Congestive heart failure (CHF) is the result of abnormal and depressed function of the heart for any reason. The most common presentations of this syndrome are the development of shortness of breath during exertion, rest, at night (called paroxysmal nocturnal dyspnea or PND), or upon lying down (called orthopnea). This may be associated with a chronic cough, fatigue or swelling (at the point of the most gravity, feet or the back if lying down) or weight gain. While chest pain may occur with this syndrome it is not a necessary component. These symptoms often develop slowly, but may occur quickly.
The incidence of CHF is on the rise, affecting five million people in the United States. The condition affects mostly older adults. Approximately eight out of 1,000 people over age 70 are diagnosed with CHF. It is one of the most common reasons for hospitalization in this age group. The rise in CHF is due to people living and surviving longer from cardiac problems and conditions that put them at risk for the development of CHF. The condition is treatable and its effects are often reversible.
How the heart works
The heart pumps oxygen and nutrients to the body's tissues and organs. It also helps rid the body of unnecessary waste products. The heart consists of four chambers, the right and left atria and the right and left ventricles. Blood from the body enters the heart through the right atrium to the right ventricle, which brings blood to the lungs. It is here that carbon dioxide is removed from the blood and oxygen is added. Blood then returns to the heart via the left atrium. The heart then pumps the oxygen-rich blood to the rest of the body through the left ventricle. The heart performs this task on an ongoing basis. Should the heart weaken for any reason, the circulation slows and things back up. If the left ventricle is weak (failing), fluid collects in the lungs. This causes a back up of fluid in the right side of the heart and ultimately the development of fluid in the legs.
CHF is not a disease in itself. It is a syndrome in which the heart is unable to pump an adequate supply of blood to meet the oxygen requirements of the body's tissues and organs. The weakening of the heart as a pump in heart failure results in slow blood flow out of the heart to the rest of the body. This causes back up of blood in those chambers in the heart that are weakened and the veins that return blood to the heart from the rest of the body. The pooling of blood in the veins leads to the congestion of surrounding tissues and organs and the development of congestive symptoms such as leg edema (or swelling), nausea and bloating due to bowel edema, and shortness of breath due to lung edema. The development of these CHF symptoms and others depends on the severity of the heart failure, the time it took to develop (suddenly or gradually), and quality of treatment.
CHF is a symptom of an underlying cardiovascular problem; the disease process is often identified as a result of the symptoms of CHF. The most common causes are:
Left-sided versus right-sided heart failure
CHF may occur in one or both sides of the heart. As one side of the heart begins to fail, the other side can continue to function normally. However, untreated one-sided CHF often leads to excessive strain and subsequent CHF on the other side. CHF usually begins with the left side of the heart and progresses backward until the right side, too, fails. The left side of the heart receives oxygen-rich blood from the lungs and pumps it to the rest of the body. When the left side of the heart begins to fail, blood flow backs up into the lungs. Forward blood flow to the rest of the body may be impeded as well. With right-sided failure, the heart is unable to effectively pump blood to the left side and blood flow backs up to other parts of the body, including the legs and feet, liver, and gastrointestinal tract. Some of the symptoms may overlap.
Physical examination and diagnostic tests
Your doctor will perform an extensive history and physical. The history is extremely important as it may give clues as to the cause. The physical examination will reveal signs such as a rapid or irregular heart rate; a rapid respiratory rate (e.g., how fast you breathe); abnormal breathing sound heard with a stethoscope and called rales made by fluid in the lungs, and heart sounds indicating abnormal function. Neck veins may be distended; feet or ankles may be swollen; liver may be enlarged.
