac defibrillator (ICD) may be used to treat severe heart failure. An ICD is a small electronic device that is surgically implanted under the skin in the chest to monitor heart rhythm. When an abnormal rhythm is detected, the defibrillator delivers an electrical shock to the heart to restore normal heart rhythm.
Intra-aortic balloon pump (IABP): An intra-aortic balloon pump (IABP) is a device that is inserted through an artery in the groin (femoral artery) and then placed within the main artery (aorta). An IABP is an inflatable balloon that expands and deflates in coordination with each heartbeat. It can be left in place for days to weeks, and decreases the strain on the heart and increases blood flow throughout the body.
Valve replacement surgery: Individuals with heart failure caused by an abnormal heart valve may require valve repair or valve replacement surgery. These are open-heart procedures in which an abnormal valve is repaired or replaced with a porcine valve (from pig tissue), a mechanical valve (made of synthetic material), or a homograft valve (from a human donor). Complications include bleeding, blood clots, infection, kidney failure, stroke, heart attack, valve rejection, and death. A homograft valve is preferred, as these valves are not associated with a significant risk for blood clot formation and, thus, do not require blood thinner therapy. Most individuals remain in the hospital for a week after surgery, and recovery takes approximately 3-4 weeks, after which most patients may resume leisure activities and many return to work. Approximately 60% of individuals who have valve replacement have a 10-year post-surgery survival rate.
Left ventricular assist device: A left ventricular assist device (LVAD) is a mechanical pump that is surgically implanted in the upper abdomen to bypass the left ventricle and pump blood throughout the body. This device may be used in patients with end-stage heart failure who are awaiting heart transplantation. Long-term use of the device in patients with severe heart failure is being explored and has not yet been defined.
Pacemaker: If individuals with CHF experience abnormal heart rhythms that will not respond to medication therapy, the irregular heart rhythms may be corrected with a pacemaker. A pacemaker is a small, battery-powered device that is usually implanted near the collarbone. Pacemakers can be surgically placed into the chest (a permanent pacemaker) through a small incision, or they can be worn outside the body (a temporary pacemaker) and attached to the heart through a wire that is threaded through a neck vein. Temporary pacemakers are used only while an individual is in the hospital.
The surgery needed to implant a permanent pacemaker is considered a minor surgical procedure. The procedure may take 1-2 hours to complete. The area where the pacemaker will be inserted will be numbed with an injection of an anesthetic such as lidocaine (Xylocaine?). The individual should not feel any pain during the procedure, and should inform the doctor or staff if he or she is having pain so that more anesthetic medication may be given. One or more electrode-tipped wires run from the pacemaker through the blood vessels to the inner heart. If the heart rate is too slow or if it stops, the pacemaker sends out electrical impulses that stimulate the heart to beat at a steady, proper rate. The more advanced pacemakers can monitor and pace either the atria or ventricles (or both) in proper sequence to maximize the amount of blood being pumped from the heart. The pacemaker's batteries may need to be changed every 5-10 years. It is recommended by the American Heart Association (AHA) to limit exposure to devices that may interfere with pulse generators such as cellular phones, CB radios, electric blankets, and microwaves.
It is normal for the surgical wound to be somewhat painful and swollen for a few days after the procedure. This can usually be controlled with medications, such as tramadol (Ultram?) or ibuprofen (Motrin?). The wound may also appear mildly red for a few days; however, if the area of redness enlarges, a doctor should be notified due to the potential for a serious infection. If there are no other problems, most individuals who have a permanent pacemaker surgically implanted can go home the next day. They may usually return to normal activities within six weeks. For several weeks after having a pacemaker implanted, the individual may be asked not to lift more than five pounds or raise the affected arm over their shoulder.
Heart transplant: In some cases, despite the use of optimal therapies, the individual's condition continues to deteriorate, due to progressive CHF. In selected individuals, heart transplantation is a viable treatment option. Candidates for a heart transplant are generally younger than age 70, do not smoke, and do not have severe or irreversible diseases affecting the other organs. Additionally, a transplant is done only when it is clear that the individual's prognosis (expected outcome) on the continued medical treatment is poor. Transplant patients require close medical follow-up while taking needed drugs that suppress the immune system because of the risk of rejection of the transplanted heart. They are even monitored for possible development of CAD in the transplanted heart.
Although there are thousands of patients on waiting lists for a heart transplant at any given time, the number of operations performed each year is limited by the number of available donor organs. For these reasons, heart transplantation is a realistic option in only a small subset of the large numbers of patients with CHF.

Integrative therapies

Strong scientific evidence:
Hawthorn: Hawthorn (Crataegus spp.), a flowering shrub of the rose family has an extensive history of use in cardiovascular disease dating back to the 1st Century. Increased blood flow to the heart and heart performance has been observed in animals when given hawthorn supplements. Extracts of the leaves and flowers of hawthorn have been reported as effective in the treatment of mild-to-moderate congestive heart failure (CHF), improving exercise capacity and reducing symptoms of cardiac insufficiency. However, whether hawthorn is as effective as drugs considered standard-of-care for heart failure (such as angiotensin converting enzyme (ACE) inhibitors, diuretics, or beta-adrenergic receptor blockers) is unclear, as is the effect of the combined use of hawthorn with these drugs. Nonetheless, hawthorn is a potentially beneficial treatment for patients who cannot or will not take prescription drugs and may offer additive benefits to established therapies. Further study is warranted.
