A - Z Encyclopedia

Understanding Heart Failure

the Basics

What Is Heart Failure?

Heart failure is a condition in which the heart can't pump blood effectively to the lungs or the rest of the body, usually because the person has narrowed or hardened coronary arteries (the vessels that supply blood to the heart muscle), has previously suffered a heart attack, or has high blood pressure.

With heart failure, the weakened heart pumps less blood than usual €” too little to push enough circulated blood back into the heart to repeat the journey. So blood stalls, or congests, in the body's tissues. This makes it even harder for the heart to push blood through the arteries on the next beat.

With congestion, the legs and ankles may swell. Fluid may also collect in the lungs and interfere with the ability to breathe, especially when lying down. The kidneys may have trouble disposing of sodium and water. Left untreated, heart failure worsens and may prevent the heart from pumping enough blood to keep the person alive.

Doctors divide heart failure cases into four levels of increasing severity:

• Class I: Physical activity is unaffected, and the patient has no unusual fatigue, shortness of breath, palpitations, or pain during normal activities.
• Class II: The patient may experience mild fatigue, shortness of breath, palpitations, or pain during normal activities; slight limitations on normal activities.
• Class III: The patient experiences fatigue, shortness of breath, palpitations, or pain during normal activities; activities are dramatically limited.
• Class IV: The patient is uncomfortable even at rest. Discomfort increases with any physical activity.

In some cases, medication and lifestyle changes enable patients to live nearly normal lives. Your outlook depends on how well your heart is functioning, your symptoms, and how well you respond to your treatment plan.

About 4.8 million Americans have heart failure, which contributes to about 287,000 deaths each year. Although treatment of heart failure has led to improved survival rates, as many as ten percent of patients with mild CHF and more than 50% of patients with more severe heart failure die annually. Heart failure is a growing public health concern worldwide. It is the single most frequent cause of hospitalization for Americans aged 65 and older.

What Causes It?

Many patients have both of the most common causes of heart failure:

• Coronary artery disease (narrowing or hardening of arteries that supply blood to the heart muscle, usually caused by a buildup of fats and cholesterol)
• High blood pressure (hypertension)

Heart failure may also be caused by other conditions that weaken or interfere with the heart, including:

• Previous heart attack
• Heart valve disease
• Damage to the heart muscle (cardiomyopathy)
• Heart defects present at birth
• Infection of the heart valves or muscle (endocarditis or myocarditis)
• Diabetes
• Chronic kidney disease

Back to eHealth Encyclopedia