Congestive Heart Failure
Congestive heart failure (CHF), congestive cardiac failure (CCF) or just heart failure, is a condition that can result from any structural or functional cardiac disorder that impairs the ability of the heart to fill with or pump a sufficient amount of blood through the body.
Because not all patients have volume overload at the time of initial or subsequent evaluation, the term "heart failure" is typically a more preferred term.
Heart failure should not to be confused with "cessation of heartbeat", which is known as asystole, or with cardiac arrest, which is the cessation of normal cardiac function with subsequent hemodynamic collapse leading to death.
Heart Failure is a Chronic Disease
Heart failure is usually a chronic disease. That means it's a long-term condition that tends to gradually become worse. By the time someone is diagnosed, chances are that the heart has been losing pumping capacity little by little for quite a while.
How it Occurs
Heart failure has many causes and can evolve in different ways:
- It can be a direct, last-stage result of heart damage from one or more of several heart or circulation diseases.
- It can occur over time as the heart tries to compensate for abnormalities caused by these conditions, a condition called remodeling.
In all cases, the weaker pumping action of the heart means that less blood is sent to the kidneys. The kidneys respond by retaining water and salt. This in turn increases edema (fluid buildup) in the body, which causes widespread damage.
High Blood Pressure
Uncontrolled high blood pressure, or hypertension, can cause a heart attack, but it is also a major cause of heart failure even in the absence of an attack. In fact, about 75% of cases of heart failure start with hypertension. It generally develops in the following way:
- To compensate for increased blood pressure, the heart muscles thicken.
- Over time the force of the heart muscle contractions weakens and the muscles have difficulty relaxing, thereby preventing the normal filling of the heart with blood.
- Eventually the heart and body just can't keep up, and the person experiences the fatigue, breathing problems or other symptoms that usually prompt a trip to the doctor.
These temporary measures mask the problem of heart failure, but they don't solve it. This helps explain why some people may not become aware of their condition until years after their heart begins its decline. Because of these masking activities it is very important to have a regular checkup with your doctor.
Coronary Artery Disease
Coronary artery disease is the end result of a complex process called atherosclerosis. It is the most common cause of heart attack and involves the build-up of unhealthy cholesterol on the arteries, with inflammation and injury in the cells of the blood vessels. The arteries narrow and become brittle and subject to damage. Heart failure in such cases most often results from a localized pumping defect in the left side of the heart (see below for more on left heart failure).
Damage from a Previous Heart Attack
Heart failure can also occur later in life from the physical damage done to the heart muscles by ta previous heart attack.
Valvular Heart Disease
The valves of the heart control the flow of blood leaving and entering the heart. Abnormalities can lead to heart failure in the following ways:
Types of Heart Failure
- The valves can narrow, causing a backup of blood.
- The valves can close improperly, causing blood to leak back into the heart.
Heart failure can involve the heart's left side, right side or both sides. However, it usually affects the left side first.
- Left-sided or left ventricular (LV) heart failure involves the heart's left ventricle (lower chamber). Oxygen-rich blood travels from the lungs to the left atrium, then on to the left ventricle, which pumps it to the rest of the body. Because this chamber supplies most of the heart's pumping power, it's larger than the others and essential for normal function.
- If the left ventricle loses its ability to contract normally (called systolic failure), the heart can't pump with enough force to push enough blood into circulation. If the ventricle loses its ability to relax normally (diastolic failure) because the muscle has become stiff, the heart can't properly fill with blood during the resting period between each beat. This is an important distinction because the drug treatments for each type of failure are different. In either case, blood coming into the left chamber from the lungs may "back up," causing fluid to leak into the lungs. (The technical term for this ispulmonary edema.) Also, as the heart's ability to pump decreases, blood flow slows down, causing fluid to build up in tissues throughout the body (edema). This excess fluid or congestion explains the term congestive heart failure, which you've probably heard before.
Right-sided or right ventricular (RV) heart failure usually occurs as a result of left-sided failure.
- When the left ventricle fails, increased fluid pressure is, in effect, transferred back through the lungs, ultimately damaging the heart's right side.
- When the right side loses pumping power, blood backs up in the body's veins. This usually causes swelling in the legs and ankles.
- Shortness of breath not related to exercise or exertion
- Increases in swelling of the lower limbs (legs or ankles)
- Sudden weight gain (three or more pounds in one day, five or more pounds in one week (It is very important for people with heart failure to weigh themselves every day — preferably every morning, before breakfast and after urinating, with the same type of clothes on, without shoes, on the same scale and in the same spot)
- Swelling or pain in the abdomen
- Trouble sleeping (waking up short of breath, using more pillows)
- Frequent dry, hacking cough
- Increased fatigue
If caught early, these symptoms may just require an adjustment in medication, as opposed to being life threatening.
