Ischemic cardiomyopathy

Answer 1

Definition

Ischemic cardiomyopathy is a term that doctors use to describe patients who have reduced heart pumping (squeezing) due to coronary artery disease. These patients often have congestive heart failure.

"Ischemic" means that an organ (such as the heart) is not getting enough blood and oxygen. "Cardio" means heart and "myopathy" means muscle-related disease.

See also:

• Angina
• Coronary artery disease
• Heart failure

Alternative Names

Ischemic Heart disease; Cardiomyopathy - ischemic

Causes, incidence, and risk factors

Ischemic cardiomyopathy results when the arteries that bring blood and oxygen to the heart are blocked. There is usually a buildup of cholesterol and other substances, called plaque, in the arteries that bring oxygen to heart muscle tissue. Over time, the heart muscle does not work well, and it is more difficult for the heart to fill and pump blood to the body.

Ischemic cardiomyopathy is a common cause of congestive heart failure. Patients with this condition may at one time have had a heart attack, angina, or unstable angina. A few patients may not have noticed any previous symptoms.

Ischemic cardiomyopathy is the most common type of cardiomyopathy in the United States. It affects approximately 1 out of 100 people, most often middle-aged to elderly men.

Risks for this condition include:

• Diabetes
• High blood pressure
• High cholesterol
• High-fat diet
• Obesity
• Personal or family history of heart attack, angina, unstable angina, atherosclerosis, or other coronary artery diseases
• Sedentary lifestyle
• Smoking

Symptoms

Patients with ischemic cardiomyopathy often have symptoms of angina or heart failure.

Symptoms of angina include:

• Chest pain that occurs behind the breastbone or slightly to the left of it. It may feel like tightness, heavy pressure, squeezing, or crushing pain. The pain may spread to the neck, jaw, back, shoulder, or arm.
• Dizziness or light-headedness
• Feeling of indigestion or heartburn
• Nausea, vomiting, and cold sweats
• Sensation of feeling the heart beat (palpitations)
• Shortness of breath
• Unexplained tiredness after activity (more common in women)

Symptoms of heart failure usually develop slowly over time. However, sometimes symptoms start very suddenly and are severe. Common symptoms include:

• Awakening from sleep after a couple of hours due to shortness of breath
• Cough
• Fatigue, weakness, faintness
• Loss of appetite
• Pulse may feel irregular or rapid, or there may be a sensation of feeling the heart beat (palpitations)
• Shortness of breath, especially with activity
• Shortness of breath that occurs after lying down
• Swelling of feet and ankles (in adults)
• Swelling of the abdomen (in adults)

Signs and tests

The physical examination may be normal, or it may reveal signs of fluid buildup:

• "Crackles" in the lungs (heard with a stethoscope)
• Elevated pressure in the neck vein
• Enlarged liver
• Extra heart sounds
• Leg swelling

There may be other signs of heart failure.

This condition is usually diagnosed only if a test shows that the pumping function of the heart is too low. This is called a decreased ejection fraction. A normal ejection fraction is around 55 - 65%. Most patients with this disorder have ejection fractions much less than this.

Ischemic heart disease can make people more likely to have heart failure and the symptoms and signs noted above when the ejection fraction is normal or near normal. This is due to the abnormal relaxation of the heart (impaired filling). This is sometimes called "diastolic heart failure" or "heart failure with preserved ejection fraction."

Tests used to measure ejection fraction include:

• Echocardiogram
• Gated SPECT
• MRI of heart
• Ventriculogram performed during a cardiac catheterization

Biopsy of the heart is needed in rare cases to rule out other disorders.

Lab tests that may be used to rule out other disorders and assess the condition of the heart include:

• Blood chemistries
• Cardiac biochemical markers (CK-MB, troponin)
• CBC
• Coronary risk profile (including blood lipid levels)

Treatment

The goal of treatment is to relieve symptoms and treat the cause of the condition. If symptoms are severe, you may need to stay in the hospital.

A cardiac catheterization might be done to see if you may benefit from coronary artery bypass (CABG) surgery or a balloon procedure (angioplasty), which could improve blood flow to the damaged or weakened heart muscle.

The overall treatment of cardiomyopathies is focused on treating heart failure.