Avoid if allergic to hawthorn or to members of the Crataegus species. Avoid with a history of low blood pressure, irregular heartbeat, asthma, low blood pressure when standing, or insomnia. Use cautiously in elderly patients. Avoid if pregnant or breastfeeding.
Good scientific evidence:
Arginine: Studies of arginine in patients with chronic heart failure (CHF) have shown mixed results. Some studies report improved exercise tolerance. Additional studies are needed to confirm these findings.
Avoid if allergic to arginine, or with a history of stroke, or liver or kidney disease. Avoid if pregnant or breastfeeding. Use caution if taking blood-thinning drugs (like warfarin or Coumadin?) and blood pressure drugs or herbs or supplements with similar effects. Blood potassium levels should be monitored as arginine may increase potassium levels. L-arginine may worsen symptoms of sickle cell disease. Caution is advised in patients taking prescription drugs to control blood sugar levels.
Berberine: Berberine is a bitter-tasting, yellow, plant alkaloid with a long history of medicinal use in Chinese and Ayurvedic medicine. Berberine is present in the roots, rhizomes, and stem bark of various plants including Hydrastis canadensis (goldenseal), Coptis chinensis (coptis or goldenthread), Berberis aquifolium (Oregon grape), Berberis vulgaris (barberry), and Berberis aristata (tree turmeric). Preliminary clinical research suggests that berberine, in addition to a standard prescription drug regimen for chronic CHF, may improve quality of life, heart function, and risk of mortality. Further research is necessary.
Berberine has been reported to cause nausea, vomiting, hypertension (high blood pressure), respiratory failure, and paresthesias (abnormal sensations such as numbness or tingling). Use cautiously in patients with diabetes. Avoid if allergic or hypersensitive to berberine, to plants that contain berberine [Hydrastis canadensis (goldenseal), Coptis chinensis (coptis or goldenthread), Berberis aquifolium (Oregon grape), Berberis vulgaris (barberry), and Berberis aristata (tree turmeric)], or to members of the Berberidaceae family. Avoid in newborns due to potential for increase in free bilirubin, jaundice, and development of kernicterus (a type of brain damage). Use cautiously with cardiovascular disease, gastrointestinal disorders, hematologic disorders, leucopenia, kidney disease, liver disease, respiratory disorders, cancer, hypertyraminemia, diabetes, or hypotension (low blood pressure). Use cautiously in children, due to lack of safety information. Use cautiously in individuals with high exposure to sunlight or artificial light. Use cautiously for longer than eight weeks, due to theoretical changes in bacterial gut flora. Use cautiously if taking anticoagulants, antihypertensives, sedatives, anti-inflammatories, medications metabolized by CYP P450 3A4 including cyclosporin, or any prescription medications. Avoid if pregnant or breastfeeding.
Coleus: Coleus species have been used in Asian traditional medicine for several indications. Since the 1970s, research was predominantly concentrated on forskolin, a root extract of Coleus forskohlii. A small number of studies suggest that forskolin may improve cardiovascular function in patients with cardiomyopathy. However, these trials are small and of poor quality. Larger studies are needed.
Coleus is generally regarded as safe, although long-term safety data are lacking. Avoid with a known allergy or hypersensitivity to Coleus forskohlii and related species. Rash may occur in sensitive individuals. Inhalation of forskolin may cause sore throat, upper respiratory tract irritation, mild-to-moderate cough, tremor, or restlessness. Coleus eye drops may produce a milky covering over the eyes. Use cautiously in patients with heart disease, asthma, thyroid disorders, diabetes, a history of bleeding, hemostatic disorders or drug-related hemostatic problems, low blood pressure, or in patients at risk for low blood pressure. Discontinue use in patients at least two weeks prior to surgical or dental procedures, due to risk of bleeding. Avoid in patients with active bleeding. Avoid during pregnancy.
Creatine: Creatine is naturally synthesized in the human body from amino acids primarily in the kidney and liver, and transported in the blood for use by muscles. Cardiac creatine levels have been reported as depressed in patients with chronic CHF. Several studies report that creatine supplementation is associated with improved heart muscle strength, body weight, and endurance in patients with heart failure. However, it is not clear what dose may be safe or effective. Supplementation is also reported to increase creatine in the skeletal muscle in these patients, helping to increase strength and endurance. Well-designed studies comparing creatine with drugs used to treat heart failure are needed.
Avoid if allergic to creatine or with diuretics (such as hydrochlorothiazide, furosemide (Lasix?)). Use caution in asthma, diabetes, gout, kidney, liver, or muscle problems, stroke or a history of these conditions. Avoid dehydration. Avoid if pregnant or breastfeeding.
