Congestive heart failure refers to failure or inability of the heart to sufficiently meet the requirements of the varied tissues and organs in the body for nutrients and oxygen. Such lowering of the cardiac output is characterized by decreased quantities of blood being pumped by the heart, which in turn is insufficient for circulation of blood from the lungs and body to the heart, eventually leading to leakage of fluids from the capillary blood vessels.
- The main symptom of congestive heart failure is dyspnea or breathlessness.
- Shortness of breath may occur with exertion or activity; during rest; when lying flat; or it may wake up an affected person from sleep.Breathlessness may arise due to inefficient heart function which prevents it from pumping sufficient blood during times of stress or activity, or it may be caused due to collection of fluids/water in the lungs.
- Angina or chest pain. It may be observed if congestive heart failure is caused due to an underlying case of atherosclerotic heart disease.
Congestive heart failure can be caused due to many possible reasons. It may arise due to heart’s inability to squeeze correctly, damage to the heart structure, lung diseases, drugs or medicines that affect cardiac functionality, or other pre-existing medical disorders. A patient may suffer from more than one cause at the same time.
Any anomaly which can adversely affect the stroke volume, heart rate, and ejection fraction can result in inefficient pumping of the heart. This can lead to backing up of blood into veins that come to the heart, elevated pressure in the tiny capillaries, and leakage of water and other fluids into the interstitial area. Thus, decrease in cardiac output causes increased pressure in the tiny blood vessels, resulting in water leakage and onset of congestive heart failure symptoms.
The most common cause of congestive heart failure is weakening of the left ventricle muscles which in turn lower the ejection fraction and stroke volume. Heart muscle may become weak due to the following reasons:
- Presence of myocarditis, wherein the heart muscle experiences inflammation due to varied reasons like infection. Irritation or inflammation of the cardiac muscle limits its ability to squeeze and pump blood.
- Presence of diseased heart valves due to insufficiency or stenosis can hamper the in-out flow of blood to the heart. Mitral insufficiency refers to leakage in valve connecting the left ventricle to left atrium, while aortic stenosis refers to constriction of the valve that goes from the left ventricle to the aorta.
- Anomalies of the heart rhythm can also lower ejection fraction and lead to congestive heart failure.
- Presence of atherosclerotic heart disease, a condition characterized by narrowing of the coronary arteries which carry oxygen to the heart muscle, increasing the risk to heart attack as well as forming scar tissue in place of some muscle.
- Presence of cardiomyopathies, a set of conditions identified by inability of the heart muscle to squeeze effectively. Dilated cardiomyopathy refers to enlargement of the heart along with stretching and damage of the cardiac muscle fibers leading to inefficient contraction of the heart muscle.Ischemic cardiomyopathy refers to a damaged heart caused due to atherosclerotic heart disease.Hypertrophic cardiomyopathyrefers to excessively thickened cardiac muscle which cannot squeeze properly.Idiopathic cardiomyopathy refers to cardiac conditions that have no known cause. Certain cardiomyopathies are caused due to cocaine/other drugs and/or alcohol abuse.
- Poorly managed diabetes and/or high blood pressure that leads to failure of the left ventricle.
Overexertion by the heart to pump against elevated resistance in the blood vessels that go to the lungs can cause right heart failure. Even though the right ventricle begins pumping harder to overcome the rise of pressure in the pulmonary veins and arteries, it may sometimes be in vain. Right heart failure may be caused due to:
- Elevated blood pressure in the pulmonary blood vessels.
- Presence of blood clot in blood vessels going to the lung.
- Constriction of the valve connecting the right ventricle and the pulmonary artery.
- Presence of chronic obstructive pulmonary disease.
Diseases affecting different body systems can alter the balance of water in the body or the overall supply/flow of oxygen, thereby altering cardiac function and causing congestive heart failure. Some examples are:
- Increased amounts of red blood cells
- Profound anemia
- Diseases of the brain, kidneys, and hormone producing glands.
- Poorly managed thyroid disease
- Sarcoidosis,amyloidosis, high cholesterol, a family history, smoking, aging, connective tissue disorders, etc. can also increase the risk to congestive heart failure.
Treatment of congestive heart failure includes:
- Treatment of underlying diseases that give rise to cardiac problems.
- Reduction in fluid content in the body via diuretics and lowered salt-intake.
- Medications such as ACE inhibitors, beta blockers, ARBs, etc. to control hypertension and heart rate, increase ejection fraction and cardiac output, and promote efficient pumping of the heart.
- Severe cases of congestive heart failure may need left ventricular assist devices or heart transplantation.
How long can you live with congestive heart failure?
- Controlled congestive heart failure is not a cause of worry and patients may live long normal lives.
- Severe congestive heart failure requiring hospitalization comes with a substantial mortality rate of over 20 percent at one year.
- NYHA stage IV patients have a mortality risk of nearly 50 percent.