See also: Heart failure

Drugs and treatments that may be used include:

• ACE inhibitors such as captopril, enalapril, lisinopril, and ramipril
• Angiotensin receptor blockers (ARBs) such as losartan and candesartan
• Diuretics, including thiazide, loop diuretics, and potassium-sparing diuretics
• Digitalis glycosides
• Beta-blockers such as carvedilol and metoprolol
• Drugs that dilate blood vessels (vasodilators), such as isosorbide dinitrate or hydralazine

Some people may benefit from the following heart devices:

• Single or dual chamber pacemaker
• Biventricular pacemaker
• Implantable cardioverter-defibrillator
• Left ventricular assist device (LVAD)

A low-salt diet may be prescribed for adults. Fluid may be restricted in some cases. You can usually continue your regular activities, if you are able.

If you smoke or drink alcohol excessively, stop doing so. These habits increase stress on the heart.

You may be asked to monitor your body weight daily. Weight gain of 3 or more pounds over 1 or 2 days may indicate fluid buildup (in adults).

A heart transplant may be recommended for patients who have failed all the standard treatments and still have very severe symptoms. Recently, implantable, artificial heart pumps have been developed. However, very few patients are able to undergo either of these advanced treatments.

Expectations (prognosis)

This is a very serious disorder. It is a chronic illness that usually gets worse over time. Infection and other stress on your body from other medical illnesses will also cause symptoms to get worse.

It is very important to discuss your situation with your doctor to ensure that you can improve it as much as possible. You can control symptoms of heart failure and angina with medication, lifestyle changes, and by treating any underlying disorder.

Complications

• Arrhythmias, including lethal arrhythmias
• Cardiogenic shock

Calling your health care provider

Go to the emergency room or call 911 if:

• You have symptoms of ischemic cardiomyopathy
• You have chest pain that is not relieved by rest or nitroglycerin
• You pass out (syncope)

Prevention

The best way to prevent ischemic cardiomyopathy is to avoid getting heart (cardiovascular) disease (for example, high blood pressure and coronary artery disease).

• Avoid excessive drinking
• Eat a healthy diet
• Exercise as much as possible
• Maintain a healthy weight
• See your doctor to control blood pressure, cholesterol, and Diabetes
• Stop smoking

References

Hunt SA, Abraham WT, Chin MH, et al. ACC/AHA 2005 Guidelines Update for the Diagnosis and Management of Chronic Heart Failure in the Adult: a report of the American College of Cardiology/American Heart Association Task Force on Practice Guidelines (Writing Committee to Update the 2001 Guidelines for the Evaluation and Management of Heart Failure): developed in collaboration with the American College of Chest Physicians and the International Society for Heart and Lung Transplantation: endorsed by the Heart Rhythm Society. Circulation. 2005;112:e154-e235.

Dickstein K, Cohen-Solal A, Filippatos G, et al. ESC Guidelines for the diagnosis and treatment of acute and chronic heart failure 2008: the Task Force for the Diagnosis and Treatment of Acute and Chronic Heart Failure 2008 of the European Society of Cardiology. Developed in collaboration with the Heart Failure Association of the ESC (HFA) and endorsed by the European Society of Intensive Care Medicine (ESICM). Eur Heart J. 2008;29:2388-2442.

Hare JM. The dilated, restrictive, and infiltrative cardiomyopathies. In: Zipes DP, Libby P, Bonow RO, Braunwald E, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 8th ed. Philadelphia, Pa; Saunders Elsevier;2007:chap 64.

Answer 2

Definition

Ischemic cardiomyopathy is a term used to describe patients whose heart can no longer pump enough blood to the rest of their body due to coronary artery disease.

Coronary artery disease is a narrowing of the small blood vessels that supply blood and oxygen to the heart.

These patients often haveheart failure.

Alternative Names

Ischemic heart disease; Cardiomyopathy - ischemic

Causes, incidence, and risk factors

Ischemic cardiomyopathy is caused by coronary heart disease -- the buildup of a hard substance called plaque in the arteries to the heart. This may also be called hardening of the arteries.

When the arteries that bring blood and oxygen to the heart are blocked or very narrowed, over time, the heart muscle does not work as well. It becomes harder for the heart to fill and pump blood to the body. Patients with this condition usually have a history of heart attacks or angina (chest pain).

Ischemic cardiomyopathy is a common cause of heart failure. It is the most common type of cardiomyopathy in the United States. It most often affects middle-aged and elderly people.

