cardiac implantable electronic device infections

Implantable Cardiac Electronic Device Infection

Implantable Cardiac Electronic Device

InfectionDr Harish OrugantiNIMS,Hyderabad.


Epidemiology• The overall incidence of ICED infections ranged from 0.5% to 2.2% of patients in 18 studies with

follow-up or study periods between 6 weeks and 11 years

• Incidence was measured in different ways in different studies:1.82 /1000 PPM years foll 10 PPM Denmark registry

1.9 /1000 device years Minnesota study

3.1 /1000 pt years Global study of ICD

10 /1000 pt years CRTD study from Italy (n=3253)

harish oruganti


Epidemiology• incidence of infection with primary implantation is 2- to 5-fold lower than for revision • (primary 0.5%–0.8%, revision 1%–4%) over follow-up periods of between 1 and 3 years)

• REPLACE study (which only included patients undergoing a revision or upgrade of a PM or ICD found that 1.4% of patients suffered an infection over 6 months of follow-up

1 0 PROCEDURE REVISION PROCEDURE

PPM 1.82 5.32 per 1000 pt yrs

CRTD 9 18 per 1000 pt yrs


Epidemiology• Increased rate of infection likely

due to:• Older patients receiving devices• More patient comorbidities• Longer procedures• Increasing number of pulse generator

replacements and upgrades• Revisions• More resistant S aureus and coagulase (-)

Staphylococcus species(e.g., S epidermidis)Greenspon et al. JACC Vol. 58, No. 10, 2011Infection Trends for Pacemakers and ICDs August 30, 2011:1001–6


Epidemiology

• Sohail MR et al. Arch Intern Med. 2011;171(20):1821-1828.


Risk Factors for ICED Infection

Male sex Younger ageAnticoagulation COPD

Renal impairment Lack of antimicrobial prophylaxisType of device Need for re-intervention pror to dischargeHigher number of prior procedures Shorter time from implantation(<1 yr)earlier year of implantation (before 1985) fever in the 24 h prior to implantationuse of a temporary pacemaker prior to implantation congestive heart failureAzotaemia chronic corticosteroid therapyHaemodialysis procedure time/complexitypost-operative haematoma Diabetes(hyperglycemia)

Johansen JB Jorgensen OD Moller Met al. Infection after pacemaker implantation: infection rates and risk factors associated with infection in a population-based cohort study of 46299 consecutive patients Eur Heart J 2011


microbiology• Pathogens were identified in the vast majority

of patients (86.8%).

• Source:• lead or lead material cultures (63.9%), • Blood cultures (54.5%), • pocket tissue cultures (52.9%), and• pocket swab cultures (44.2%). • No growth --remaining 13.2%

Hussein et al. J A C C : C L I N I C A L E L E C T R O P H Y S I OL OG Y V O L . 2 , NO . 4 , 2 0 1 6Microbiology of CIED Infections A U G U S T 2 0 1 6 : 4 9 8 – 5 0 5


microbiology• CIED infections carry not only a significant risk of morbidity but a risk of death up to 66% if left

untreated, and this is decreased to about 18% with antibiotics and extraction

• 1 in 3 CIED infections was caused by a methicillin-resistant staphylococcal organism,• and• one-half of all staphylococcal infections are methicillin resistant.



microbiology


Trends in microbiology



Trends in microbiology



Microbiology• In general, culprit organisms in CIED infections may be acquired either from the patient’s own

skin or exogeneously from the health care environment.

• An association has been reported between pre-axillary flora and the pathogens isolated from CIED infections which supports the theory of endogenous acquisition

Da Costa, Antoine, et al. "Role of the preaxillary flora in pacemaker infections." Circulation 97.18 (1998): 1791-1795.

• disproportionate frequency of drug-resistant staphylococci in CIED infections suggests that the health care environment is the source of acquisition of these organisms

Abraham, James, et al. "Staphylococcus aureus bacteremia and endocarditis: the Grady Memorial Hospital experience with methicillin-sensitive S aureus and methicillin-resistant S aureus bacteremia." American heart journal 147.3 (2004): 536-539.


Pathogenesis• Microbial contamination of a device can occur:

• (i) during manufacture or packaging(clusters of infections/unusual environmental organisms) • (ii) prior to implantation; • (iii) during implantation; • (iv) secondary to surgical site infection; • (v)via haematogenous seeding from a distant site; or • (vi) via contamination after erosion through the skin.

• Asymptomatic colonization of ICEDs can occur with normal skin commensals and this may develop into symptomatic infection at a later stage.


Pathogenesis• 14 unused sterile ‘control’ leads were placed on the operating table during an ICED insertion

procedure and subsequently cultured; one lead (7%) was culture positive for Staphylococcus epidermidis.

• Klug, D., et al. "Local symptoms at the site of pacemaker implantation indicate latent systemic infection." Heart 90.8 (2004): 882-886.

• During implantation, there is a risk of device contamination with the patient’s own skin flora,introduced into the wound at the time of skin incision.

• Surgical site infection can progress to involve the device.

