Congestive Heart Failure
Congestive heart failure (CHF), or cardiomyopathy, occurs when the pumping action of the heart has been weakened, causing shortness of breath, fatigue, and swelling, particularly in the legs and feet. There is decreased circulation to the major organs, and the kidneys retain more fluid to compensate. There are also neurohormonal factors that tend to stimulate or overdrive the heart. This ultimately can lead to further damage and deterioration of the heart function. Patients with functional class III to IV heart failure, where they are short of breath with low levels of activity or at rest, have a three- to four-year mortality rate of 35 to 45 percent. Mortality may be higher in older patients.
The most common cause of congestive heart failure is ischemic heart disease or prior myocardial infarctions. Older patients with congestive heart failure and coronary artery disease may benefit from revascularization, and they are at higher risk for silent ischemia or missed infarcts. While this accounts for 70 percent of the patients with congestive heart failure, there are numerous other causes, including hypertension, valvular heart disease, viral infection, and arrhythmias. Another age-related problem is chemotherapy (e.g., adriamycin, anthracycline, herceptin, taxanes, and others) for cancer.
With acute congestive heart failure, patients become suddenly short of breath, cannot lie flat, and develop edema. Patients in an emergency room will be treated with oxygen therapy as well as intravenous diuretics and nitroglycerin to help remove the fluid.
CHF can also be more insidious, with a gradual or progressive course of increasing shortness of breath over hours and days. This may be related to a change in fluid or salt intake. CHF patients require polypharmacy (the use of multiple medications, as heart patients often take anywhere from four to twelve drugs a day) to control their symptoms and improve survival. Angiotensin-converting enzyme (ACE) inhibitors have been shown to significantly reduce symptoms, hospitalizations, and mortality. For patients who are intolerant of ACE inhibitors, a reasonable next choice would probably be angiotensin receptor blockers (ARBs).
Beta blockers lower blood pressure, slow the heart rate, and decrease the heart's workload. Previously felt to worsen CHF, studies have shown that beta blockers actually improve survival, reduce symptoms, and improve heart function. Side effects may include fatigue or depression, and it is important that such side effects not be simply blamed on "old age."
Patients with severe heart failure (functional class III to IV) and an ejection fraction less than 30 percent should be treated with spironolactone. This medication is a diuretic with unique neurohormonal-blocking properties that have been shown to significantly reduce mortality. Other diuretics are also useful to help control symptoms of fluid retention.
Digoxin also reduces symptoms and decreases hospitalizations in heart failure. There are other inotropic medications available that make the heart stronger and can temporarily improve symptoms. Unfortunately, these medications decrease survival. Some patients with very severe CHF, however, may feel the benefit of fewer symptoms is worth the risk of not living as long as they would otherwise.
Certain medications are generally contraindicated in heart failure. Most calcium channel blockers worsen heart failure, though amilodipine and felodipine have been shown to be safe. Nonsteroidal anti-inflammatory drugs (NSAIDS) used to treat arthritis may also aggravate heart failure, as can alcohol, which should generally be avoided. Exercise is useful but must be individualized to a patient's physical state. Most lifestyle modifications are probably best coordinated through a heart function clinic run by nurse specialists.
Heart transplantation is an option only if patients have failed all other medical treatments and still have severe heart failure. It is also restricted to patients under sixty-five, as older patients do not do as well with the burden of aggressive immunosuppressive therapy.
- Heart Disease - Valvular Heart Disease
- Heart Disease - Ischemic Heart Disease
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