Congestive Heart Failure
Revascularization surgery helps to restore blood flow to the heart. It can treat blocked arteries in patients with coronary artery disease and may help select patients with heart failure. Surgery types include coronary artery bypass graft (CABG) and angioplasty (also called percutaneous coronary intervention [PCI]). CABG is a traditional type of open heart surgery. Angioplasty uses a catheter to inflate a balloon inside the artery. A metal stent may also be inserted during an angioplasty procedure. [For more information, see In-Depth Report #03: Coronary artery disease.]
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.
Pacemakers, also called pacers, help regulate the heart’s beating action, especially when the heart beats too slowly. Biventricular pacers (BVPs) are a special type of pacemaker used for patients with heart failure. Because BVPs help the heart’s left and right chambers beat together, this treatment is called cardiac resynchronization therapy (CST).
BVPs are recommended for patients with moderate-to-severe heart failure that is not controlled with medication therapy and who have evidence of left-bundle branch block on their EKG. Left-bundle branch block is a condition in which the electrical impulses in the heart do not follow their normal pattern, causing the heart to pump inefficiently.
Implantable Cardioverter Defibrillators (ICDs)
Patients with enlarged hearts are at risk for having serious cardiac arrhythmias (abnormal heartbeats) that are associated with sudden death. Implantable cardioverter defibrillators (ICDs) can quickly detect life-threatening arrhythmias. The ICD is designed to convert any abnormal heart rhythm back to normal by sending an electrical shock to your heart. This action is called defibrillation. This device can also work as a pacemaker.
In recent years, certain ICD models and biventricular pacemaker-defibrillators have been recalled by the manufacturers because of circuitry flaws. However, doctors stress that the chance of an ICD or pacemaker saving a person’s life far outweigh the possible risks of these devices failing.
Ventricular Assist Devices
Ventricular assist devices are mechanical devices that help improve pumping actions. They are used as a bridge to transplant for patients who are on medications but still have severe symptoms and are awaiting a donor heart. In some cases, they may delay the need for a transplant. Therefore they may be used as short-term (less than 1 week) or longer term support.
Ventricular assist devices include:
- Left ventricular assist devices (LVADs) are used for patients whose heart beat has slowed dangerously to help take over the pumping action of the failing heart. Until recently, these machines required remaining in the hospital. Smaller battery-powered implanted LVAD units are now allowing many patients to leave the hospital while they wait for a transplant.
- Intra-aortic balloon pumps are helpful for temporarily maintaining heart function in patients with left-side failure who are waiting for transplants and for those who develop a sudden and severe deterioration of heart function. The IABP is an implanted thin balloon that is usually inserted into the artery in the leg and threaded up to the aorta leading from the heart. Its pumping action is generating by inflating and deflating the balloon at certain rates.
- Fully implanted miniature artificial pumps that assist the heart are also being tested.
The risks and complications involved with many of these devices include bleeding, blood clots, and right-side heart failure. Infections are a particular hazard.
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. About 2,000 heart transplant operations are performed in the United States each year, but thousands more patients wait on a list for a donor heart.
The most important factor for heart transplant eligibility is overall health. Chronological age is less important. Most heart transplant candidates are between the ages of 50 - 64 years.
While the risks of this procedure are high, the 1-year survival rate is about 88% for men and 77% for women. Five years after a heart transplant, about 73% of men and 67% of women remain alive. 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.
Implantable Artificial Heart
Abiocor is a permanent implantable artificial heart. It is available only for patients who are not eligible for a heart transplant and who are not expected to live more than a month without medical treatment. The device requires a large chest cavity, which means that most women are not eligible for it.