Studies suggest that 20 to 30 percent of patients with congestive heart failure have hearts that do not beat in a synchronized fashion.

One treatment option for this condition is to implant an artificial pacemaker – or pacer – to help improve the pumping action. Pacemakers come in a variety of types, each programmed to respond to a particular problem. The biventricular pacer is one of the latest developments available at leading cardiac centers to treat congestive heart failure.

What is a biventricular pacer?
A pacer is a small electrical generator powered by a battery with wires running to the heart. The device is implanted under the skin of the chest to restore synchronous contraction of the heart, and thereby improving symptoms of congestive heart failure. Computer-like circuitry inside the device transforms the energy from the battery into tiny electrical pulses that travel to the heart through special wires called leads. Depending on the problem, these leads may be placed in the atrium, the ventricle, or in both the atrium and ventricle. Electrodes on the tips of these leads touch the heart wall.

The biventricular pacer is one of the newest devices used for patients with congestive heart failure who have problems in both the left and right lower heart chambers. The pacer has shown success in forcing the ventricles to beat in proper relation to each other. Synchronizing the heart’s chambers makes it work more efficiently.

Who should get a biventricular pacer?
If the heart is simply beating weakly, the biventricular pacer will not help. The patients who will benefit the most from this new technology are only those whose heart failure stems from a lack of synchrony in the organ’s functioning.

To determine if you are a good candidate for a biventricular pacer, you will need an electriocardiogram (ECG) which monitors the heart’s electrical activity in each chamber and ventricle. The results of this painless test will determine if you are a good candidate for a pacemaker.

How does the biventricular pacer help?
Pacemakers help the heart to function normally by re-timing the beat of some of the chambers and therefore can improve the efficiency of the heart and prevent associated problems of congestive heart failure.

The pacer is programmed by the physician according to what the patient’s heart requires. Adjustments are made as to the strength and duration of the electronic impulse, how fast it goes, and the pause between stimulating the atrium and ventricle.

Implanting the biventricular pacer in appropriate patients has been shown to reduce symptoms, hospitalization and mortality, compared to other treatments for congestive heart failure. Other benefits include improved exercise tolerability and quality of life in some after receiving the biventricular pacer. Despite the occasional discomfort of pacers, patients typically say the device gives them a sense of security.

How is the pacer implanted?
Inserting the pacer is considered minor surgery in most cases. Usually, sedation is used – not general anesthesia. A local anesthetic is administered to numb the area where the device will be placed. A surgeon makes an incision and a pocket (about 3 inches by 2 inches) is created for the pulse generator.

Guided by X-ray images, the pacemaker leads are introduced into a vein near the site of the pocket and then advanced through the large veins leading to the heart. Once confirmed to be functioning, the leads are attached to the pulse generator. The pulse generator is then secured to the underlying muscle with a suture before the wound is closed.

The resulting scar will be about three inches long. In very thin individuals, the pulse generator may be noticeable underneath the skin. On heavier people, there may be no outward evidence of a pacemaker at all.

What happens after the surgery?
The patient will spend the next night or two in the hospital after the implant. Many will need to wear a sling or “immobilizer” on the arm during that time. The surgical site will probably be uncomfortable for one to two weeks. Analgesics (aspirin, acetamenophen or ibuprofen) can provide relief.

Before leaving the hospital, patients will get an ID card for their wallets containing details about the pacemaker in the event of an emergency. The patient’s activities may be limited the first two weeks after surgery because vigorous motion of the affected arm and hand could cause the leads of the new pacemaker to move or be dislodged.

In four to eight weeks after the procedure, the surgeon will re-program the pacemaker to make sure it is working properly.

Are there risks associated with this procedure?
Bleeding, blood clots, infection or a punctured lung are among the possible risks of pacer implantation. The devices could also malfunction. These problems are not common, but patients with pacers should call their physicians if they experience any of these signs:

• Pain at the pacer site
• Swelling of the arm or hand where the pacemaker was placed
• Shortness of breath
• Signs of infection: redness, heat, oozing
• Reappearance of congestive heart failure symptoms that had initially disappeared

How do I know if the pacemaker is working?
Pacemakers are designed so they can provide certain information to the patient instantly through “transtelephonic follow-up.” When a special phone device is placed over the pacemaker, it sends out sounds that can be carried over telephone wires and read by electrocardiographic tracing. This maintenance check should be done once a year or as instructed by your physician. Regular follow-up allows you to see when the pacer battery is near depletion.

Pacer batteries generally last from six to 10 years and give indications when they need replacement through an installed magnet. Some pacers also start beeping when the battery gets low. At that point, another surgical procedure is necessary to insert a new battery in the pocket and remove the old one.

Are there restrictions on living with a pacemaker?
A few precautions are necessary to protect the pacemaker. For instance, some technology – such as hospital equipment for magnetic resonance imaging – can create a high-energy field that will re-program pacemakers accidentally. Cellular telephones, particularly the digital variety, can cause interference problems as well. Your physician will provide instructions about any particular hazards.

Advanced circuitry, however, has improved the new pacemakers so you should not have to avoid airport security detectors, radar or microwave ovens.

For an appointment with a Jefferson physician, more information or health information and education programs, please call 1-800-JEFF-NOW (1-800-533-3669) or hearing-impaired callers can access JEFF NOW® by calling 1-800-654-5984.