What is heart failure?
Heart failure, also called congestive heart failure, is a condition in which the heart cannot pump enough oxygenated blood to meet the needs of the body's other organs. The heart keeps pumping, but not as efficiently as a healthy heart. Usually, the heart's diminshed capacity to pump reflects a progressive, underlying condition. Nearly 5 million Americans are living with heart failure, and 400,000 to 700,000 new cases are diagnosed each year.
What causes heart failure?
Heart failure may result from any or all of the following:
- Heart valve disease caused by past rheumatic fever or other infections
- High blood pressure (hypertension)
- Active infections of the heart valves and/or heart muscle (for example, endocarditis or myocarditis)
- Previous heart attack(s) (myocardial infarction). Scar tissue from prior damage may interfere with the heart muscle's ability to pump normally.
- Coronary artery disease. Narrowing arteries that supply blood to the heart muscle.
- Cardiomyopathy or another primary disease of the heart muscle
- Congenital heart disease/defects (present at birth)
- Cardiac arrhythmias (irregular heartbeats)
- Chronic lung disease and pulmonary embolism
- Certain medications
- Excessive sodium intake
- Anemia and excessive blood loss
- Complications of diabetes
How does heart failure affect the body?
Heart failure interferes with the kidney's normal function of eliminating excess sodium and waste products from the body. In congestive heart failure, the body retains more fluid, resulting in swelling of the ankles and legs. Fluid also collects in the lungs, which can cause profound shortness of breath.
What are the symptoms of heart failure?
The following are the most common symptoms of heart failure. However, each individual may experience symptoms differently. Symptoms may include:
- Shortness of breath during rest, exercise, or while lying flat
- Weight gain
- Visible swelling of the legs and ankles (due to a buildup of fluid), and, occasionally, swelling of the abdomen
- Fatigue and weakness
- Loss of appetite, nausea, and abdominal pain
- Persistent cough that can cause blood-tinged sputum
The severity of the condition and symptoms depends on how much of the heart's pumping capacity has been compromised.
The symptoms of heart failure may resemble other conditions or medical problems. Always consult your health care provider for a diagnosis.
How is heart failure diagnosed?
In addition to a complete medical history and physical examination, diagnostic procedures for heart failure may include any, or a combination of, the following:
- Chest x-ray. A diagnostic test which uses invisible electromagnetic energy beams to produce images of internal tissues, bones, and organs onto film.
- Echocardiogram (also called echo). A noninvasive test that uses sound waves to evaluate the motion of the heart's chambers and valves. The echo sound waves create an image on the monitor as an ultrasound transducer is passed over the heart.
- Electrocardiogram (ECG or EKG). A test that records the electrical activity of the heart, shows abnormal rhythms (arrhythmias or dysrhythmias), and can sometimes detect heart muscle damage.
- BNP testing. B-type natriuretic peptide (BNP) is a hormone released from the ventricles in response to increased wall tension (stress) that occurs with heart failure. BNP levels rise as wall stress increases. BNP levels are useful in the rapid evaluation of heart failure. In general, the higher the BNP levels, the worse the heart failure.
Treatment for heart failure
Specific treatment for heart failure will be determined by your health care provider based on:
- Your age, overall health, and medical history
- Extent of the disease
- Your tolerance for specific medications, procedures, or therapies
- Expectations for the course of the disease
- Your opinion or preference
The cause of the heart failure will dictate the treatment protocol established. If the heart failure is caused by a valve disorder, then surgery may be performed. If the heart failure is caused by a disease, such as anemia, then the underlying disease will be treated. Although there is no cure for heart failure due to damaged heart muscle, many forms of treatment have been used to treat symptoms very effectively.
The goal of treatment is to improve a person's quality of life by making the appropriate lifestyle changes and implementing drug therapy.
Treatment of heart failure may include:
- Controlling risk factors
- Losing weight (if overweight)
- Restricting salt and fat from the diet
- Stop smoking
- Abstaining from alcohol
- Proper rest
- Controlling blood sugar if diabetic
- Controlling blood pressure
- Limiting fluids
- Medication, such as:
- Angiotensin converting enzyme (ACE) inhibitors. This medication decreases the pressure inside the blood vessels and reduce the resistance against which the heart pumps.
- Angiotensin receptor blockers (ARB). This is alternative medication for reducing workload on the heart if ACE inhibitors are not tolerated.
- Diuretics. These reduce the amount of fluid in the body.
