Congestive Heart Failure

Description

Alternative Names

Surgery

Coronary Bypass or Angioplasty. Patients with heart failure and severe coronary artery disease often benefit from angioplasty or bypass surgery. The surgery may enhance the hearts pumping action and help to relieve symptoms.

Click the icon to see an illustrated series detailing coronary artery balloon angioplasty.

Click the icon to see an illustrated series detailing heart bypass surgery.

Mitral Valve Surgery. In appropriate patients, mitral valve surgery may significantly reduce the severity of heart failure. In a study of 92 patients with late-stage heart failure and faulty valves, reconstruction of the hearts mitral valve drastically improved heart function.

CPAP for Treating Sleep Apnea. Heart failure is associated with sleep apnea, in which tissues at the back of the throat periodically collapse and become blocked, causing the sleeper to gasp for air. Sleep apnea has been associated with poorer survival in patients with congestive heart failure. A mask-like device worn over the nose at night that provides continuous positive airway pressure (CPAP) is an effective treatment for sleep apnea. Patients with heart failure who respond to it may experience improvements in ejection fraction and disturbed heart rhythms. There is some question, however, whether it provides long-term benefits for heart failure. Some experts suggest oxygen therapy or the asthma drug theophylline for this condition.

Click the icon to see an image of CPAP treatment.

Devices to Control Heart Arrhythmias and Pumping Actions

A growing array of heart devices and machines are changing the face of heart failure treatment. They have gained widespread acceptance for use as a bridge to transplant in patients who are on medications but still have severe symptoms and are awaiting a donor heart. Increasingly, though, doctors are exploring the possibility that such devices may be satisfactory treatments themselves, forestalling the need for a transplant altogether in some patients.

Ventricular Assist Devices (VADs). Ventricular assist devices are machines that help improve pumping actions. Several models with slightly different features are in use or under investigation. Some include the following:

• Biventricular pacers (BVPs) affect both left and right chambers. They may be beneficial for a large minority of heart failure patients who have left bundle branch block, a condition in which the electrical impulses in the heart do not follow their normal pattern. The InSync pacing system is the first of these devices to be approved specifically to relieve the symptoms of moderate to severe heart failure. It consists of a small pulse generator implanted under the skin near the shoulder and three wires that are threaded to both heart pumps (ventricles). Studies are reporting that the biventricular pacer is improving symptoms and reducing hospitalizations. Additional studies are under way to determine if there is any survival advantage with this procedure. Not all patients benefit, even those who meet the criteria.
• Left ventricular assist device (LVAD) are used for patients whose heartbeat has slowed dangerously (a condition called bradycardia) to help take over the pumping action of the failing heart. Studies now suggest that in some people the use of an LVAD may allow some of the damaged heart muscle to heal, perhaps even helping some patients avoid heart transplants. Until recently, these machines required remaining in the hospital. Smaller battery-powered LVAD units, however, are allowing many patients to leave the hospital and are proving to be effective bridges to heart transplants in adults. The HeartMate, for example, a portable LVADs about the size of a portable CD player (2 in. by 4 in.), is implanted in the upper abdomen. The implanted device plugs into an external power base, which is employed when the patient is at rest to recharge the battery and provide continuous power.
• Fully implanted miniature artificial pumps that assist the heart (not replace it) are also being tested. The DeBakey ventricular assist device (VAD) for example, is a tiny heart pump that weighs less than four ounces. It has been approved in Europe. The Jarvik 2000 heart pump is also showing promise.

There are risks involved with many of these devices, including bleeding, blood clots, and right-side heart failure. Infections are a particular hazard.

Intra-aortic Balloon Pump.The intra-aortic balloon pump (IABP) is helpful for maintaining heart function in people with left-side failure waiting for transplants and in those who develop a sudden and severe deterioration of heart function.

• The IABP is an implanted thin balloon usually inserted into the artery in the leg and threaded up to the aorta leading from the heart.
• Its pumping action is generated by inflating and deflating the balloon at certain rates.

