II. Epidemiology
- Device infections increased nearly 4 fold since 1990 as of 2006- Implants on older patients with comorbidities with more frequent revisions
 
- Nearly 31,000 device infections per year in United States- Nearly two thirds are under-treated without device extraction, with a higher mortality and endocarditis risk (see below)
 
- Risk of infection based on device status- Replacement device infection rate: 3%
- New device implant infection rate: 1%
- Existing device, late infection rate: 0.8%
 
III. Precautions
- Pacemakers must be removed for either early or late infections
- Do not aspirate or incise and drain the pocket
- Assume endocarditis (associated with high mortality) in febrile Pacemaker patients
- Pocket infections have mortality rate as high as 20%
- Biofilm infections are more common and with higher rates of Antibiotic Resistance
IV. Risk Factors: Occult Implant Infection as source of Staphylococcus Aureus Bacteremia
- Relapsing bacteremia after appropriate Antibiotics
- No identified source for bacteremia
- Bacteremia persists >24 hours
- ICD Implant
- Prosthetic Cardiac Valve present
- Bacteremia within 3 months of device placement
- (2010) PACE 33(4): 407-13 [PubMed]
V. Pathophysiology: Organisms
- Staphylococcus Aureus (most common)
- Other Gram Positive infections- Coagulase negative Staphylococcus
- Enterococcus species
- Assorted Streptococcus species (Beta hemolytic strep, Pneumococcus, Strep viridans)
 
- 
                          Gram Negative Bacteria
                          - E. coli (45%)
- Klebsiella (20%)
- Pseudomonas (16%)
 
- References
VI. Types
- Early infection- Presents with localized erythema, swelling, purulent discharge within weeks of Pacemaker placement
- Infections occur more often in Diabetes Mellitus, post-placement Hematoma or with Defibrillator placement
 
- Late infection- Most infections occur with one year of implantation- Typically Staphylococcus infections (50% MRSA)
- Gram Negative Bacteria and Fungal Infections are less common
 
- Presents with insidious, slowly developing infection; may only demonstrate an overlying Skin Erosion
- Infections occur more often after Pacemaker manipulations (with 1-3% risk with each manipulation)
- Endocarditis should be assumed (Blood Cultures are positive in 70% of cases, see below)
 
- Most infections occur with one year of implantation
VII. Evaluation
- Palpate the Pacemaker pocket for tenderness, fluctuance suggestive of infection
- Bedside Ultrasound can detect Pacemaker pocker fluid collection
VIII. Labs
- Obtain Blood Cultures (3 sets)
IX. Diagnostics
- 
                          Echocardiogram
                          - Evaluate for valvular vegetation
 
- PET Scan- Can highlight pocket infections
 
X. Management
- Consult cardiology, infectious disease and surgery- Device removal recommended in all cases
- Diagnosis may be unclear in early cases (pocket Hematoma or inflammation versus infection)- Some may opt for early empiric doxycyline course under close interval observation
- Device removal if recurrent symptoms or signs after Antibiotic course
 
- Conservative management of infection (without immediate device removal) is associated with increased mortality- Thirty day mortality is increased 7 fold over early device removal
- One year mortality is increased 3 fold over early device removal
- (2011) Heart Rhythm 8:1678-85 [PubMed]
 
 
- Start empiric Antibiotics after Blood Cultures (adult dosing shown)- Antibiotic course- Pocket infection: 10-14 days
- Lead associated endocarditis: 4-6 weeks (organism specific recommendations exist)
 
- MRSA- Vancomycin 15-20 mg/kg IV q8-12 hours (or Daptomycin 8-10 mg/kg q24 h) AND
- Rifampin 300 mg orally twice daily
 
- MSSA
- References- (2016) Sanford Guide, accessed 3/7/2016
 
 
- Antibiotic course
XI. Prevention
- Prophylactic Antibiotics are not currently recommended at the time of device implantation
XII. References
- (2018) Cardiac Arrhythmia Conference, UMN, Minneapolis
- Jones and Orman in Majoewsky (2012) EM:Rap 12(5): 4-6
- Mallemat, Swaminathan and Egan in Herbert (2014) EM:Rap 14(10): 5-7
- Vanlandingham (2015) Crit Dec Emerg Med 29(10): 2-14