For risk factors, see: Coronary heart disease

Symptoms

Patients with this condition often have had symptoms of angina or a heart attack. Sometimes, patients do not notice any symptoms.

Symptoms of heart failure usually develop slowly over time. Common symptoms include:

• Cough
• Fatigue, weakness, faintness
• Irregular or fast pulse, or a sensation of feeling the heart beat (palpitations)
• Loss of appetite
• Shortness of breath, especially with activity
• Shortness of breath that occurs after lying down
• Swelling of feet and ankles (in adults)
• Swelling of the abdomen (in adults)
• Waking up from sleep after a couple of hours due to shortness of breath

Signs and tests

The physical exam may be normal, or there may be signs that fluid is building up in the body:

• "Crackles" in the lungs (heard with a stethoscope)
• Enlarged liver
• Extra heart sounds
• Leg swelling
• Raised pressure in the neck vein

There may be other signs of heart failure.

This condition is usually diagnosed if a test shows that the heart is not pumping as well as it should. This is called a decreased ejection fraction. A normal ejection fraction is around 55 - 65%. Many patients with this disorder have ejection fractions much less than this.

People with ischemic heart disease can have the symptoms and signs of ischemic cardiomyopathy even when their ejection fraction is normal or near normal. This is because the heart does not fully relax (impaired filling). It is sometimes called "diastolic heart failure" or "heart failure with preserved ejection fraction."

Tests used to measure ejection fraction include:

• Echocardiogram
• Gated SPECT
• MRI of heart
• Ventriculogram or cardiac blood pooling imaging

Biopsy of the heart is needed in rare cases to rule out other conditions.

Treatment

To treat ischemic cardiomyopathy, your doctor will treat and manage your heart failure by:

• Showing you how to make important changes in your lifestyle
• Teaching you about the symptoms of heart failure
• Giving you medicines for heart failure
• Giving you a pacemaker to help treat a slow heart rate or help the heart beat in a more normal way
• Implanting a defibrilator, which recognizes abnormal heart rhythms and sends an electrical pulse to stop them

See also: Heart failure

A cardiac catheterization might be done to see if you need coronary artery bypass(CABG) surgery or a balloon procedure (angioplasty). These procedures can improve blood flow to the damaged or weakened heart muscle.

You may need a heart transplant if you have tried all the standard treatments and still have very severe symptoms. Implantable, artificial heart pumps are now available. However, very few patients are able to have these advanced treatments.

Expectations (prognosis)

Often, heart failure can be controlled with medicine, lifestyle changes, and by treating the disease that caused it.

Heart failure may suddenly become worse due to angina, heart attack, infections, other illnesses, eating foods that high in salt, and not taking medicines correctly.

Heart failure is usually a long-term (chronic) illness. It may get worse over time.

Some people develop severe heart failure. Medicines, surgery, and other treatments no longer help. They are at risk for dangerous heart rhythm problems.

Calling your health care provider

Go to the emergency room or call 911 if:

• You have symptoms of ischemic cardiomyopathy
• You have chest pain that is not relieved by rest or nitroglycerin
• You pass out (syncope)

Prevention

Some of the risks for heart disease that you CAN change are:

• Do not smoke or use tobacco.
• Get plenty of exercise -- at least 30 minutes a day, at least 5 days a week (talk to your doctor first)
• Stay at a healthy weight. Try for a body mass index (BMI) of between 18.5 and 24.9.
• Get checked and treated for depression.
• Women at high risk for heart disease should take omega-3 fatty acid supplements.

If you drink alcohol, limit yourself to no more than one drink a day for women, and no more than two drinks a day for men. Because alcohol in large amounts can be toxic to the heart, you may be asked to limit your alcohol even more, or stop drinking it completely.

Good nutrition is important for your heart health and will control some of your risk factors. See also: Heart disease and diet

References

Morrow DA, Boden WE. Stable ischemic heart disease. In: Bonow RO, Mann DL, Zipes DP, Libby P, eds. Braunwald's Heart Disease: A Textbook of Cardiovascular Medicine. 9th ed. Philadelphia, Pa; Saunders Elsevier;2011:chap 57.

Reviewed By

Review Date: 05/23/2011

Michael A. Chen, MD, PhD, Assistant Professor of Medicine, Division of Cardiology, Harborview Medical Center, University of Washington Medical School, Seattle, Washington. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.