Selenium: Keshan disease is a cardiomyopathy (heart disease) restricted to areas of China in people having an extremely low selenium status. Prophylactic administration of sodium selenite has been shown to significantly decrease the incidence of this disorder. Organic forms of selenium (such as selenized yeast or Se-yeast) may have better bioavailability than selenite and thus may be better preventative treatments for Keshan disease. Selenium is used to treat and prevent selenium deficiency (for example in those with HIV or receiving enteral feedings).
Selenium is a trace element and hypersensitivity is unlikely. Avoid individuals with a known allergy/hypersensitivity to products containing selenium.
The level of selenium exposure that will cause chronic toxicity is not known. Selenium toxicity may cause gastrointestinal symptoms (nausea, vomiting, abdominal pain, diarrhea, garlic-like breath odor, and metallic taste), neuromuscular-psychiatric disturbances (weakness/fatigue, lightheadedness, irritability, hyperreflexia, muscle tenderness, tremor, and peripheral neuropathy), dermatologic changes (skin rash/dermatitis/flushing, fingernail loss/thickening/blotching/streaking/paronychia, and hair changes/loss), liver dysfunction, kidney dysfunction, thrombocytopenia (low blood platelets), immune alterations (natural killer cell impairment), thyroid dysfunction (decreased T3), reduced sperm motility, or growth retardation.
Unclear or conflicting scientific evidence:
Aconite: The toxic effects associated with aconite limit its ability to be used to treat heart failure, including reno-cardiovascular disease and left ventricular function. Further study is needed.
Aconite is highly toxic and is not safe for human consumption. Avoid with heart disease, heart dysfunction, irregular heartbeat, hemodynamic instability (abnormal blood flow), gastrointestinal disorders, ulcers, reflux esophagitis, ulcerative colitis, spastic colitis, and diverticulosis. Use caution with diabetes and suicidal tendencies. Avoid if younger than 18 years. Avoid if pregnant or breastfeeding.
Astragalus: Astragalus (Astragalus membranaceus) is used in combination with other herbs in Chinese medicine to treat various heart diseases. There is some evidence that astragalus may offer symptomatic improvement for chronic heart failure. Recommendations cannot be made until well-designed clinical trials have been conducted.
Avoid if allergic to astragalus, peas, or any related plants or with a history of Quillaja bark-induced asthma. Avoid with aspirin or aspirin products or herbs or supplements with similar effects. Avoid with inflammation (swelling) or fever, stroke, transplant or autoimmune diseases (such as HIV/AIDS or human immunodeficiency virus/acquired immunodeficiency syndrome). Stop use two weeks before surgery/dental/diagnostic procedures with a risk of bleeding and avoid use immediately after these procedures. Use cautiously with bleeding disorders, diabetes, high blood pressure, lipid disorders, or kidney disorders. Use cautiously with blood-thinners, blood sugar drugs, or diuretics, or herbs and supplements with similar effects. Avoid if pregnant or breastfeeding.
Ayurveda: Ayurveda, which originated in ancient India more than 5,000 years ago, is probably the world's oldest system of natural medicine. Preliminary evidence suggests that sodium nimbidinate, made from the traditional Ayurvedic herb Nimba/Neem/Arishta (Azadirachta indica), may be an effective diuretic in patients with congestive heart failure (CHF). More studies are needed to confirm this effect.
Ayurvedic herbs should be used cautiously because they are potent and some constituents may be potentially toxic if taken in large amounts or for a long time. Some herbs imported from India have been reported to contain high levels of toxic metals. Ayurvedic herbs may interact with other herbs, foods, and drugs. A qualified healthcare professional should be consulted before taking.
Camphor: Preliminary evidence indicates that a German combination product of camphor and extract of hawthorn berries (Korodin? Herz-Kreislauf-Tropfen) may reduce overall symptoms in patients with functional cardiovascular disease. While these early findings are promising, further research is required before any recommendation can be made.
Camphor and camphor-containing products are generally applied as topical formulations. Ingestion of such preparations is not recommended, as they are potentially poisonous and may induce a number of adverse and potentially fatal side effects. Caution is advised for use of any internal preparations of camphor due to their potential toxicity.
Coenzyme Q10 (CoQ10): CoQ10 is produced by the human body and is necessary for the basic functioning of cells. The evidence for CoQ10 in the treatment of heart failure is controversial and remains unclear. Different levels of disease severity have been studied (New York Heart Association classes I through IV). Better research is needed in this area, studying effects on quality of life, hospitalization, and death rates. There is also conflicting evidence from research on the use of CoQ10 in patients with dilated or hypertrophic cardiomyopathy.
CoQ10 is generally safe in recommended dosages, but further studies are needed.
