What Is Heart Failure?

The heart is a muscular organ at the core of the circulatory system. Its four chambers — two upper and two lower — cycle blood and oxygen throughout your body.

When the heart's chambers cannot pump enough blood to meet the body's needs, the stage is set for heart failure, also called congestive heart failure. "Heart failure is a complicated syndrome, and it involves pretty much every organ in the body," explains Roger J. Hajjar, MD, Professor of Cardiology and Director of the Cardiovascular Research Center.

Systolic and Diastolic Heart Failure

Each time your heart beats, it pumps blood throughout your body. A normal heart pumps about 60 percent of its contents with each beat. The percentage of blood pumped in a heartbeat, called the ejection fraction, helps your doctor evaluate the type of heart failure you have.

Depending on when in the heart's cycle the trouble occurs, heart failure can be characterized as either systolic, or unable to squeeze blood out to the body, or diastolic, which is characterized by the inability to stretch well enough to fill with blood in preparation for the next heartbeat.

Causes of Heart Failure

Congestive heart failure may be caused by one or more conditions that weaken or damage the heart muscle or its vessels:

• High blood pressure, or hypertension
• Heart attack and coronary artery disease
• Heart infections or inflammations
• Heart valve disease
• Abnormal heart rhythms, or arrhythmia
• Congenital heart defects, which are conditions present at birth

Heart Failure Signs and Symptoms

Symptoms of heart failure depend on the progression of the condition. Chronic heart failure describes the long-term effects of the condition. Acute heart failure refers to the sudden onset of heart failure and is potentially life threatening.

Chronic heart failure symptoms are lasting and include:

• Fatigue
• Shortness of breath
• Swelling (edema) in the feet, ankles, and legs
• Irregular heartbeat

Acute heart failure symptoms are sudden and possibly life threatening. Symptoms include:

• Severe shortness of breath
• Rapid heartbeat and palpitations, which may cause the heart to stop beating
• Sudden fluid retention
• Sudden and severe chest pain

If any of these symptoms occurs, seek immediate medical attention.

Heart Failure Risk Factors

A single condition or several conditions over time can increase your risk of heart failure. Factors that increase your risk of heart failure include:

• Coronary artery disease
• High blood pressure (hypertension)
• Previous heart attack
• Obesity
• Diabetes
• Congenital defects
• Alcohol use
• Kidney disease