• Lakkireddy etal.EFFECT OF POVIDONE-IODINE IRRIGATION ON INFECTION,PACE 2005; 28:789–794


Pathogenesis-Device-related factors

• type of plastic polymer, irregularity of its surface, and its shape• Plastic polymers that encase medical devices, as well as the pathogens that adhere to them, are

hydrophobic. • The greater the degree of hydrophobicity, the greater is the adherence.• Polyvinyl chloride favors more adherence than Teflon (duPont, Wilmington)• some metals (eg, stainless steel) favor adherence more than others (eg, titanium). • An irregular surface of the device favors • Indirect device factors as risk factors :

• subsequent invasive manipulation of an implanted CIED and a • limited number of device implantations previously performed by the physician performing the procedure.


Pathogenesis-role of biofilm?• Biofilm is defined as a surface-associated community of 1 or more microbial species that are firmly

attached to each other and the solid surface and are encased in an extracellular polymeric matrix that holds the biofilm together

• Layers of bacteria on the surface of an implanted device are encased in this extracellular slime and constitute a biofilm.

• staphylococcus

• When a bacterial cell switches modes from free-floating (planktonic) organisms to biofilm, it undergoes a phenotypic shift in behavior in which large groups of genes are regulated.

Heilmann C etal. Molecular basis of intercellular adhesion in the biofilm-forming Staphylococcus epidermidis. Mol Microbiol. 1996;20:1083–1091




POCKET INFECTION• Generator pocket infection is

characterized by localized cellulitis, swelling, discharge, dehiscence or pain.

• Wound inflammation can be an early presentation of generator pocket infection.

• Generator pocket infection and ICED-IE or ICED lead infection (ICED-LI) frequently coexist.


clinical features of ICED infection?• Non-specific signs and symptoms of systemic infection (including fevers, chills, night sweats,

malaise and anorexia) may be the only clinical features of ICED-IE/ICED-LI.

• Only fewer than 10% of patients present with septic shock.

• Clinical diagnosis of ICED-IE/ICED-LI can be challenging and is often delayed.

• ICED-IE/ICED-LI may present with secondary foci, such as spinal or pulmonary infection.

• The Duke criteria can be used to assist the diagnosis of ICED-IE/ICED-LI.


Clinical diagnosis• The diagnosis of generator pocket infection may be simple, with obvious and easily identified local

inflammatory changes, but early post-implantation inflammatory changes brought about by a variety of processes, such as skin reactions to disinfection product

• ‘Superficial cellulitis’ may be an early presentation of generator pocket infection.


Clinical features


Clinical features• tethering around a device with

threatened erosion is usually indicative of infection

• Once the generator or proximal leads have eroded through the skin, a device should be considered infected, whatever the mechanism for erosion.


Clinical features• Generator pocket infection may be accompanied by systemic signs of infection.

• Conversely, lead infection is common in patients with symptoms and signs localized to the generator site

• It can be challenging to establish the diagnosis of ICED-LI or ICED-IE, especially in the absence of generator pocket infection, and many months may elapse between symptom onset and diagnosis


Clinical features







Microbiological sampling and processing

• Identification of the causative microorganism(s) in ICED infection is necessary to inform appropriate antimicrobial therapy;

• particularly important given the range of potential pathogens and antimicrobial resistance profiles.

• Negative blood cultures appear to be more common in ICED infection than in native valve endocarditis and do not exclude a diagnosis of infection


Which samples should be collected to establish the cause of ICED infection?

• results of all of these analyses should be considered together with clinical information

• Appropriate microbiological samples include: • culture of blood, • lead fragments (ideally distal and proximal), • lead vegetation• generator pocket tissue and • pus from a generator pocket wound

• Aspiration of a CIED pocket is discouraged because the diagnostic yield is low and because it can potentially lead to the introduction of microorganisms

• Meticulous sampling technique is essential


When should blood cultures be taken?

• Blood cultures should be taken prior to starting antimicrobial therapy.• On clinical suspicion of ICED infection:

• in pts with a chronic or subacute presentation-- 3 sets of aseptically collected, optimally filled blood cultures should be taken from peripheral sites with ≥6 h between them.

• In pts with severe sepsis or septic shock at the time of presentation--2 sets of optimally filled blood cultures should ideally be taken at different times within 1 h

• Blood cultures should be taken 48–72 h after removal of an infected ICED.

• Apply meticulous aseptic technique when taking blood cultures to reduce the risk of contamination with skin commensals


generator pocket sampling at the time of removal?• tissue ( 2 cm2) ∼ should be excised from the pocket site and sent for culture.

• Culture of tissue has been shown to have a statistically greater sensitivity than swab culture

• In the microbiology laboratory, tissue should be subjected to Gram’s stain and culture.

• It is recommended that pocket site tissue is only taken from patients who show clinical evidence of ICED infection,

• as detection of colonization (or contamination) in the absence of signs of infection is of little clinical value and may lead to unnecessary antimicrobial therapy or even surgery

Dy Chua, Jimmy, et al. "The role of swab and tissue culture in the diagnosis of implantable cardiac device infection." Pacing and clinical electrophysiology 28.12 (2005): 1276-1281.