Allergy associated with CoQ10 supplements has not been reported, although rash and itching have been reported rarely. Stop use two weeks before surgery/dental/diagnostic procedures with bleeding risk and do not use immediately after these procedures. Use caution with a history of blood clots, diabetes, high blood pressure, heart attack, or stroke, or with anticoagulants (blood thinners), antiplatelet drugs (such as aspirin, warfarin, clopidogrel (e.g., Plavix?), or blood pressure, blood sugar, cholesterol or thyroid drugs. Avoid if pregnant or breastfeeding.
Ginseng: A clinical study on the effect of Panax ginseng on CHF did not show a clear benefit of combining digoxin with ginseng. The relatively small study size and the use of a drug instead of a standardized extract limit the value of the evidence. Additional research is needed.
Ginseng may also lower blood pressure. Caution is used when taking ginseng supplements, as adverse effects and drug interactions are possible. Ginseng supplements should not be used if pregnant or breastfeeding unless otherwise directed by a doctor.
Goldenseal: Limited available study suggests that berberine (the active compound of goldenseal) in addition to a standard prescription drug regimen for CHF may improve quality of life and decrease ventricular premature complexes (VPCs) and mortality. Further research is needed to confirm these results.
Use cautiously in patients with gastrointestinal disorders, cardiovascular disease, bleeding disorders or in those taking anticoagulants, diabetes or in those taking antidiabetic agents. Use cautiously in infants with increased bilirubin levels or individuals with glucose-6-phosphate deficiency. Use cautiously in pregnancy.
Hawthorn: Herbal combinations containing hawthorn have been found effective in the treatment of functional cardiovascular disorders. However, due to a lack of information on the use of hawthorn alone, there is not enough evidence to recommend for or against this use of hawthorn.
Avoid if allergic to hawthorn or to members of the Crataegus species. Avoid with a history of low blood pressure, irregular heartbeat, asthma, low blood pressure when standing, or insomnia. Use cautiously in elderly patients. Avoid if pregnant or breastfeeding.
L-carnitine: L-carnitine, carnitine, or acetyl-L-carnitine, is an amino acid found in the body. Although preliminary results are promising, there is insufficient available clinical evidence for the use of L-carnitine in CHF.
Avoid with a known allergy or hypersensitivity to carnitine. Use cautiously with peripheral vascular disease, hypertension (high blood pressure), alcohol-induced liver cirrhosis, and diabetes. Use cautiously in low birthweight infants and individuals on hemodialysis. Use cautiously if taking anticoagulants (blood thinners), beta-blockers, or calcium channel blockers. Avoid if pregnant or breastfeeding.
Meditation: Meditation may improve quality of life in elderly patients, and may potentially reduce the risk for CHF. However, there is not enough evidence to make a conclusion.
Use cautiously with underlying mental illnesses. People with psychiatric disorders should consult with their primary mental healthcare professional(s) before starting a program of meditation, and should explore how meditation may or may not fit in with their current treatment plan. Avoid with risk of seizures. The practice of meditation should not delay the time to diagnosis or treatment with more proven techniques or therapies, and should not be used as the sole approach to illnesses.
Oleander: The term oleander refers to two plants: Nerium oleander (common oleander) and Thevetia peruviana (yellow oleander). Both plants contain heart-active cardiac glycoside chemicals (similar to the prescription drug digoxin) and have been associated with serious side effects in humans, including death. The plants have been used to treat CHF in China and Russia for decades, but scientific evidence supporting this use is limited to small, poorly designed studies. Human research began in the 1930s, but was largely abandoned due to serious gastrointestinal and heart toxicity.
All parts of the oleander plant, including flowers, leaves, and nectar are considered toxic and may cause death. Avoid if allergic to oleander or other cardiac glycosides such as digoxin. Avoid with a history of irregular heartbeat (arrhythmia), seizures, liver or kidney disease, depression, or asthma. Avoid if pregnant or breastfeeding.
Passion flower: An extract containing passionflower and hawthorn has been studied for potential enhancement of exercise capacity in CHF patients. Individuals using this combination of herbs have experienced improvements in symptoms; however, any positive effects may have resulted from hawthorn, which is more commonly used for congestive heart failure. High quality human research of passion flower alone and compared to prescription drugs used for this condition is needed.
Avoid if allergic to passionflower or any of its constituents. Avoid consuming raw Passiflora fruit (Passiflora adenopoda), due to possible cyanide constituents. Passionflower extracts may cause drowsiness in sensitive individuals. Avoid driving or operating heavy machinery while taking passionflower. Use cautiously with low blood pressure. Avoid if pregnant or breastfeeding.
Physical therapy: Both supervised and home-based exercise training may enhance exercise capacity in patients with CHF. However, consensus has not been obtained regarding a standard rehabilitation program for these patients, and the literature often suggests individually-tailored programs. Due to the lack of standardization, duration of treatment, and various outcomes' measures, more study is needed before a conclusion can be made.
