Heart failure is a serious condition in which the muscle is not able to pump enough blood to meet the body's demands. According to Dr. Leonard S. Lilly, author of "Pathophysiology of Heart Disease," the most common causes of heart failure are coronary artery disease, high blood pressure, heart valve disease and diabetes. The Centers for Disease Control and Prevention states 5.8 million people in the United States suffer from the different forms of heart failure. Heart failure is divided into five main classes.
Chronic and Acute Heart Failure
In chronic heart failure, the patient's body adapts to the reduced output of blood from the heart through changes such as enlargement of the bottom left heart chamber. These adaptations make the condition less difficult and more tolerable for the body to handle. More severe, acute heart failure involves an immediate reduction in blood flow to vital organs and congestion of the heart, possibly leading to complete heart failure.
Left-Sided and Right-Sided Heart Failure
Heart failure usually occurs on one side after a heart attack. Left untreated, failure of both sides will eventually follow, especially when failure starts on the left side. That's because when one side of the heart enlarges because of heart failure, the other side becomes compressed and starts losing it ability to function as a result, says Dr. Michael H. Crawford, author of "Current Diagnosis and Treatment in Cardiology."
High-Output and Low-Output Heart Failure
Heart failure that results in a reduced amount of blood pumped from the heart, referred to as low-output state, is common. Less common is high-output failure or increased blood flow from the heart, and that is associated with having other conditions, such as anemia or thyrotoxicosis, according physician-author Crawford.
Backward and Forward Heart Failure
Backward heart failure involves blood being forced back into one or both sides of the heart as a result of increased pressure on the heart's chambers. Doctors believe backward failure occurs when right-side failure develops after left-side failure, according to physician-author Lilly. Forward heart failure is more common, and involves blood flowing forward from the heart, though at a significantly reduced output.
Systolic and Diastolic Heart Failure
In systolic heart failure, the heart's ability to pump blood is compromised, resulting in less output. Weakened or compressed heart chambers can cause this condition. Diastolic heart failure occurs when the heart cannot properly fill with blood, also leading to decreased output. Caused by physical exertion, in which not enough blood is returning to the heart, this form is more common. Cardiologist Crawford, a professor of medicine at the the University of California at San Francisco, says 40 percent of all patients with diagnosed heart failure have signs of diastolic failure.
References
- Centers for Disease Control and Prevention: Heart Failure Fact Sheet
- "Pathophysiology of Heart Disease"; Congestive Heart Failure; Leonard S. Lilly, M.D.; 2007
- "Current Diagnosis and Treatment in Cardiology"; Congestive Heart Failure; Michael H. Crawford, M.D.; 2009