What laboratory methods should be used during processing?• Pus samples or fluid (e.g. collected via a needle and syringe or even just a syringe from a

discharging wound) are generally more reliable than swabs for Gram staining and culture. • These samples should be plated onto a range of media (solid and liquid) to recover the most likely

pathogens


Chocolate agar 35-37 C in 5% CO2 for 48 hrs

CLED or MACCONKEY AGAR

35-37 C in air for 24 hrs

BLOOD AGAR 35-37 C IN ANAEROBIC CABINET FOR 48 HRS

ROBERTSONS COOKED MEAT BROTH

37 C AT LEAST 48 HRS

If culture of tissue sample is negative despite convincing evidence of clinical inf

Amplification of tissue and 16s bacterial rRNA.

• Lead tips should also be cultured using the media listed

• occasionally be caused by fastidious or slow-growing bacteria such as Mycobacterium spp.,Nocardia spp. and auxotrophic staphylococci



Definitions

• There are no universally agreed definitions of ICED infection

• These definitions have been synthesized from current available evidence, those used previously and by Working Party consensus.

• It may take some days to undertake clinical assessment, investigations and, in some cases


Early post-implantation inflammation

• Erythema affecting the box implantation incision site, without purulent exudate, dehiscence, fluctuance or systemic signs of infection and occurring within 30 days of implantation.

• The term ‘inflammation’ here implies that a definite diagnosis of infection has not been established and starting antimicrobial therapy is not necessarily indicated.

• There should be clinical resolution with removal of the cause within 2 weeks (e.g. if allergic reaction to local dressing/skin preparation, removing or changing the dressing/ preparation) so a period of close observation may be required.

• A small localized area (<1 cm) of erythema and or purulence associated with suture (‘stitch abscess’) is included in this group and this should resolve with removal of the suture and a short course of antimicrobial therapy, if clinically indicated.


Uncomplicated generator pocket infection

• (i) Spreading cellulitis affecting the generator site; OR • (ii) incision site purulent exudate (excluding simple stitch abscess); OR • (iii)wound dehiscence; OR • (iv) erosion through skin with exposure of the generator or leads; OR • (v) fluctuance (abscess) or fistula formation; AND• no systemic symptoms or signs of infection AND negative blood cultures.

• Note: • the term ‘generator pocket’-essentially the device and local soft tissues are involved. • A 30 day cut-off is recommended since most superficial infections present within this time frame. • A microbiological cause may be identified from pus samples.


Complicated generator pocket infection

• As for uncomplicated generator pocket infection but WITH evidence of lead or endocardial involvement, systemic signs or symptoms of infection or positive blood cultures


ICED lead infection

• Definite ICED-LI:• (i) Symptoms/signs of systemic infection

• NO signs of generator pocket infection AND echocardiography consistent with vegetation(s) attached to lead(s) AND presence of major Duke microbiological criteria.

• (ii) Symptoms/signs of systemic infection ,

• NO signs of generator pocket infection AND culture, histology or molecular evidence of infection on explanted lead.

• Possible ICED-LI:• (i) Symptoms/signs of systemic infection AND

echocardiography consistent with vegetation(s) attached to lead(s)

• BUT no major Duke microbiological criteria present.

• (ii) Symptoms/signs of systemic infection AND major Duke microbiological criteria present BUT no echocardiographic evidence of lead vegetations.




ICED-LI• ICED-LI can occur with or without evidence of generator pocket infection.

• Possible ICED-LI is a common problem; the diagnosis of ICED-LI may be strengthened by evidence of pulmonary emboli .

• Diagnosis of isolated ICED-LI, i.e. exclusion of ICED-IE, can be difficult but is possible if • the tricuspid valve is structurally normal and remains structurally normal after system removal with no remaining

vegetation seen on echocardiography following device extraction.

• The presence of right atrial lesions on echocardiography following ICED removal (fibrin sheaths, sometimes referred to as ‘ghosts’) can cause confusion and can sometimes represent a persistent source of infection requiring treatment as ICED-IE.

• If there is uncertainty, manage as for ICED-IE.



Management of ICED infection

• The aim of managing ICED infection is to cure the patient of infection, as efficiently as possible, while minimizing the risk of harm.

• Management of ICED infection should be individualized to each patient but there are clear principles,

• supported by varying degrees of evidence, to guide management plans.


Management Recommendations

Guidelines for the diagnosis, prevention and management of implantable cardiac electronic device infection. Report of a joint Working Party project on behalf of the British Society for Antimicrobial Chemotherapy (BSAC, host organization), British Heart Rhythm Society (BHRS), British Cardiovascular Society (BCS), British Heart Valve Society (BHVS) and British Society for Echocardiography (BSE). J Antimicrob Chemother 2015; 70 (2): 325-359. doi: 10.1093/jac/dku383


How should the device be managed?

• An infected ICED may be left in situ, partially removed or removed entirely.

• Partial removal: may be planned and this usually involves removal of the infected generator, cutting the leads and burying the extravascular portion in the soft tissues, leaving the leads in the heart.

• Unplanned partial removal may occur if a lead breaks during attempted removal, leaving a remnant of lead in the heart


Device Removal

• majority (usually >90%) of large, single-centre reports of ICED infections managed with device removal and appropriate antimicrobial therapy demonstrate cure with this approach,

• although relapse of infection was reported in 0%–7% of episodes

• Relapse is more common when devices are not removed; e.g. over half of patients who did not have complete removal demonstrated relapse

• Case series describe success in 82%–98% of attempted system removals for ICED infection

Le KY, Sohail MR, Friedman PA et al. Impact of timing of device removal on mortality in patients with cardiovascular implantable electronic device infections. Heart Rhythm 2011; 8: 1678–85.