Usually, it is used only for short periods, but some studies indicate that patients may be able to use it safely for somewhat longer periods (an average duration of 23 days in one study).

Implantable Cardioverter-Defibrillators. Devices called Implantable cardioverter-defibrillators (ICDs), which are sometimes combined with pacemakers, may be effective for preventing arrhythmias in heart failure patients. Studies have found them effective in preventing sudden death from severe rhythm disturbances in patients with weakened hearts from previous arrhythmias and in patients with genetic hypertrophic cardiomyopathy. They have also shown limited benefits in improving exercise capacity and quality of life and slowing the progression of heart failure.

Ventricular Remodeling and Restoration

Ventricular Remodeling. Ventricular remodeling (also called partial left ventriculectomy or the Batista procedure, after its inventor) may allow some patients with dilated cardiomyopathy to avoid a heart transplant.

The procedure involves the following:

• The surgeon first performs ventriculectomy, which is the removal of a section of healthy heart muscle weighing about three ounces.
• The surgeon then reshapes the heart to a more normal size and form.
• Any faulty heart valves are repaired.

Ventricular remodeling is still relatively new and mortality rates are very high. More research is needed to target the patients who would most benefit. Studies on long-term improvement are mixed to date.

Surgical Anterior Ventricular Endocardial Restoration (SAVER). A related operation called surgical anterior ventricular endocardial restoration (SAVER), or the Dor procedure (after its inventor), combines elements of ventricular remodeling and coronary bypass surgery. It may be beneficial for those whose heart muscle has been scarred by a heart attack. An early study found that 85% of patients who had the surgery did not need to return to the hospital during an 18-month follow-up period. Additional trials are under way.

Dynamic Cardiomyoplasty

Dynamic cardiomyoplasty is an investigative treatment that has been useful in carefully selected patients with congestive heart failure, though long-term and larger studies are still needed:

• The procedure detaches one end of a muscle from the back and wraps it around the ventricles of the heart.
• After a few weeks, these relocated muscles are conditioned with a pacemaker to behave and beat as if they were heart muscles.

Initial tests indicated that the procedure benefited the failing heart in many ways, including improving systolic pressure, limiting dilation of the heart, reducing heart muscle stress, and possibly reversing unwanted cardiac remodeling. But there have been subsequent problems with heart rhythm disturbances and in conditioning the relocated muscles, and one study was stopped because of no difference in survival rates in patients with or without this procedure. Additional experience indicated that it was the restraining effect of the muscle wrap on the weakened heart that may have provided key benefits. Surgeons, then, are now investigating cardiac support devices that cradle the heart in a mesh-like support as a possible new surgical avenue.

Implantable Artificial Heart

Surgeons implanted the first self-contained, artificial heart, known as the AbioCor, in five Americans in 2001. The heart, powered by an external battery that transmits electrical pulses through the skin, is a yo-yo shaped device about the size of a grapefruit. Although it did extend survival somewhat during these initial tests, it is highly experimental and intended only for those with very severe heart damage who are not expected to live longer than 30 days.

Heart Transplantation

Patients who suffer from severe heart failure and whose symptoms do not improve with drug therapy or mechanical assistance may be candidates for heart transplantation. Some 3,700 people are awaiting a transplant, although only about 2000 operations are performed each year. Not all transplant units accept Medicare patients.

Traditionally transplants are performed only on more robust patients and patients under 60. About 76% of transplant patients are male and 85.4% are white. Studies now suggest that older and sicker patients may achieve the best benefits. In fact, a study of almost 900 patients found that transplantation increased survival only for the sickest of patients.

While the risks of this procedure are high, the two-year survival rate is about 78% and after five years it ranges from 50% to over 70%. In general, the highest risk factors for death three or more years after a transplant operation are coronary artery disease and the adverse effects (infection and certain cancers) of immunosuppressive drugs used in the procedure. The rejection rates in older people appear to be similar to those of younger patients.