A pacemaker is a small device implanted beneath the skin, typically near the collarbone, that helps regulate the heart’s rhythm using electrical impulses. The pulse generator contains the battery and electronic circuitry. The generator must eventually be replaced because the power source has a finite lifespan. This replacement procedure is a planned, routine surgery that is generally less involved than the original implantation, providing safe and continuous cardiac support.
Monitoring and Timing the Replacement
The generator replacement process is highly scheduled, ensuring the device is exchanged long before the battery fully depletes. Modern pacemakers typically have a battery life ranging from 7 to 15 years. The lifespan depends on how often the device needs to pace the heart; the more active the pacemaker is, the faster the battery is consumed.
Regular follow-up appointments with a cardiac device specialist are essential to monitor the battery’s status. These checks assess the battery voltage, internal resistance, and overall function of the device, often using specialized programmers or remote monitoring systems. Remote monitoring allows the device to transmit data wirelessly to the clinic, making it possible to catch subtle changes in performance from the patient’s home.
A predetermined threshold known as the Elective Replacement Indicator (ERI) signals the need for a planned replacement. Reaching ERI means the battery voltage has dropped, indicating replacement should be scheduled within the next three to six months. Some devices may also enter an energy-conserving mode at ERI, such as switching to a fixed, lower pacing rate, to extend the remaining battery life.
The Generator Replacement Procedure
The generator replacement is a straightforward operation, usually performed as an outpatient procedure or with a single overnight hospital stay. The patient is typically given a local anesthetic to numb the area over the existing pacemaker site. Mild sedation is sometimes provided to help with relaxation.
Before surgery, the patient is connected to monitoring equipment to track vital signs, and antibiotics are administered intravenously to prevent infection. The surgeon makes a small incision, usually directly over the original scar tissue, to access the existing device pocket beneath the skin.
Once the old pulse generator is exposed, the surgeon carefully disconnects the leads, which are the thin, insulated wires extending to the heart muscle. The leads are generally left in place and reused, assuming they are functioning correctly. The old generator is then removed from the pocket.
The existing leads are thoroughly tested to ensure they are still capable of delivering electrical impulses and sensing the heart’s natural rhythm. If the leads pass these tests, the new generator is connected to them and placed into the cleaned pocket. Replacing the leads is a more complex procedure, only done if a lead is damaged or infected.
After connecting the new device, the surgical team tests its function and programs it to the patient’s specific needs. The surgeon then closes the incision using sutures or surgical glue. The entire procedure is typically completed within an hour, and the patient is moved to a recovery area for monitoring before discharge.
Recovery and Long-Term Care
Following the generator change, the patient spends a few hours in a recovery area while the medical team monitors the incision site and the new device’s rhythm. Most patients return home the same day or after an overnight observation period. Mild soreness, swelling, or bruising around the incision site is common and typically subsides within one to two weeks.
Specific recovery instructions are provided to protect the incision and ensure the leads remain securely in place. Patients are advised to avoid lifting the arm on the device side above the shoulder for about a week to prevent the leads from shifting position. Heavy lifting and strenuous activity should also be restricted for one to two weeks as the body heals.
Incision care involves keeping the area clean and dry, with guidance provided on showering and scheduling a wound check appointment about a week later. Routine follow-up appointments are scheduled every 6 to 12 months to monitor the new generator’s function. Patients are also given an updated identification card reflecting the new device information, which should be carried at all times.