Device Removal

• A linear relationship was demonstrated in one study, with a

• 5% risk of failure with a device 0–3 years old increasing to a• 20% risk of failure with a device 9–12 years old

Rusanov A, Spotnitz HM. A 15-year experience with permanent pacemaker and defibrillator lead and patch extractions. Ann Thorac Surg2010; 89: 44–50.


• Removal of a generator is usually an uncomplicated procedure compared with the risk of removing leads (which increases with the length of time that leads have been in situ) and the generator often represents the bulk of the infection burden.


Generator Pocket Infection, ICED-LI And ICED-IE?

• Complete and early (as soon as possible, but not more than 2 weeks after diagnosis) removal of an infected ICED system (generator and all leads) combined with appropriate antimicrobial therapy is the most effective, safe and efficient treatment option.

Guidelines for the diagnosis, prevention and management of implantable cardiac electronic device infection. Report of a joint Working Party project on behalf of the British Society for Antimicrobial Chemotherapy (BSAC, host organization), British Heart Rhythm Society (BHRS), British Cardiovascular Society (BCS), British Heart Valve Society (BHVS) and British Society for Echocardiography (BSE). J Antimicrob Chemother 2015; 70 (2): 325-359.

Implantable Cardiac Electronic Device InfectionWilkoff, Bruce L., et al. "Transvenous lead extraction: Heart Rhythm Society expert consensus on facilities, training, indications, and patient management: this document was endorsed by the American Heart Association (AHA)." Heart rhythm 6.7 (2009): 1085-1104.




What is the preferred means of device removal?

• Summary:• Percutaneous methods of lead removal are preferred for infected leads, combined with complete

removal of the generator.

• Open surgical removal should be considered for large lead-associated vegetations (>20 mm) and when valve surgery is indicated for other reasons.

Guidelines for the diagnosis, prevention and management of implantable cardiac electronic device infection. Report of a joint Working Party project on behalf of the British Society for Antimicrobial Chemotherapy (BSAC, host organization), British Heart Rhythm Society (BHRS), British Cardiovascular Society (BCS), British Heart Valve Society (BHVS) and British Society for Echocardiography (BSE). J Antimicrob Chemother 2015; 70 (2): 325-359.


percutaneous lead extraction• in a large UK series, the procedure was successful in over 98% of cases.

• Only the time a device had remained in situ was a risk factor for failed percutaneous removal in this series, but it is unclear whether vegetation size was included in the analysis

• Clinical practice among Working Party members in terms of the threshold for referral for surgical removal varied between 10 and 40 mm, highlighting this as an area for further study

• 3%–15% patients decline or are unsuitable for ICED removal.

• Sohail MR, Uslan DZ, Khan AH et al. Management and outcome of permanent pacemaker and implantable cardioverter-defibrillator infections. J Am Coll Cardiol 2007; 49: 1851–9.

• Klug D, Balde M, Pavin D et al. Risk factors related to infections of Implanted pacemakers and cardioverter-defibrillators: results of a large prospective study. Circulation 2007; 116: 1349–

55.



• Lead management

• refers to overall lead monitoring, management of associated complications (infection, malfunction,thrombosis, and vascular complications), issues related todevice upgrades (abandonment versus extraction), and management of device- related imaging issues (magnetic resonance imaging and delivery of radiation therapy)

• Decisions are made after assessing risk versus risk rather than risk versus benefit for individual patients


• Removal of the leads without any specialized equipment is called lead explantation, • lead removal with the use of specialized equipment (locking stylets, specialized sheaths, femoral,

or jugular extraction tools) is called lead extraction.

• Wilkoff BL Heart Rhythm Society; American Heart Association. Transvenous lead extraction: Heart Rhythm Society expert consensus on facilities, training, indications, and patient management: this document was endorsed by the American Heart Association (AHA). Heart Rhythm.2009;6:1085–1104


• Most pacemaker leads implanted within a year can be explanted without the use of any specialized equipment.

• As leads stay longer in the vascular system, fibrotic reactionoccurs around the leads, causing them to adhere to the vessel wall.

• The amount of fibrosis is dependent on the insulation materials, surface area of the implantable cardioverter-defibrillator coils, time from implantation duration, flow state in the venous system, number of the leads, and various patient specific factors such as renal insufficiency predisposing to dystrophic calcification or hypertrophic scar.

• Once fibrotic reaction occurs, attempts to remove leads with simple traction can cause major vascular or myocardial complications.


Lead extraction techniques• Current transvenous techniques were developed by Byrd and colleagues.• The lead is dissected free from the pocket; all prosthetic material (anchoring sleeve and sutures) is removed; and

the connector is cut off. • A locking stylet is inserted through the inner lead coil all the way to the tip of the lead for fixation. • Insulation and conductor materials are secured to the locking stylet with a nonstretchable suture to provide

support and to form a rail to hold countertraction on the lead. • A variety of specialized sheaths can then be advanced overthe prepared lead to dissect the fibrous tissue and free

the lead within the vasculature.

• Teflon, polypropylene, and stainless s teel sheaths were initially used but have largely been replaced by next-generation laser sheaths and rotating mechanical sheaths,which are easier and safer to use.