A single risk factor may be enough to cause heart failure, but a combination of factors increases your risk. Risk factors include:
- High blood pressure. Your heart works harder than it has to if your blood pressure is high.
- Coronary artery disease. Narrowed arteries may limit your heart's supply of oxygen-rich blood, resulting in weakened heart muscle.
- Heart attack. Damage to your heart muscle from a heart attack may mean your heart can no longer pump as well as it should.
- Irregular heartbeats. These abnormal rhythms can create extra work for your heart, weakening the heart muscle.
- Viruses. A viral infection may have damaged your heart muscle.
- Alcohol use. Alcohol can weaken heart muscle and lead to heart failure.
- Kidney conditions . These can contribute to heart failure because many can lead to high blood pressure and fluid retention.
- Diabetes. Diabetes increases your risk of high blood pressure and coronary artery disease.
- Some diabetes medications. The diabetes drugs rosiglitazone (Avandia) and pioglitazone (Actos) have been found to increase the risk of heart failure. Don't stop taking these medications on your own, though. If you're taking them, discuss with your doctor whether you need to make any changes.
- Sleep apnea. The inability to breathe properly at night results in low blood oxygen levels and increased risk of abnormal heart rhythms. Both of these problems can weaken the heart.
- Congenital heart defects. Some people who develop heart failure were born with structural heart defects.
To diagnose heart failure, your doctor will take a careful medical history and perform a physical , and will also check for the presence of risk factors such as high blood pressure. After the physical exam, your doctor may do a series of tests such as:
- Blood test. Your doctor may take a sample of your blood to check your kidney and thyroid function and to look for indicators of other diseases that affect the heart. In addition, your doctor may check your blood for specific chemical markers of heart failure, such as a hormone called brain natriuretic peptide (BNP). Although first identified in the brain, BNP is secreted by the heart at high levels when it's injured or overworked.
- Chest X-ray. X-ray images help your doctor see the condition of your lungs and heart. In heart failure, your heart may appear enlarged and fluid buildup may be visible in your lungs. Your doctor can also use an X-ray to diagnose conditions other than heart failure that may explain your signs and symptoms.
- Echocardiogram. An important test for diagnosing and monitoring heart failure is the echocardiogram. An echocardiogram also helps distinguish systolic heart failure from diastolic heart failure, in which the heart is stiff and can't fill properly. An echocardiogram uses sound waves to produce a video image of your heart. This image can help doctors determine how well your heart is pumping by measuring the percentage of blood pumped out of your heart's main pumping chamber (the left ventricle) with each heartbeat. This measurement is called the ejection fraction.
- Electrocardiogram (ECG). This test records the electrical activity of your heart through electrodes attached to your skin. Impulses are recorded as waves and displayed on a monitor or printed on paper. An ECG can help identify heart rhythm problems and damage to your heart from a heart attack that may be underlying heart failure.
- Ecocardiogram. Your ejection fraction is an important measurement of how well your heart is pumping and is used to help classify heart failure and guide treatment. In a healthy heart, the ejection fraction is about 60 percent — meaning 60 percent of the blood that fills the ventricle is pumped out with each beat.
- Cardiac CT or MRI scan. These tests are now being used with increased frequency for people with heart failure, not only to measure ejection fraction but to check the heart arteries and valves, determine if you have had a heart attack, and look for unusual causes of heart failure.
- Coronary catheterization (angiogram). In this test, a thin, flexible tube (catheter) is inserted into a blood vessel at your groin or arm and guided through the aorta into your coronary arteries. A dye injected through the catheter makes the arteries supplying your heart visible on an X-ray. This test helps doctors identify narrowed arteries to your heart (coronary artery disease) that can be a cause of heart failure. The test may include a ventriculogram — a procedure to determine the strength of the left ventricle (the heart's main pumping chamber) and the health of the heart valves.
- Stress test. You may have one of a variety of stress tests either using an exercise bike or treadmill or medications that stress the heart.
Classifyications of Heart Failure
To determine the best course of treatment, doctors may classify heart failure using two scales:
- American College of Cardiology scale. This newer classification system uses letters A to D. The system includes a category for people who are at risk of developing heart failure. For example, a person who has several risk factors for heart failure is Stage A, but a person with end-stage heart failure requiring hospice care is Stage D. Doctors use this classification system to identify your risk factors and begin early, more aggressive treatment to help prevent or delay heart failure.
- New York Heart Association scale. This scale classifies heart failure in categories from one to four. In Class I heart failure, the mildest form, you can perform everyday activities and not feel winded or fatigued. Class IV is the most severe, and you're short of breath even at rest.
Ask your doctor about your score if you're interested in determining the severity of your heart failure. Your doctor can help you interpret your score and plan your treatment based on your condition.
Heart failure is a chronic disease needing lifelong management. However, with treatment, a failing heart can become stronger and signs and symptoms of heart failure can improve.
For most people, treatment will include a combination of medication, lifestyle changes and sometimes devices that help the heart beat properly.
