A pacemaker is a small electronic device surgically placed in the chest to help manage abnormal heart rhythms, using electrical pulses to prompt the heart to beat at a normal rate. The implantation of any foreign object carries a small risk of infection. A pacemaker infection is a serious, though uncommon, complication that requires prompt medical intervention. Awareness of the signs and the proper treatment protocol is paramount for individuals with these cardiac implantable electronic devices (CIEDs).
Where Pacemaker Infections Occur
Pacemaker infections are categorized based on their anatomical location: localized pocket infections and systemic, or lead-related, infections. The pocket infection is the most common form, developing at the surgical site where the pulse generator rests beneath the skin. This infection is typically localized to the upper chest and often occurs within the first year after implantation. The pathogens, most frequently Staphylococcus species, are usually introduced during the implantation procedure itself.
The second, more serious type is a lead or systemic infection, involving the pacing leads that travel through blood vessels into the heart chambers. This infection often manifests as infective endocarditis, which is the infection and inflammation of the heart lining or valves. The bacteria adhere to the surface of the leads, forming a protective layer called a biofilm that makes the infection extremely difficult to eradicate with antibiotics alone. Systemic infection can arise from an untreated pocket infection that tracks along the leads or from bacteria traveling through the bloodstream from a distant site, known as hematogenous seeding.
The distinction between these two locations is significant because a seemingly minor pocket infection can harbor bacteria that have already contaminated the leads. Studies show that even when symptoms appear strictly localized to the pocket, the intravascular portion of the leads may be infected in a majority of cases. Complete removal of the entire system is often necessary to resolve the infection due to the risk of progression from the pocket to the leads and heart.
Identifying Symptoms of Infection
Symptoms vary depending on whether the infection is localized to the generator pocket or has become systemic. Localized symptoms are often the first observable signs at the incision site. These signs include redness (erythema), swelling, tenderness, and warmth over the implanted device area.
Drainage from the wound may be clear, bloody, or contain pus. A particularly concerning sign is skin erosion, where the pulse generator or leads begin to push through the skin barrier. Any break in the skin over the device is considered an infection of the entire system.
Systemic symptoms, which suggest the infection has spread to the bloodstream or heart, are often less specific and can mimic a common flu or other illness. Persistent fever and chills without another obvious cause are common indicators of a bloodstream infection. Patients may also experience general malaise, fatigue, or unexplained weight loss. If the infection has caused severe endocarditis on the heart valves, signs of heart failure might also develop.
Reducing the Risk of Infection
Minimizing the risk of pacemaker infection involves procedural precautions and careful patient management. A primary step is the use of prophylactic antibiotics, administered intravenously before the incision. This standard practice significantly reduces infection risk by targeting common contaminating bacteria. Meticulous surgical technique, including the use of specialized skin antiseptics such as chlorhexidine-alcohol, also prevents bacteria from entering the wound.
Device replacement or revision procedures carry a risk of infection two to four times higher than a first-time implantation. The presence of a post-operative hematoma (blood collection) at the implant site also increases the chance of subsequent infection. Centers that perform a high volume of implants tend to have lower infection rates.
Several patient-related factors, known as comorbidities, can increase susceptibility to infection. Patients with diabetes mellitus, end-stage kidney disease (especially those on dialysis), heart failure, or those using immunosuppressive drugs are at a higher risk. Optimizing the management of these underlying conditions before the procedure, such as achieving better blood sugar control, can help lower the infection burden.
After the procedure, post-implant care is essential for prevention. Patients must follow instructions for incision care, keeping the site clean and dry. They should avoid trauma to the implant area and monitor the site daily for any new signs of redness or swelling. Seeking immediate medical attention for concerning symptoms is crucial to prevent a localized issue from progressing into a systemic infection.
Treatment for Infected Devices
Once a pacemaker infection is suspected, diagnostic confirmation guides treatment. Doctors use blood cultures to identify the specific pathogen causing the systemic infection. Imaging, such as a transesophageal echocardiogram, visualizes the pacing leads and heart valves to check for vegetations, which indicate infective endocarditis. Samples may also be taken from the pulse generator pocket if localized signs are present.
The standard of care for treating an infected pacemaker involves a combination of antibiotic therapy and complete device removal. Antibiotic therapy is initiated promptly, often using intravenous (IV) antibiotics tailored to target the identified bacteria. However, antibiotics are rarely sufficient on their own because the bacteria form a protective biofilm on the foreign material of the device.
Complete device removal, or extraction, is considered mandatory for most systemic and many localized infections. Since the biofilm shields the bacteria, it is nearly impossible to eradicate the infection without physically removing all foreign material—the pulse generator and all associated leads. The procedure to remove the leads is called transvenous lead extraction, typically performed using specialized tools like laser sheaths or locking stylets to safely detach the leads from the blood vessel walls and heart tissue.
If the patient is pacemaker-dependent, a temporary pacing system is often placed before or during extraction to maintain a stable heart rhythm. Failure to remove the entire system significantly increases the risk of the infection returning. After the infected system is fully removed, the patient undergoes a full course of antibiotics, typically lasting several weeks. A new pacemaker is only implanted after blood cultures are confirmed negative and the patient is clinically stable, often involving a waiting period of at least one to two weeks.