• The techniques for lead preparation,countertraction, and dissection remain the same regardless of the instruments used or indications for extraction.


Open surgical• indicated in patients with leads that are extravascular as a result of misplacement through arterial

structures or of erosion through the venous or myocardial wall.

• Large vegetations (>2 cm) on the lead or the tricuspid valve also warrant evaluation by a cardiac surgeon.

• Special attention should be paid to vegetation characteristics. • Vegetations large enough to block the main pulmonary artery or major branches should not be

extracted percutaneously.


Open surgical• A solid cauliflower-like vegetation should be

removed with an open surgical procedure,as opposed to a thin windsock-like vegetation that might be extracted percutaneously

• Upgrading the extraction sheath to a larger size than recommended can allow the extraction of small vegetations along with the lead.


LEAD EXTRACTION• team-based approach and a continual ongoing quality

improvement program are stressed in the consensus statement.

• A minimum extraction of 40 leads as a primary operator and an annual volume of 20 lead extractions are recommended to maintain competence.

• Involvement of a cardiothoracic surgeon well versed in managing complications arising from lead extraction is critical

• hybrid operating room is an ideal setting for lead extraction,

• HRS GUIDELINES


• An externally located temporary permanent pacing system can be implanted from the internal jugular or subclavian vein

Postextraction Management



If Removal Is Not An Option???

• Summary:• In ICED-LI, it is reasonable to attempt salvage of the device with a course of appropriate

antimicrobial therapy when the risks of removing the infected ICED are considered too high, or a patient declines system removal.

• In a patient with an infected ICED that involves generator pocket infection, in whom the risks of removing the entire device are considered too high (or a patient declines entire system removal), the

• generator should be removed, leaving the leads in situ, and • a course of appropriate antimicrobial therapy should be given.


• Excluding ‘superficial infections’, seven studies reported cure rates ranging between 13% and 71% for patients managed with partial device removal



Where should removal of infected ICEDs be undertaken?

• should only be undertaken in recognized centres with expertise in the procedure and with appropriate surgical facilities immediately available.

• Myocardial and vascular tears and cardiac tamponade are recognized complications of lead extraction, which require the immediate availability of appropriate cardiac, vascular and/or thoracic surgical facilities.

• Lead removal should not be attempted outside such centres since damage to the lead may further complicate subsequent removal attempts


How should the device be managed in skin erosion?• Erosion of skin to expose either leads or generator to the air requires removal of the entire system

• Leads or the generator can erode through the skin, often as a result of superficial positioning of the device, e.g. in very thin patients.

• Frank erosion through the skin may be preceded by ‘tethering’, where a superficial portion of lead becomes adherent to the overlying skin, often without accompanying signs of inflammation.

• ‘Pre-erosion’ is a term often used to describe inflamed skin over a superficial portion of lead.

• Once the ICED device is exposed, microbial contamination is inevitable, meaning that erosion should be treated as infection

• Repositioning of the generator box into a subpectoral position for exposed leads resulted in a 14% infection rate in a small series of seven patients

• Knepp EK, Chopra K, Zahiri HR et al. An effective technique for salvage of cardiac-related devices. Eplasty 2012; 12: e8 .


If required, when should device re-implantation take place?

• The need for and timing of a replacement ICED after removal of an infected device will depend on the indications for its use.

• Wherever possible, re-implantation should be avoided or delayed until symptoms and signs of systemic and local infection have resolved.

• The venous access sheath used for percutaneous removal of an infected or system should not be used for re-implantation of a new system.

• No part of an ICED that has been removed because of infection should be reimplanted.


• Fever at the time of device implantation is a described risk factor for subsequent device infection,

• ideally patients should be apyrexial and without other symptoms or signs of systemic infection at the time of implantation.

• • The optimal reported time to re-implantation after removal of the infected device is not known but

some advocate an interval of 7–10 days

• Klug D, Balde M, Pavin D et al. Risk factors related to infections of implanted pacemakers and cardioverter-defibrillators: results of a large prospective study. Circulation 2007; 116: 1349–55


• If the patient is not PPM dependent, the need for any ICED should be reviewed and those who require re-implantation should be observed on the ward until the procedure is considered safe.

• It would be unusual to immediately implant a new permanent ICED after removal of an infected

system, but re-implantation should occur at a new site if this is necessary.


New Lead Or New PG Or New Device???

• the practice of removing an infected ICED, placing new leads and then re-attaching the old generator after cleaning with chlorhexidine or hydrogen peroxide was described.

• Given current knowledge of sterilization procedures and the biofilm nature of ICED infection, the Working Party doubts that sterilization of an infected generator can be achieved by either of these methods and there is a high risk of transferring bacteria to the new leads.


If required, when should device re-implantation take place?

• The need for and timing of a replacement ICED after removal of an infected device will depend on the indications for its use.

• Wherever possible, re-implantation should be avoided or delayed until symptoms and signs of systemic and local infection have resolved.

• The venous access sheath used for percutaneous removal of an infected or system should not be used for re-implantation of a new system.