Doctors usually treat heart failure with a combination of medications; depending on your symptoms. Available medicines include:
- Angiotensin-converting enzyme (ACE) inhibitors. ACE inhibitors are a type of vasodilator, a drug that widens or dilates blood vessels to lower blood pressure, improve blood flow and decrease the workload on the heart. Examples include enalapril (Vasotec), lisinopril (Prinivil, Zestril) and captopril (Capoten). ACE inhibitors also blunt some of the effects of hormones that promote salt and water retention. ACE inhibitors help people with heart failure live longer and feel better.
- Diuretics. Often called water pills, diuretics make you urinate more frequently and keep fluid from collecting in your body.The drugs also decrease fluid in your lungs, so you can breathe more easily. Commonly prescribed diuretics for heart failure include bumetanide (Bumex) and furosemide (Lasix). Because diuretics make your body lose potassium and magnesium, your doctor may also prescribe supplements of these minerals. If you're taking a diuretic, your doctor will likely monitor levels of potassium and magnesium in your blood through regular blood tests.
- Aldosterone antagonists. These drugs include spironolactone (Aldactone) and eplerenone (Inspra). They're primarily potassium-sparing diuretics, but they have additional properties that help the heart work better, may reverse scarring of the heart and may help people with severe heart failure live longer. Unlike some other diuretics, spironolactone can raise the level of potassium in your blood to dangerous levels.
- Angiotensin II (A-II) receptor blockers (ARBs). These drugs, which include losartan (Cozaar) and valsartan (Diovan), have many of the beneficial effects of ACE inhibitors, but they don't cause a persistent cough, like ACE inhibitors may do. They may be an alternative for people who can't tolerate ACE inhibitors.
- Beta blockers. This class of drug slows your heart rate and reduces blood pressure. Examples include carvedilol (Coreg), metoprolol (Lopressor) and bisoprolol (Zebeta). These medicines also reduce the risk of some abnormal heart rhythms. Beta blockers may reduce signs and symptoms of heart failure and improve heart function.
- BiDil. BiDil is a medication that combines hydralazine and isosorbide dinitrate — both of which dilate and relax the blood vessels. BiDil increases survival when added to standard therapy in black people with advanced heart failure. This is the first drug studied and approved for a specific racial group. Further studies will be necessary to determine if this combination medicine will be helpful for others with heart failure.
- Digoxin (Lanoxin). This drug, also referred to as digitalis, increases the strength of your heart muscle contractions. It also tends to slow the heartbeat. Digoxin reduces heart failure symptoms and improves your ability to live with the condition.
Your doctor may prescribe other heart medications as well — such as:
- nitrates for chest pain,
- a statin to lower cholesterol or
- blood-thinning medications to help prevent blood clots - along with heart failure medications.
Surgery and Medical Devices
In some cases, doctors recommend surgery to treat the underlying problem that led to heart failure. For example, a damaged heart valve may be repaired or, if necessary, replaced with a new one.
Doctors recommend coronary bypass surgery to treat severely narrowed coronary arteries that are contributing to heart failure.
Between 30% to 47% of patients who require hospitalization for heart failure are back in the hospital again within six months. Many people return because of lifestyle factors, such as poor diet, failure to comply with medications, and social isolation. Therefore to be as healthy as you can it is important to:
- Take your prescribed medication.
- Reduce stress. Stress reduction techniques may have direct physical benefits lowering stress hormones, including cortisol (which suppresses the immune system) and norepinephrine (also known as adrenaline), the chemical messenger associated with heart dysfunction.
- Sleep well.
- Eat well. There is some evidence suggesting that the Mediterranean diet helps protect the heart and may even reduce the risk for heart failure after a first heart attack. Its emphasis on whole grains, fish, olive oil, garlic, and moderate, daily intake of wine may have many benefits for the heart. A diet known as Dietary Approaches to Stop Hypertension (DASH) is now recommended as an important step in managing blood pressure so it may be useful for many patients with heart failure. This diet is not only rich in important nutrients and fiber, but also includes foods that contain two and half times the amounts of electrolytes, potassium, calcium, and magnesium as are found in the average American diet.
- Exercise. Many people with heart failure think exercise will hurt them. Studies have shown that moderate physical activity can actually help the heart get stronger. Studies have reported that patients with stable conditions who engage in regular moderate exercise (twice a week) experience a better quality of life and lower mortality rates than those who don't. With daily exercise, most people will find that they don’t feel as tired, they have less stress and their energy level increases. Other advantages include weight control or weight loss, better circulation, and lower blood pressure and cholesterol levels. How much exercise you can do will depend on your specific condition. But even a small amount can improve the way you feel and help you have a more positive attitude. If you can enjoy some recreation, family outings or other leisure activities, you’ll get more pleasure out of life. Before starting any exercise program it is important to be cleared by your physician to do so.