Congestive heart failure is generally a progressive disease with periods of stability punctuated by episodic clinical exacerbations. The course of the disease in any given patient, however, is extremely variable. Factors involved in determining the long term outlook (prognosis) for a given patient include :
- the nature of the underlying heart disease,
- the response to medications,
- the degree to which other organ systems are involved and the severity of other accompanying conditions,
- the patient's symptoms and degree of impairment, and
- other factors that remain poorly understood.
With the availability of newer drugs to potentially favorably affect the progression of disease, the prognosis in congestive heart failure is generally more favorable than that observed just 10 years ago. In some cases, especially when the heart muscle dysfunction has recently developed, a significant spontaneous improvement is not uncommonly observed, even to the point where heart function becomes normal.
An important issue in congestive heart failure is the risk of heart rhythm disturbances (arrhythmias). Of those deaths that occur in patients with congestive heart failure, approximately 50% are related to progressive heart failure. Importantly, the other half are thought to be related to serious arrhythmias. A major advance has been the finding that non surgical placement of automatic implantable cardioverter /defibrillators (AICD) in patients with severe congestive heart failure (defined by an ejection fraction below 30%-35%) can significantly improve survival, and has become the standard of care in most such patients.
Common Causes of Congestive Heart Failure
Many disease processes can impair the pumping efficiency of the heart to cause congestive heart failure. In the United States, the most common causes of congestive heart failure are :
- coronary artery disease,
- high blood pressure (hypertension),
- longstanding alcohol abuse, and
- disorders of the heart valves.
Less common causes include viral infections of the stiffening of the heart muscle, thyroid disorders, disorders of the heart rhythm, and many others.
It should also be noted that in patients with underlying heart disease, taking certain medications can lead to the development or worsening of congestive heart failure. This is especially true for those drugs that can cause sodium retention or affect the power of the heart muscle. Examples of such medications are the commonly used non steroidal anti inflammatory drugs (NSAIDs), which include ibuprofen (Motrin and others) and naproxen (Aleve and others) as well as certain steroids, some diabetic medication, and some calcium channel blockers.