• No part of an ICED that has been removed because of infection should be reimplanted


Management of infected pocket after device removal• After device removal, the infected pocket… • may be partially closed and a drain inserted, or• packed with wet-to-dry dressings and left open to heal by secondary intention

• Vacuum-assisted wound closure(1997)—is being proposed• But currently there are no controlled trials showing that vacuum assisted wound closure is

superior to standard therapy for either indication.


V.A.C therapy• consists of GranuFoam sponge material placed in the

wound with a clear adhesive covering applied over the entire wound. A hole 0.5×0.5 cm is made in the occlusive dressing;

• a vacuum tube is inserted; and 125-mm Hg suction applied

• GranuFoam sponge is changed every 72 hours and promotes healing by draining the pathogens away while converting an open draining wound to a closed system

• may allow CIED reimplantation on the ipsilateral side at a shorter interval

Mulpuru et al Device Infections,Circulation. 2013;128:1031-1038.


How should temporary pacing be managed?

• pacemaker dependent, --temporary pacing until symptoms and signs of systemic infection (including fever) have resolved before implanting a permanent device.

• However, temporary pacing has been associated with an increased risk of subsequent infection

• For venous access of TPI –the pre-pectoral region contralateral to the infected site should therefore be avoided for temporary pacing access if possible.

• Lepillier A, Otmani A, Waintraub X et al. Temporary transvenous VDD pacing as a bridge to permanent pacemaker implantation in patients with sepsis and haemodynamically significant atrioventricular block. Europace 2012; 14: 981–5.


• To reduce these infection risks as well as ensuring more reliable pacing, some use permanent-type pacing leads for temporary pacing.

• The ‘permanent’ lead is tunneled under the skin and attached to an external pacemaker which is secured to the skin for the period of temporary pacing;

• when it is considered appropriate to site a permanent system the external pacemaker and permanent lead that has been used for temporary pacing are removed


• If temporary pacing via a central venous catheter is used, the choice of the venous access site for temporary pacing should take into consideration the need for a future ICED; the pre-pectoral region contralateral to the infected site should therefore be avoided for temporary pacing access if possible.


Principles of Antimicrobial treatment

• should be discussed by the multidisciplinary team and should be determined by: • plans to remove or attempt to salvage an infected ICED; • the presence of ICED-IE; and • any extra-cardiac foci of infection

• number of different antimicrobial regimens are advised in order to cover a number of different clinical scenarios.

• There is no robust trial evidence to support these antimicrobial regimens; • they are made on the basis of in vitro susceptibility data, observational studies, pharmacokinetic

and pharmacodynamic data and clinical experience


• Biofilm:

• well-established term to describe the growth of bacteria on solid surfaces and ICED infections are a typical example.

• biofilm-mediated infections have become more prominent as the use of implanted medical devices has become more common.

• Although S. aureus is a ubiquitous human pathogen and does not require prosthetic material to cause infection, it can form biofilm.

• The presence in the body of prosthetic materials, if contaminated, allows normally nonpathogenic microorganisms such as CoNS to adhere and establish a focus of infection.


• inaccessible to antimicrobials, regardless of the mode of administration to the patient, explaining why eradication is so difficult.

• Even when infection appeared to be clinically confined to the generator pocket, the intravascular sections of leads were culture positive in 72% of cases,46 illustrating how bacteria can migrate along the leads from an infected generator pocket

• Klug D et al. Local symptoms at the site of pacemaker implantation indicate latent systemic infection. Heart 2004; 90: 882–6.

• highlights the need for prompt and complete removal of infected ICEDs as a key element of therapy


Biofilm and CIED infection• The biofilm nature of ICED infection makes eradication of infection very unlikely without removal

of the device• ICED infections are a typical example for biofilm growth.

• In modern medicine biofilm-mediated infections have become more prominent as the use of implanted medical devices has become more common

• renders bacteria far more resistant to antimicrobial therapy

• Some bacteria are far more adept at sticking to non-biological materials than others, which explains e.g. the predominance of staphylococci in ICED infection and the rarity of ‘coliform’ lead infections


• Local delivery of antimicrobials into or around the generator:

• This approach has no role in the management of an infected ICED and

• Best approach--complete removal of infected devices, positioning of any new system in a different anatomical location and systemic antimicrobial therapy as per guideline recommendations

• Hansen LK, Berg K, Johnson D et al. Efficacy of local rifampin/minocycline delivery (AIGIS(RX)(R)) to eliminate biofilm formation on implanted pacing devices in a rabbit model. Int J Artif Organs 2010; 33: 627–35.

• Bloom HL, Constantin L, Dan D et al. Implantation success and infection in cardiovascular implantable electronic device procedures utilizing an antibacterial envelope. Pacing Clin Electrophysiol 2011; 34: 133–42.


close f/u-wound hygiene and avoid removal of exposed suture if any

harish oruganti

rigorous follow up needed and avoidance of


Which antimicrobial agents are recommended for ICED-LI or ICED-IE?

• Empirical regimens for ICED-LI or ICED-IE

• The need for empirical antimicrobial treatment for ICED-LI or ICED-IE (prior to the availability of microbiological data) is a clinical decision based on the severity of infection.

• The antimicrobial regimen for empirical treatment or culture-negative ICED infection needs to have activity against both Gram-positive (including methicillin-resistant staphylococci) and Gram-negative bacilli


Which antimicrobial agents are recommended for ICED-LI or ICED-IE?