Not all physical therapy programs are suited for everyone, and patients should discuss their medical history with a qualified healthcare professional before beginning any treatments. Physical therapy may aggravate pre-existing conditions. Persistent pain and fractures of unknown origin have been reported. Physical therapy may increase the duration of pain or cause limitation of motion. Pain and anxiety may occur during the rehabilitation of patients with burns. Both morning stiffness and bone erosion have been reported in the literature although causality is unclear. Erectile dysfunction has also been reported. Physical therapy has been used in pregnancy and although reports of major adverse effects are lacking in the available literature, caution is advised nonetheless. All therapies during pregnancy and breastfeeding should be discussed with a licensed obstetrician/gynecologist before initiation.
Relaxation therapy: Early studies suggest that progressive muscle relaxation training may benefit patients with heart failure when used in combination with standard care.
Avoid with psychiatric disorders such as schizophrenia/psychosis. Jacobson relaxation (flexing specific muscles, holding that position, and then relaxing the muscles) should be used cautiously with illnesses such as heart disease, high blood pressure, or musculoskeletal injury. Relaxation therapy is not recommended as the sole treatment approach for potentially serious medical conditions, and should not delay the time to diagnosis or treatment with more proven techniques.
Selenium: Low selenium levels have been associated with the development of cardiomyopathy, and selenium supplementation is likely of benefit in such cases (for example in Keshan disease and Chagas' disease). However, most cases of cardiomyopathy are not due to low selenium levels and therefore selenium may not be helpful. It has been suggested that low selenium levels may be a risk factor for coronary heart disease, although this remains unclear.
Avoid if allergic or sensitive to products containing selenium. Avoid with a history of nonmelanoma skin cancer. Selenium is generally regarded as safe for pregnant or breastfeeding women. However, animal research reports that large doses of selenium may lead to birth defects.
Taurine: Taurine is a nonessential amino acid-like compound, found in high abundance in the tissues of many animals, especially sea animals, and in much lower concentrations in plants, fungi, and some bacteria. Preliminary study suggests that taurine may be beneficial as an adjunct to traditional medications for symptoms of CHF. Further study is warranted to confirm these findings.
Taurine appears to be safe in recommended dosages. As an amino acid, it is unlikely that there are allergies related to this constituent. However, allergies may occur from multi-ingredient products that contain taurine. Use cautiously in patients with high cholesterol, low blood pressure, coagulation disorders, potential for mania, or epilepsy. Avoid alcohol or exercise after consumption of energy drinks containing taurine, caffeine, glucuronolactone, B vitamins, and other ingredients. Use cautiously if pregnant or breastfeeding; taurine is a natural component of breast milk
Thiamin: Thiamin (also spelled "thiamine") is a water-soluble B-complex vitamin, previously known as vitamin B1 or aneurine. Thiamin was isolated and characterized in the 1920s, and thus was one of the first organic compounds to be recognized as a vitamin. Chronic severe thiamin deficiency may cause heart failure (wet beriberi), a condition that merits thiamin supplementation. Currently, it is not clear if thiamin supplementation is beneficial in patients with heart failure due to other causes. However, it is reasonable for patients with heart failure to take a daily multivitamin including thiamin, because some of these individuals may be thiamin deficient. Diuretics may lower thiamin levels. Since diuretics are commonly administered to patients with heart failure, patients taking diuretics are at an increased risk of thiamin deficiency. This area remains controversial, and further evidence is necessary before a conclusion can be reached. Excessive alcohol consumption may cause thiamin deficiency.
Avoid if allergic or hypersensitive to thiamin. Rare hypersensitivity/allergic reactions have occurred with thiamin supplementation. Skin irritation, burning, or itching may rarely occur at injection sites. Large doses may cause drowsiness or muscle relaxation. Use cautiously if pregnant or breastfeeding with doses higher than the U.S. Recommended Daily Allowance (RDA).
Thymus extract: The thymus is a lobular gland located under the breastbone near the thyroid gland. It reaches its maximum size during early childhood and plays a large role in immune function. Preliminary evidence suggests that thymus extract may increase left ventricular function, exercise tolerance, and survival in patients with cardiomyopathy. Additional research is needed to confirm these results.
It is important to use high quality thymus gland supplements due to contamination concerns. Avoid if allergic or hypersensitive to thymus extracts. Use bovine thymus extract supplements cautiously due to potential for exposure to the virus that causes mad cow disease. Avoid use with an organ transplant or other forms of allografts or xenografts. Avoid if receiving immunosuppressive therapy, with thymic tumors, myasthenia gravis (neuromuscular disorder), untreated hypothyroidism, or if taking hormonal therapy. Avoid if pregnant or breastfeeding; thymic extract increases human sperm motility and progression.
Traditional Chinese medicine (TCM): Many studies of traditional Chinese medicine (TCM) herbs have focused on treatment of CHF. Further research of better design is needed before recommendations can be made.
Chinese herbs can be potent and may interact with other herbs, foods or drugs. Consult a qualified healthcare professional before taking. There have been reports of manufactured or processed Chinese herbal products being tainted with toxins or heavy metals or not containing the listed ingredients. Herbal products should be purchased from reliable sources. Avoid ma huang, which is the active ingredient in ephedra. Avoid ginseng if pregnant or breastfeeding.
