Cardiac device infections

Cardiac device infections refers to the infection of implanted electronic devices such as pacemakers, implantable cardiac defibrillators and even left ventricular assist devices. 

Infections can be superficial or deep.  Superficial infections often occur near the skin surfaces. For deep infections, the leads / hardware implanted within the heart tissue  / heart tissue itself (e.g. heart valves) are infected.

Common symptoms include that of pain, swelling, redness or discharge of pus from implant site. These can be accompanied with fever, chills and rigors.  

Apart from the above mentioned symptoms, in the setting of severe infection, the heart function may be affected. As a result, one may experience signs and symptoms of heart failure (e.g chest pain / tightness, shortness of breath, swelling of ankles). Persistently low blood pressure may be a sign of severe infection. If any of the above mentioned signs and symptoms develop, please present for immediate medical review. 

Implantable cardiac device infections are often associated caused by bacteria found on the skin surfaces. 

Patients with the following medical conditions such as diabetes mellitus, end-stage renal failure, chronic obstructive lung disease, skin disorders, steroid use and use of anti-coagulant drugs are at higher risk of cardiac device infections. 

The risk of cardiac device infection is also increased if:

During the medical consult, the history taken will often give the physician important cluse and raise the clinical suspicion for cardiac device infection. When cardiac device infection is suspected, specialized investigations and imaging techniques can be ordered to help clinch the diagnosis. 

Blood tests are performed to look for signs of infection and to check for bloodstream infections.  Specialised imaging techniques (e.g. ultrasound, computed tomography scan or positive emission (PET-CT))  may sometimes be useful to help physicians evaluate the extent of infection present. Debridement procedures may be subsequently recommended for diagnostic and therapeutic purposes. Infected tissue / device will be sent to the microbiological lab for cultures.

A multidisciplinary approach involving the infectious diseases physicians,  cardiologist and/or cardiothoracic surgeons is important in managing cardiac device infections.

Debridement of the infected tissue or device in combination with antibiotic therapy is the mainstay of therapy.  

Deep seated infections require a long course of intravenous therapy. If the implant cannot be removed, oral antibiotics are often given indefinitely after the course of intravenous therapy to prevent the infection from recurring.