• Vancomycin or daptomycin are suitable anti-Gram-positive agents for empirical treatment or for culture-negative ICED infection.

• Local resistance patterns should be considered in choosing anti-Gram-negative agents for empirical treatment of suspected ICED infection.

• Aminoglycosides (e.g. gentamicin) and meropenem are both usually appropriate.

• Modify treatment regimens once the microbial cause is identified







duration

If ICED salvage is to be attempted 6 weeks good initial clinical response to antimicrobial therapy, there is no evidence of extracardiac infection and the ICED has been removed

total of 4 weeks of therapy is usually sufficient to treat any residual native valve IE, regardless of the timing of system removal

If symptoms and signs of infection persist until the time of ICED removal, then

further 4 weeks of therapy after system removal is appropriate.

prosthetic valve endocarditis and for attempted salvage of ICEDs in the setting of associated IE or LI

Six weeks of therapy is advised


Prevention of ICED infection-Where should ICED insertion take place?

• ICED insertion should take in place in an appropriately ventilated (at least 15 but ideally 25 air changes/h), equipped and cleaned room.

• complete agreement with the previous statement that a cardiac catheterization laboratory is not an ideal environment for implantation of ICEDs.

• All apparatus that comes into contact with the patient must be appropriately decontaminated before contact. All equipment in the room should be cleanable and regularly decontaminated

• Campbell RW, Charles R, Cowan JC et al. Clinical competence in electrophysiological techniques. Heart 1997; 78: 403–12


• Does operator experience affect infection rates?

• Recommendation : Procedures, including generator change, should be performed or supervised by experienced operators as per BHRS guidelines.

• Recrudescence of bacteria inoculated during an earlier implant when exposed to blood and tissue during re-operation might also occur, but is unproven

• Comparing 30 and 60 day ICD infection incidence, physicians who implanted 1–10 devices per year had a higher complication rate than those who implanted more than 29 devices (30 days, 0.9% versus 0.4%; 90 days, 1.3% versus 0.6%, P¼0.01)

• Al-Khatib SM, Lucas FL, Jollis JG et al. The relation between patients’ outcomes and the volume of cardioverter-defibrillator implantation procedures performed by physicians treating Medicare beneficiaries. J Am CollCardiol 2005; 46: 1536–40.


• Should temporary pacing be avoided to reduce infection?

• Recommendation:Wherever possible, temporary transvenous pacing should be avoided prior to implanting a permanent ICED.

• In a prospective multicenter survey of 6319 patients to determine complications occurring within 1 year of PPM or ICD implantation, the odds ratio of infection was 2.46 (95% CI 1.09–5.13) when a temporary wire was in situ.

• Klug D, Balde M, Pavin D et al. Risk factors related to infections of implanted pacemakers and cardioverter-defibrillators: results of a large prospective study. Circulation 2007; 116: 1349–55.


• Should patients having ICED insertion or manipulation be screened for staphylococcal carriage or decolonized?

• There are no studies specifically investigating the impact of pre-procedure screening for S. aureus or decolonization therapy on ICED infection rates.

• Pre-procedural topical antimicrobial agents aimed at eliminating S. aureus are recommended for patients who are known to be colonized with S. aureus.


• How should anticoagulation be managed during ICED insertion or manipulation?

• Uninterrupted warfarin [with careful international normalized ratio (INR) monitoring] is preferable to bridging with heparin in those patients in whom interruption of anticoagulation is contraindicated.

• Where feasible , antiplatelet and/or anticoagulants should be discontinued prior to the procedure to allow a normal thrombotic/coagulation profile


Infection Control Measures• ICED insertion should be carried out using an aseptic technique, in an environment observing

operating theatre discipline, including appropriate clothing.

• Bathing or showering with soap is recommended prior to ICED insertion.

• Patients should be given specific theatre wear (including a head cap) that allows easy access to the operative site and intravenous cannulae, and provides for the patient’s comfort and dignity.

• All staff should wear theatre specific clothing in all areas where ICED procedures are undertaken. Scrub suits, cap, masks and theatre footwear are essential parts of theatre discipline.


Infection Control Measures• The operating team should wear sterile gowns in the operating theatre during ICED procedures.

• Consider wearing two pairs of sterile gloves when there is a high risk of glove perforation or the patient is known to have a chronic blood-borne viral infection.

• Staff number and movements should be kept to a minimum in the operating theatre.

• The operating team should remove hand/wrist jewellery, artificial nails and nail polish before procedures.


Infection Control Measures• The operating team should wash their hands prior to the first operation on the list using an

aqueous antiseptic surgical solution, with a single-use brush or pick for the nails, and • ensure that hands and nails are visibly clean.

• Before subsequent operations on a list, hands should be washed using either an alcoholic hand rub or an antiseptic surgical solution. If hands are soiled they should be washed again with an antiseptic surgical solution.

• Any equipment brought into the operating field should be covered to reduce the risk of contamination.

• Devices and surgical equipment should be left uncovered for the minimum possible time


skin preparation:

• For hair removal, use electric clippers (with a single-use head) on the day of the procedure.

• alcoholic chlorhexidine preparation (containing a minimum of 2% chlorhexidine) (or povidone iodine in alcohol for patients unable to tolerate chlorhexidine)

• The skin preparation should be left on for a minimum contact time of 30 s and

• should not be allowed to pool.

