What is congestive heart failure?
Congestive heart failure (CHF) is a condition which results either from the inability of the heart to fill normally with blood (diastolic heart failure), or the inability of the heart to pump blood normally (systolic heart failure). CHF is typically characterized by symptoms such as shortness of breath, fatigue and inability to exercise, and fluid retention with leg swelling. These symptoms can be mild, and evident only at extreme levels of exertion, or severe, occurring at rest and interfering with daily life. Usually, symptoms develop slowly, as the heart gradually weakens and the body’s own compensatory adjustments become inadequate. Less commonly, however, heart failure can develop suddenly, and result in severe shortness of breath, weakness, or collapse, requiring emergent hospitalization.
What are the symptoms of congestive heart failure?
Patients with heart failure can experience a variety of symptoms. Weakness, lightheadedness, or dizziness, fatigue, or inability to exercise can be manifestations of low cardiac output. A rapid heart rate even while resting may be present. The body may retain fluid, especially in the legs and abdomen, and cause weight gain and abdominal distension. Backup of fluid into the lungs may cause shortness of breath, cough, and congestion. Difficulty lying flat in the bed, and waking up in the middle of the night with air hunger are common signs of heart failure. Loss of appetite and feelings of nausea may also be seen.
What causes congestive heart failure?
Heart failure results from other diseases which damage the heart, or which interfere with its ability to fill and empty normally. It may be due to heart muscle disease (cardiomyopathy), valvular disease, high blood pressure, recent or previous heart attack (coronary artery disease), or arrhythmia. Less commonly, it can be caused by thickening of the sac around the heart (pericarditis). Often, these diseases can be recognized and treated before heart failure develops, thus delaying or preventing the occurrence of this syndrome. Identifying these diseases early is important to make sure that permanent damage does not occur.
Some examples of these diseases include:
High blood pressure: because the heart has to work harder to overcome the elevated pressure and resistance in the body’s arteries, its pumping function eventually declines. At first, this is a reversible problem, but eventually, it can cause permanent damage to the heart muscle.
Coronary artery disease: When the blood vessels which “feed” the heart muscle with oxygen and other important nutrients are clogged by atherosclerosis, the heart does not function well, and can become temporarily, or permanently damaged. A heart attack (also called a myocardial infarction) can occur when one of the coronary artery closes off entirely, and causes severe and usually permanent damage to the heart muscle. A large heart attack can damage so much heart muscle that heart failure ensues.
Valvular disease: Heart valve damage can occur from aging, high blood pressure, infection, heart attack, or rheumatic fever. When the cardiac valves are damaged, they can become leaky, or rigid and immobile, creating extra work for the heart muscle which must try to maintain blood flow to the brain and other organs of the body. This extra work can overload the heart as a pump, and eventually, lead to heart failure.
Cardiomyopathy: Diseases of the heart muscle (see cardiomyopathy) can result in an enlarged, poorly contracting pump which cannot provide adequate forward blood flow to vital organs, or can result in a thick-walled pump which is difficult to fill and creates a backup of blood under pressure in the lungs or in the lower extremities.
How is heart failure diagnosed?
The diagnosis of heart failure is made based on findings from a person’s description of their symptoms, the results of a physical examination, and certain diagnostic tests, which may include blood tests, chest xray, ultrasound of the heart (see echocardiography), and EKG. Further testing to find the cause of heart failure may include stress testing and cardiac catheterization.
How is heart failure treated?
Regardless of the cause, the treatment of heart failure usually involves diet to restrict the amount of salt and water you take in, medication to remove fluid from the body (diuretics), medications to strengthen the force of the heart’s contractions (digitalis), and medication to reduce the work of the heart trying to empty into the arterial circulation. Depending on the cause of heart failure, treatment may also involve trying to improving the blood supply to the heart muscle by angioplasty or coronary artery bypass surgery, and repairing or replacing leaky or blocked cardiac valves. In some patients, treatment may include implantation of a defibrillator, to prevent from life threatening abnormal heart rhythms. Lastly, heart failure may be so severe that cardiac transplantation must be considered. Most important is that you have a close relationship with your heart failure doctors and nurses, to help monitor your response to treatment, and to support and advise you in all the aspects of your care.