Practice Update: Cardiology

MY APPROACH 21

My approach to the patient with an infected ICD

By Anne B Curtis MD, FACC, FHRS, MACP, FAHA

Dr Curtis, Charles and Mary Bauer Professor of Medicine and Chair of the Department of Medicine at the University at Buffalo New York, shares her initial evaluation and management of patients with infection of an implantable cardioverter defibrillator.

Initial evaluation andmanagement Infection of an implantable cardioverter defibrillator (ICD) may be suspected if the patient has erythema, pain, swelling, or discharge from the ICD pocket, or signs of systemic infection such as fever or an elevated white blood cell count. Erosion of the skin with visible hard- ware by definition means the device is infected. Risk factors for infection include early reoperation (for exam- ple, because of lead dislodgment), hematoma, generator replacement, upgrade procedures, cardiac resynchro- nization therapy (CRT) procedures, and comorbidities such as diabetes mellitus and chronic kidney disease. In some cases, a stitch abscess or minimal redness of the suture line can be treated conservatively with oral antibiot- ics with complete resolution. One should NEVER open the pocket to flush out infection with the expectation that cure will ensue, nor should one puncture the pocket to obtain a culture. On the other hand, it is important to obtain blood and wound cultures. Transesophageal echocardiography may be helpful in making the diagnosis, but it won’t nec- essarily allow differentiation of thrombus from infected vegetations. Infections aremost commonly due to Staphy- lococcus species. Consultation with an infectious disease specialist is advisable for choice and duration of antibiotic therapy. Duration can range from 10 to 14 days for pocket infection and up to 4 to 6 weeks for endocarditis. Most pocket infections and all cases with positive blood cultures require removal of all hardware, leads, and the generator. Leads are usually easy to remove with sim- ple traction for any recently implanted ICD. When an ICD has been in place for over 6 months, removal of the leads becomes progressively more difficult. These pro- cedures should be performed by physicians skilled in lead extraction. Lead extraction is more complicated in patients who become infected after a generator change, given the length of time the leads have been in place. With CRT defibrillator (CRT-D) therapy, the coronary sinus lead may present additional challenges unless it is a recently implanted passive fixation lead. A critical point is that one should NOT simply cut the leads in the pocket and remove the generator. Such an approach is highly unlikely to cure the infection and will make the task of removing the remainder of the leads more technically difficult.

Infections are most commonly due to Staphylococcus species.

A critical point is that one should NOT simply cut the leads in the pocket and remove the generator. Such an approach is highly unlikely to cure the infection and will make the task of removing the remainder of the leads more technically difficult.

Management of the patient during treatment of the infection In a patient who has had an ICD removed for infection, one should wait until the infection has cleared and the antibiotic course is completed before implanting a new device, usually on the contralateral side. If antibiotics are needed for several weeks and outpatient administration can be arranged, the patient will need protection against sudden cardiac death in the interim. This scenario is one of the best uses for a wearable defibrillator. This approach works well for patients who are not pacemak- er-dependent. Removal of an infected subcutaneous ICD can be handled in a similar way. For patients who have had an ICD removed and who are pacemaker-dependent, management is more complicated. Either the patient will need to stay in the hospital with a transvenous temporary pacemaker until a new ICD is implanted, or a permanent, active-fixation ventricular lead may be implanted that is exteriorized and attached to a pacemaker pulse generator. Such an approach allows the patient more mobility and also permits care at home while the infection clears. The transvenous lead is removed at the time a new ICD sys- tem is implanted. If the reason for pacing is CRT and the patient is not pacemaker-dependent, I would abandon pacing until a new CRT-D system can be implanted.

VOL. 2 • NO. 1 • 2017