Fair negative scientific evidence:
Guided imagery: Therapeutic guided imagery may be used to help individuals relax and focus on images associated with personal issues they are confronting. Preliminary human research does not report benefits of guided imagery in congestive heart failure (CHF).
Guided imagery is usually intended to supplement medical care, not to replace it, and guided imagery should not be relied on as the sole therapy for a medical problem. Contact a qualified healthcare provider if mental or physical health is unstable or fragile. Never use guided imagery techniques while driving or doing any other activity that requires strict attention. Use cautiously with physical symptoms that may be brought about by stress, anxiety, or emotional upset because imagery may trigger these symptoms. If feeling unusually anxious while practicing guided imagery, or with a history of trauma or abuse, speak with a qualified healthcare provider before practicing guided imagery.

Prevention

General: Coronary artery disease (CAD) and hypertension (high blood tension) may cause or worsen existing cardiomyopathy. Therefore, preventative measures for cardiomyopathy aim at reducing the risk of CAD.
Smoking cessation: Smoking damages blood vessels, reduces the amount of oxygen in the blood, and makes the heart beat faster. If an individual smokes, a doctor may help recommend a program or treatment option to help them quit. Individuals are not considered for a heart transplant if smoking is continued.
Weight control: It is recommended that individuals weigh themselves each morning after urination, but before breakfast. Notify a doctor if there is a weight gain of three or more pounds in a day. Weight gain may indicate fluid build-up.
Being overweight contributes to other risk factors for stroke, such as high blood pressure, cardiovascular disease, and diabetes. Weight loss of as little as ten pounds may lower blood pressure and improve cholesterol levels.
Exercise may lower blood pressure, increase the level of high density lipoprotein (HDL cholesterol or good cholesterol), and improve the overall health of blood vessels and heart. It also helps control weight, control diabetes, and reduce stress. Cardiac rehabilitation programs exist for individuals recovering from heart surgery. Cardiac rehabilitation is a medically supervised program to help heart patients recover quickly and improve their overall physical, mental, and social functioning. The goal is to stabilize, slow, or even reverse the progression of cardiovascular disease, thereby reducing the risk of heart disease, another cardiac event, or death. Cardiac rehabilitation programs include: counseling so the individual can understand and manage the disease process; an exercise program; counseling on nutrition; helping the patient modify risk factors such as high blood pressure, smoking, high blood cholesterol, physical inactivity, obesity, and diabetes; providing vocational guidance to enable the patient to return to work; information on physical limitations; lending emotional support; and counseling on appropriate use of prescribed medications. A doctor may help initiate an exercise program and cardiac rehabilitation tailored to the individual with congestive heart failure (CHF).
Salt restriction: Too much sodium (from salt) contributes to water retention, which makes the heart work harder. Excess sodium may causes shortness of breath and swollen legs, ankles, and feet. For individuals with heart failure the recommended sodium intake is no more than 2,000 milligrams daily. Some substitutes or "lite" salts contain a mixture of salt and other compounds. To get that familiar salty taste, individuals may use too much of the substitute and actually not reduce sodium intake. In addition, many salt substitutes contain potassium chloride. Too much potassium may be harmful. A dietitian may help outline a healthy, low-salt diet.
Stress management: Stress may cause an increase in blood pressure along with increasing the blood's tendency to clot. Managing stress may be vital to keeping a heart healthy.
Diet modification: Eating healthy foods is important. A heart-healthy diet includes five or more daily servings of fruits and vegetables, foods rich in soluble fiber (such as oatmeal and beans), foods rich in calcium (dairy products, spinach), soy products (such as tempeh, miso, tofu, and soy milk), and foods rich in omega-3 fatty acids, including cold-water fish, such as salmon, mackerel, and tuna. Pregnant women and women who plan to become pregnant in the next several years should limit their weekly intake of cold-water fish because of the potential for mercury contamination. Limiting red meats and high fat foods (such as doughnuts, cookies, and chips) is recommended by healthcare professionals.
Alcohol: Excessive use of alcohol may weaken the heart muscle or increase the risk of abnormal heart rhythms, increasing the risk of cardiomyopathy and resultant heart failure. Alcohol may also interact with some medications used to treat heart conditions. However, moderate alcohol consumption (such as one glass of red wine daily) may be beneficial for heart health.
Swelling: Leg, ankle, and foot edema can be improved by elevating the legs above heart level for 30 minutes 3-4 times daily. Leg elevation alone may be sufficient therapy for patients with mild venous insufficiency, but is usually not adequate for more severe cases. In addition, it may not be practical for those who work to elevate their legs several times daily.
Leg edema (swelling) can also be prevented and treated with the use of compression stockings. Many types are available, including knee-high, thigh-high, and pantyhose. Knee-high stockings are sufficient for most individuals; thigh-high stockings are less desirable because they tend to provide too much pressure behind the knees, reducing blood flow in the veins, and causing discomfort. The stockings should be put on as early as possible in the morning when edema is minimal. Healthcare professionals can help with choosing the right compression stocking for each individual.
