Cardiomyopathy - ischemic

Definition

Ischemic cardiomyopathy is a term that doctors use to describe patients who have congestive heart failure due to coronary artery disease.

"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.

Alternative Names

Causes

Ischemic cardiomyopathy results when the arteries that bring blood and oxygen to the heart are blocked. There may be a build-up of cholesterol and other substances, called plaque, in the arteries that bring oxygen to heart muscle tissue.

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:

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

Symptoms

• Chest pain
  • Under the chest bone
  • May move (radiate) to the neck, jaw, back, shoulder, arm
  • May feel tight, pressure, crushing, squeezing
  • May or may not be relieved by rest or nitroglycerin
• Sensation of feeling the heart beat (palpitations)
• Irregular or rapid pulse
• Shortness of breath, especially with activity
• Shortness of breath that occurs after lying down for a while
• Cough
• Fatigue, weakness, faintness
• Decreased alertness or concentration
• Decreased urine output
• Excessive urination at night
• Overall swelling
• Breathing difficulty when lying down

Exams and Tests

The physical examination may be normal, or it may reveal signs of fluid buildup (leg swelling, enlarged liver, "crackles" in the lungs, extra heart sounds, or an elevated pressure in the neck vein). There may be other signs of heart failure

The diagnosis of this condition is usually made 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. Tests used to measure ejection fraction include:

• Echocardiogram
• Ventriculogram performed during a cardiac catheterization
• Gated SPECT
• MRI of chest
• ECG
• 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 to assess the condition of the heart include:

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

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.

Several types of medications have been found to help patients live longer with this disorder. They include ACE-inhibitors (captopril, lisinopril), beta-blockers (metoprolol, carvedilol), and diuretics such as furosemide (Lasix), spironolactone, and eplerenone.

A cardiac catheterization will be done to see if you can have bypass surgery or angioplasty ("balloon procedure"). These treatments can improve blood flow to the damaged or weakened heart muscle.

A number of studies have shown that heart failure symptoms can be improved with a special type of pacemaker. It paces both the right and left sides of heart. This is referred to as biventricular pacing or cardiac resynchronization therapy. Ask your provider if this therapy is right for you.

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. At this point, very, very few patients will be able to undergo either of these advanced treatments.

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

Outlook (Prognosis)

This is a very serious disorder. Patients with this condition, in general, do not have a normal lifespan. For some, the prognosis is just as bad as for many forms of cancer. Thus, it is very important to discuss your particular situation with your doctor to ensure that you can improve it as much as possible.

Possible Complications

• Arrhythmias, including lethal arrhythmias
• Cardiogenic shock

When to Contact a Medical Professional

Go to the emergency room or call 911 if you have symptoms that may be ischemic cardiomyopathy, or if chest pain is present and not relieved by rest or nitroglycerin.

Prevention

The best way to prevent ischemic cardiomyopathy is to avoid getting heart disease. Stop smoking, eat a healthy diet, maintain a healthy weight, exercise as much as possible, avoid excessive drinking, and see your doctor to control blood pressure, cholesterol, and diabetes.