Chest x-rays are useful for assessing heart enlargement and fluid accumulation within or around the lungs. Electrocardiograms (ECG or EKG) and echocardiograms rae done to search for a cause for the CHF. These tests are effective for assessing the development of arrhythmias and whether there is evidence of prior heart disease. Echocardiograms, in particular, assess valve and heart wall motion. Frequently, blood and urine tests are also ordered as part of the diagnostic evaluation. One test is called BNP (brain type naturetic peptide), a hormone produced by the heart when it is under stress from heart failure or some pulmonary (lung) conditions. Other tests called troponins are often done to find out if the heart is currently under stress from a heart attack or virus (low levels of BNP and troponins are usually present, but acute injury or failure causes rises). Thyroid function and other endocrine function as well as liver and kidney function will also be checked.
Occasionally other tests are necessary to determine the cause of the heart failure. These tests may include Cardiac catheterization to determine the severity of any valvular disease or coronary artery disease, nuclear imaging, computerized tomography (CT) scan, or magnetic resonance imaging.
Cardiologists classify the importance of a patient’s congestive heart failure on the basis of symptoms and cause. For symptoms the New York Heart Association (NYHA) classification is used:
Several treatment goals exist for the CHF patient. First, any underlying event that precipitated the heart failure condition should be treated. If an underlying condition is untreatable, then CHF therapy focuses on the alleviation of symptoms, reduction of further heart failure progression, and improvement in heart pumping efficiency. Treatment of CHF may entail hospitalization, initiation or adjustment of medications, surgery, and lifestyle modification. Appropriate CHF management demands the attention of a qualified health care professional.
Multiple medications are often required in the treatment of CHF. When taken consistently and exactly as prescribed, a well-tolerated regimen is highly effective at both alleviating symptoms and prolonging life. The mainstays of medical therapy include:
Some medications are reserved for in-hospital use only or during cases of severe, decompensated heart failure. These medications, which include intravenous vasodilators (e.g., nesiritide, nitrates) and intravenous inotropics (e.g., milrinone, dobutamine), are usually only prescribed by physicians specially trained in heart failure management. Physicians may also temporarily discontinue some orally prescribed medications during severe cases of symptomatic heart failure. Again, only a physician trained in heart failure management should advise the discontinuation of these medications. Often, treatment of the underlying cause will result in cessation of symptoms and prolongation of life. This is quite frequent when the cause is valvular and can be treated surgically. Some problems are self-limited as well.
Newer therapies also are available in specialized heart failure clinics. These may in some instances include special pacemakers for resynchronizing the heart or for changing heart rhythm. When necessary, there are also devices for heart assistance called left ventricular assist devices and in certain cases transplantation can be considered.
Hospitalization might be required if your symptoms are too severe or if you do not respond to initial forms of treatment. Surgery may be indicated for some patients.
Lifestyle changes are important in the treatment of CHF. They include dietary restriction of sodium (salt), smoking cessation, limiting the consumption of alcohol and fluids, exercise and weight control. All lifestyle modifications must be monitored by appropriate medical personnel.
Relief and prevention
There are many therapeutic measures you can follow each day to help relieve and prevent the progression of CHF. Some of these are:
Know the signs and symptoms of CHF and immediately report any to your physician: edema, increased shortness of breath, distended neck veins, weight gain (as defined by your physician), persistent cough, and increased urination at night.
CHF is a disorder that can lead to serious complications and death. For this reason, it is important to know CHF warning signs and to follow your physician's plan of care. Symptoms can be controlled with appropriate treatment and the correction of underlying health problems.Sources
Mehra MR, MD, Associate Editor, HeartInfo, Head, Section of Heart Failure and Heart Transplantation, Department of Cardiology, Ochsner Medical Institutions, New Orleans, LA, Director, Ochsner Cardiomyopathy and Cardiac Transplantation Center, Ochsner Heart and Vascular Institute, Program Director, Cardiac Transplant Program, Ochsner Multi-Organ Transplant Center.
Client Teaching Guides For Home Health Care – Aspen Publishers, 1989.
Soufer R, MD. Treating a Sick Heart. Heart Disease. Yale University School of Medicine, 1992.
Congestive Heart Failure – What Happens When Your Heart Can’t Keep Up? Mayo Clinic Health Letter, July 1997.
Tolman D, MD, Congestive Heart Failure Program – MCV Hospitals.