Contraception: Because women who have previously had peripartum cardiomyopathy are at increased risk of developing cardiomyopathy with future pregnancies, they may consider contraception to prevent future pregnancies.

Author information

This information has been edited and peer-reviewed by contributors to the Natural Standard Research Collaboration (www.naturalstandard.com).

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Causes

General: Cardiomyopathy refers to several diverse diseases that affect the myocardium (heart muscle). Different forms of cardiomyopathy have distinct causes. Primary cardiomyopathies may be inherited, acquired, or both. Secondary cardiomyopathies are caused by other conditions, including diabetes, thyroid disorders, chronic alcohol consumption, infection, or drugs/toxins (e.g., heavy metals, anthracyclines, cocaine).
Arrhythmogenic right ventricular cardiomyopathy (ARVC): Arrhythmogenic right ventricular cardiomyopathy (ARVC, formerly known as arrhythmogenic right ventricular dysplasia or ARVD) is a genetic disease caused by mutations in genes that affect heart muscle cells. The most common genetic causes of ARVC are mutations in the plakophilin 2 (PKP2) gene, which produces a protein that helps myocardial cells attach to each other. Mutations in PKP2 that cause ARVD result in defective forms of the plakophilin 2 protein. Although mutations in PKP2that cause ARVC are usually autosomal dominant, which means that they would affect both sexes equally, ARVC occurs in men three times more often than in women. It is unclear why more men are affected; however, it appears that physical activity may increase the risk of arrhythmia (abnormal heart beat) in ARVD.
Dilated cardiomyopathy: There are multiple factors (primary or secondary) that may cause different forms of dilated cardiomyopathy. The most common form, ischemic cardiomyopathy, is most often caused by coronary artery disease (CAD) and/or high blood pressure; however, viral infections, other heart diseases, or genetics may also lead to ischemic cardiomyopathy. Peripartum cardiomyopathy is diagnosed in pre- or postnatal mothers when other known causes of dilated cardiomyopathy have been excluded. It is unclear what exactly causes peripartum cardiomyopathy; however, risk factors include obesity, pregnancy-induced hypertension (preeclampsia), multiple pregnancy (such as twins or triplets), or being more than 30 years of age. Stress (physical or emotional) or excessive alcohol consumption may also cause dilated cardiomyopathy
Hypertrophic cardiomyopathy (HCM): Hypertrophic cardiomyopathy (HCM) is a genetic disease caused by mutations in genes that produce sarcomere proteins. Sarcomeres are units of myofibrils, which are threadlike strands that make up the muscle that contracts the heart. Because HCM is usually inherited, having a parent with the condition increases the risk of inheriting the gene that causes HCM. While HCM is often asymptomatic, physical activity greatly increases the risk of complications and sudden death, due to HCM.
Restrictive cardiomyopathy: Restrictive cardiomyopathy is usually secondary to another acquired or inherited heart disease (such as amyloidosis, endomyocardial fibrosis, or sarcoidosis). It may also occur after a heart transplant, and having any disease or injury that affects the heart muscle may increase the risk of restrictive cardiomyopathy. Heritable forms of restrictive cardiomyopathy are most often caused by mutations in genes that produce troponin, a muscle protein that aids in muscle contraction.

Risk factors

Arrhythmogenic right ventricular cardiomyopathy (ARVC): Arrhythmogenic right ventricular cardiomyopathy (ARVC, formerly known as arrhythmogenic right ventricular dysplasia or ARVD) is a genetic disease that can be passed through families. Having a parent with ARVC increases the risk of developing the condition. ARVC occurs in men three times more often than in women; however, it is unclear why more men are affected. Physical activity may increase the risk of arrhythmia (abnormal heart beat) in ARVD.
Dilated cardiomyopathy: Because there are multiple factors (primary or secondary) that can cause the different forms of dilated cardiomyopathy, there are also many different risk factors. For the most common form of dilated cardiomyopathy, ischemic cardiomyopathy, major risk factors are coronary artery disease (CAD) and high blood pressure. However, viral infections, other heart diseases, or genetics may also increase the risk of ischemic cardiomyopathy. For peripartum cardiomyopathy that occurs in women during the last month of pregnancy or first five months following birth, risk factors include obesity, pregnancy-induced hypertension (preeclampsia), multiple pregnancy (such as twins or triplets), or being more than 30 years of age. Women who have previously had peripartum cardiomyopathy are also at increased risk of developing cardiomyopathy with future pregnancies. Physical or emotional stress may worsen (or even cause) cardiomyopathy. Excessive alcohol consumption may also increase the risk of dilated cardiomyopathy.
Hypertrophic cardiomyopathy (HCM): Like ARVC, hypertrophic cardiomyopathy (HCM) is also a genetic disease that is inherited. Having a parent with the condition increases the risk of developing HCM. While HCM is often asymptomatic (without symptoms), physical activity greatly increases the risk of complications (e.g., atrial fibrillation) and death, due to HCM.