- Vasodilators. These dilate the blood vessels and reduce workload on the heart.
- Digitalis. This medication helps the heart beat stronger with a more regular rhythm.
- Inotropes. These increase the pumping action of the heart muscle.
- Antiarrhythmia medications. These help maintain normal heart rhythm and help prevent sudden cardiac death.
- Beta-blockers. These reduce the heart's tendency to beat faster and reduce workload by blocking specific receptors on heart cells.
- Aldosterone blockers. Medication that blocks the effects of the hormone aldosterone which causes sodium and water retention.
- Biventricular pacing/cardiac resynchronization therapy. A new type of pacemaker that paces both pumping chambers of the heart simultaneously to coordinate contractions and improve the heart's function. Some heart failure patients are candidates for this therapy.
- Implantable cardioverter defibrillator. A device similar to a pacemaker that senses when the heart is beating too fast and delivers an electrical shock to convert the fast rhythm to a normal rhythm.
- Heart transplantation
- Ventricular assist devices (VADs)
Ventricular assist devices (VADs)
A ventricular assist device (VAD) is a mechanical device that is used to take over the pumping function for one or both of the heart’s ventricles, or pumping chambers. A VAD may be necessary when heart failure progresses to the point that medications and other treatments are no longer effective.
For persons with severe or end-stage heart failure, ventricular assist devices (VADs) may be required to support the heart in order to ensure an adequate cardiac output (amount of blood pumped out by the heart per minute) to meet the body’s needs.
Heart transplantation is an option for some patients with severe heart failure (HF), but during this late stage of HF, over 50 percent of persons on a waiting list for heart transplantation will die before receiving a donor heart. Organ donors are in short supply and do not meet the demand for patients waiting for heart transplant. The wait time for heart transplantation varies from days to months.
Long wait times and decreased availability of donors has led doctors and researchers to seek other methods to support the failing heart. Patients may die waiting for a transplant or other important organs such as the liver and kidney may become permanently damaged before a donor heart is available. VADs have shown great promise in maintaining adequate blood circulation in cases of severe HF.
VADs may be used in the following situations:
- Bridge to transplant. The implantation of a VAD to support the patient with end-stage HF who is waiting for heart transplantation.
- Bridge to recovery. The implantation of a VAD to support the patient with potentially reversible HF. Once the heart has recovered sufficiently, the VAD may be removed.
- Destination therapy. The implantation of a VAD to support the patient with end-stage HF who is not a candidate for heart transplantation. A portable VAD may be used in this situation so that the patient may be discharged from the hospital and return home.
The two basic types of VAD's are left ventricular assist (LVAD) which is the most common, or the right ventricular assist (RVAD). If both are used at the same time it is called biventricular assist (BIVAD). However a BIVAD is not a separate type of VAD.
VADs are most commonly implanted during a process similar to other types of open heart surgery.
All types of VADs have similar complications postoperatively and during prolonged therapy:
- Infection. Infection is a serious complication that occurs frequently. Patients in general are vulnerable to postoperative infections such as intravenous (IV) line infections, pneumonia, and urinary tact infections. The patient receiving a VAD is at even greater risk due in part to the patient's weakened state. VAD-related infections may occur at the skin where the device is inserted into the body, in the heart (endocarditis), or in the blood stream (sepsis).
To minimize the risk of infections, all cannula (tubing) exit sites must be dressed daily using sterile technique, the exit cannulas must be secured to prevent tension and pulling on the skin, and the skin around all exit sites must be completely healed before extensive activity is allowed.
- Bleeding. Bleeding is common in the immediate postoperative period due to cardiopulmonary (heart-lung) bypass time, anticoagulation (prevention of blood clotting with medication), and long surgical procedures. Additionally, liver dysfunction (which may be present preoperatively) and previous heart surgeries increase the patient's risk for bleeding. Blood transfusions may be required for major bleeding, but are avoided if possible.
- Right ventricular failure. Right ventricular failure is a concern in patients who have high pressures in the lung circulation before implantation of a VAD. Medications can help support the right ventricle during the initial period of recovery until the device begins to improve the overall cardiac output.
- Thromboembolism (blood clot). Thromboembolism (blood clot) may cause strokes. All VADs increase the risk of clot formation because blood comes in contact with the surfaces of the mechanical pump and cannulas. Almost all VADs require some form of anticlotting medicines to reduce the risk of stroke. These medications may put the patient at greater risk for bleeding, however, and should be closely monitored.
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