Congestive Heart Failure
- heart failure
- left-sided heart failure
Congestive heart failure, also known as CHF, is a condition in which a weakened heart cannot pump enough blood to body organs. Since the pumping action of the heart is reduced, blood backs up into certain body tissues.
What is going on in the body?
CHF can be caused by any of a number of complex problems that cause the pumping chambers of the heart to fail.
The heart is divided into a left heart and right heart. In a healthy heart, the right heart receives oxygen-poor blood from the body and pumps it to the lungs. The blood receives a fresh supply of oxygen as it passes through the lungs. The oxygen-rich blood is then pumped back into the left heart, which pumps it out to the rest of the body.
If the pumping chambers of the heart do not function well, blood becomes "backed up"in the lungs or in the tissues of the body, making them congested with blood and fluid. This is the basis for the name congestive heart failure. In time, the organs and tissues begin to suffer from not getting enough blood and oxygen.
What are the causes and risks of the condition?
CHF can be caused by many diseases and conditions. Coronary heart disease, abbreviated as CHD, is a major cause of CHF. Multiple or severe heart attacks can lead to CHF as heart muscle is damaged. Other risk factors for CHF include:
certain infectious diseases common in underdeveloped countries
congenital heart disease, which are heart defects present at birth
heart valve damage, such as the scarring from a heart valve infection known as endocarditis
high blood pressure
high cholesterol levels
an inactive lifestyle
- some genetic disorders that lead to heart muscle weakness or malfunction
What can be done to prevent the condition?
Prevention of CHF is not always possible. In some cases, controlling the conditions that lead to heart damage can help prevent its progress. For example, effective treatment of high blood pressure
can help reduce the risk of CHF. Other prevention measures include:
- avoiding excess alcohol
- eating a diet designed to reduce heart disease
- getting regular physical activity
- quitting smoking, for people who smoke
- keeping weight in a healthy range
How is the condition diagnosed?
The diagnosis of CHF begins with a careful medical history and physical exam.
CHF can be confirmed by an echocardiogram, which uses ultrasound waves to create a picture of heart muscle and valve function. Nuclear medicine scans may also be ordered.
Cardiac catheterization, is a more invasive procedure that gives a view of the blood flow through the heart. Doctors may also use blood tests to diagnose and to guide treatment.
Long Term Effects
What are the long-term effects of the condition?
Left untreated, CHF can cause poor health and early death. But, new advances in treatment can help delay its progress and decrease symptoms.
What are the risks to others?
CHF is not contagious and poses no risk to others.
What are the treatments for the condition?
Many medicines are used to treat CHF, including:
Angiotensin-converting enzyme inhibitors, also known as ACE inhibitors or ACEIs. These medicines help reduce the work-load on the heart. Examples of ACE inhibitors include enalapril (i.e., Vasotec), fosinopril (i.e., Monopril), or lisinopril (i.e., Prinivil, Zestril).
Angiotensin-receptor blockers (ARBs), such as valsartan (i.e., Diovan) and candesartan (i.e., Atacand), which have similar actions to the ACE inhibitors, and which can be substituted for the ACE inhibitors in the event of a dry cough.
Beta-adrenergic blockers, metoprolol (i.e Lopressor, Toprol XL), carvedilol (i.e., CoReg) or bisoprolol (i.e., Zebeta). These medicines help reverse some of the damage to the heart muscle that occurs in heart failure.
Beta-adrenergic blockers, ACE inhibitors and angiotensin-receptor blockers have all been shown to prolong survival and reduce complications of CHF and may be combined with one another depending on patient-specific factors.
Digoxin (i.e., Lanoxin). This type of medicine the heart muscles beat more strongly.
Diuretics. Also known as water pills, this type of medicine helps relieve the buildup of fluid in the tissues. Examples include furosemide (i.e., Lasix), metolazone (i.e., Zaroxolyn), spironolactone (i.e., Aldactone), or triamterene-HCTZ (i.e., Dyazide).
- Vasodilators such as hydralazine, prazosin (i.e., Minipress), or isosorbide dinitrate (i.e., Dilatrate, Isordil)..
In severe cases, implantable cardiac resynchronization devices can be used. This device stimulates the ventricles, which are the lower chambers of the heart. The device controls the beating of the ventricles so that they beat at the same time. Blood is pumped more efficiently, helping to reduce the effects of CHF.
A left ventricular assist device, called an LVAD, may also be used in severe cases of CHF. An LVAD is a small pump that helps the left ventricle pump more blood through the body. It is generally used to support a person until a heart transplant can be performed.
For some people, a heart transplant is the only treatment that can cure the CHF.
What are the side effects of the treatments?
Side effects vary with the medicines used:
Diuretics can cause dehydration, salt imbalance and low potassium.
ACE inhibitors can cause a chronic dry cough and rarely, a specific type of allergic reaction called angioedema.
Too much digoxin can cause serious side effects. These may include vomiting, visual impairment and heart rhythm disturbances.
Beta-blockers can cause some mild confusion, dizziness upon standing and fatigue. These side effects are worse when the medicine is first started and generally resolve with time.
What happens after treatment for the condition?
Most people with CHF will benefit if they exercise regularly. Every effort should also be made to reduce his or her coronary risk factors.
These actions may include:
The healthcare professional may need to adjust the medications until the person achieves the best response.
How is the condition monitored?
Periodic exams, blood tests, and imaging studies such as echocardiography are used to monitor CHF. Any new or worsening symptoms should be reported to the healthcare professional.