Restrictive cardiomyopathy: Restrictive cardiomyopathy is usually secondary to another acquired or inherited heart disease (such as amyloidosis, endomyocardial fibrosis, or sarcoidosis). It may also occur after a heart transplant. Having any disease or injury that affects the heart muscle may increase the risk of restrictive cardiomyopathy. Having a parent with the condition increases the risk of heritable forms of restrictive cardiomyopathy.

Types of the disease

There are four main types of cardiomyopathy as defined by the American Heart Association (AHA): arrhythmogenic right ventricular cardiomyopathy (ARVC), dilated cardiomyopathy, hypertrophic cardiomyopathy (HCM), and restrictive cardiomyopathy. Dilated cardiomyopathy may result from multiple causes and is the most common form of cardiomyopathy that affects the overall population of North America. HCM is genetic in origin, and is the most common cause of sudden death in athletes. Restrictive cardiomyopathy and ARVC are considered to be rarer forms of the disease.
The different types of cardiomyopathy are further classified by the AHA as primary or secondary. Primary cardiomyopathies cannot be attributed to other conditions (such as heart disease). Instead, they may be caused by genetic (inherited) factors, acquired factors, or a combination of genetic and acquired traits. Acquired causes of cardiomyopathy include inflammatory cardiomyopathy (myocarditis), post- or peripartum cardiomyopathy, and stress cardiomyopathy (broken heart syndrome). Secondary cardiomyopathy occurs as a result of another condition, such as an infection or a metabolic disease (e.g., diabetes or coronary heart disease).
Arrhythmogenic right ventricular cardiomyopathy (ARVC): Arrhythmogenic right ventricular cardiomyopathy (ARVC, formerly known as arrhythmogenic right ventricular dysplasia or ARVD) is a genetic disease that causes the myocardium to become fatty and fibrous. Though it mainly affects the right ventricle of the heart, it may also affect the left ventricle. In contrast to other forms of cardiomyopathy, ARVC seldom results in heart failure. However, it does cause abnormal heart function such as arrhythmia (abnormal heartbeat), which may be fatal.
Dilated cardiomyopathy: In dilated cardiomyopathy, the myocardium becomes weak, enlarged, and unable to pump blood efficiently. The prevalence of dilated cardiomyopathy in the United States is 36 per 100,000. It is considered the most common form of cardiomyopathy. After coronary artery disease (CAD) and hypertension (high blood pressure), dilated cardiomyopathy is the third most common cause of heart failure in the United States.
There are several types of dilated cardiomyopathy, which are caused by multiple factors (primary or secondary). The three types of dilated cardiomyopathy include ischemic cardiomyopathy, peripartum cardiomyopathy, and stress cardiomyopathy.
Ischemic cardiomyopathy is the most common form of dilated cardiomyopathy. It is most often caused by CAD or high blood pressure; however, viral infections, other heart diseases, or genetics may also contribute to ischemic cardiomyopathy.
Peripartum cardiomyopathy is usually diagnosed in women in their last month of pregnancy, or in the first five months following birth (also called postpartum cardiomyopathy). Although it is rare (affecting one in 1,000-4,000 live births), peripartum cardiomyopathy is more prevalent in women who are over age 30, obese, have pregnancy-induced hypertension (preeclampsia), or multiple births.
Excessive alcohol use may also cause dilated cardiomyopathy.
Hypertrophic cardiomyopathy (HCM): In hypertrophic cardiomyopathy (HCM), the myocardium is thickened. As a result, it becomes difficult for the heart to pump blood. Nearly one-half of deaths due to HCM occur during or after physical activity. Sudden death occurs due to lethal heart rhythm disturbances (ventricular fibrillation and ventricular tachycardia). It is the most common cause of sudden cardiac death in athletes as a result of structural heart changes in response to intense training. Because HCM is typically an inherited disorder, it is also called familial HCM. It is estimated that one of 500 people has the gene for HCM. However, it may also be acquired resulting from high blood pressure or aortic stenosis (narrowing or obstruction of the aortic valve causing restricted blood flow). Symptoms of HCM include chest pain, shortness of breath, dizziness, palpitations, and fatigue.
Restrictive cardiomyopathy: In restrictive cardiomyopathy, the heart is unable to function properly, due to stiffness of the myocardium. The heart is usually normal size (or slightly larger), but the myocardium of one or both ventricles (cavities or chambers) cannot relax after each heartbeat because of stiffness in the heart. Instead, the ventricles are restricted and do not fill with enough blood. Restrictive cardiomyopathy may have a genetic cause, or it may result from another myocardial disease.
Other: Stress cardiomyopathy (also known as broken heart syndrome or Takotsubo cardiomyopathy) is triggered by sudden intense physical or emotional stress (e.g., death of a loved one, fear, extreme anger). The clinical presentation is similar to that of a heart attack. The most common symptoms are chest pain, shortness of breath, and low blood pressure.