• Draping is recommended i.e. one large fenestrated drape can be used to cover the patient, including the head.

• use iodophor-impregnated drapes; avoid incise drapes in patients with iodine allergy.



systemic antimicrobial prophylaxis ?

• Systemic antimicrobial prophylaxis should be used prior to ICED implantation.

• best evidence of benefit of antimicrobial prophylaxis comes from a trial using cefazolin as the active agent.

• De Oliveira JC et al. Efficacy of antibiotic prophylaxis before the implantation of pacemakers and cardioverter defibrillators:results of a large, prospective, randomized, double-blinded,placebo-controlled trial. Circ Arrhythm Electrophysiol 2009; 2: 29–34.


Timing of prophylaxis?

• Intravenous antimicrobials should be administered within 1 h prior to skin incision.

• Repeat dosing of antimicrobials is not recommended after skin closure

• Darouiche R, Mosier M, Voigt J. Antibiotics and antiseptics to prevent infection in cardiac rhythm management device implantation surgery. Pacing Clin Electrophysiol 2012; 35: 1348–60.


Which agent(s) should be given?

• The choice of prophylactic agent should cover the most likely pathogens in ICED infection. [C]

• A glycopeptide (e.g. intravenous teicoplanin, according to local dosing protocols) is the current preferred agent (with or without gentamicin depending on local Gram-negative infection rates)

• If a glycopeptide is to be used, teicoplanin has some practical advantages over vancomycin in terms of administration as it can be given as a bolus rather than a long infusion.

• Hope R, Livermore DM, Brick G et al. Non-susceptibility trends among staphylococci from bacteraemias in the UK and Ireland, 2001–06. J Antimicrob Chemother 2008; 62 Suppl 2: ii65–74.


• Should antimicrobials be instilled into the generator pocket after implantation?

• Local instillation of antimicrobials or antiseptics should be avoided until evidence of benefit has been demonstrated.

• Antimicrobial ‘envelopes’


• TYRX™ ANTIBACTERIAL ENVELOPES

• Minocycline and rifampin elute locally into the tissue pocket enabling Mic tissue concentration levels to be reached within 2 hours of implantation,

• maintained for a minimum of 7 days: locally delivered, adjunctive antibacterial protection.

• Novel, large-pore mesh knitted from bioabsorbable multifilaments coated with a bioabsorbable polyarylate polymer that breaks down into naturally occurring components

• Generally regarded as safe (Gras) over ~9 wks.

• composition of the mesh filament is similar to bioabsorbable suture.

Huntingdon Life Sciences Study TR -2013-001.


• Which operative factors influence risk of infection?• There is no evidence to guide the method of haemostasis or the use of capsulectomy during ICED

implantation or replacement and further research is warranted

• Haematoma formation (after implantation) is a recognized risk factor for ICED infection and haemostasis is therefore important.

• DIATHERMY:• meta-analysis of six trials undertaken by NICE found no significant difference in SSI rates when

diathermy was compared with scissors or scalpel for skin incision for a range of procedures.


• Which operative factors influence risk of infection?

• If a patient has limited subcutaneous tissue and/or poor nutrition and is at increased risk for erosion, a retropectoral pocket should be considered.

• In a survey of pediatric patients, 9 (13.8%) of 65 with subcutaneously placed device-pocket transvenous systems developed infection compared with none of the 82 who underwent retropectorally placed systems.

• Cohen Mietal. Pediatric pacemaker infections: twenty years of experience. J Thorac Cardiovasc Surg. 2002;124:821– 827.


Pocket Hematoma • prevention of hematoma during the procedure is desirable, and several interventions have been used, although

there are no data to support their role

• achieved by meticulous cautery of bleeding sites and

• packing the pocket with antibiotic-soaked oversized sponges to provide tamponade

• The application of topical thrombin may be helpful, particularly in anticoagulated patients.

• Irrigation of the pocket is useful to remove debris and may reveal persistent bleeding that could lead to pocket hematoma

• Flushing with an antimicrobial-containing solution for pocket cleansing and sponge packing


• Use of monofilament suture for closure of the subcuticular layer may avoid superficial postoperative cellulitis.

• A pressure dressing applied for 12 to 24 hours after skin closure and dressing may further decrease the risk of hematoma formation.

• In the immediate postoperative period, recent data indicate that low-molecular-weight heparin predisposes to hematoma formation and should be avoided.

• In some circumstances (e.g. sparse subcutaneous tissue, large generator, impending erosion from a previous device, concerns about cosmetic appearance) the generator may be placed subpectorally or under the breast.


Hematoma management• Optimal management of hematoma formation post-ICED insertion is not known. • Hematoma progression, excessive pain, and stress on the suture line may require hematoma

evacuation.• A hematoma should be evacuated only when there is increased tension on the skin.

• Needle aspiration should otherwise be avoided because of the risk of introducing skin flora into the pocket and subsequent development of infection.


• What represents ideal post-operative wound closure and care?

• No specific recommendations concerning wound closure and care can be made • NICE clinical guideline found no evidence that the type of suture material, or wound closure

methods had an impact on rates of SSI, but the evidence is limited and further research was advised


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Date post:	12-Apr-2017
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cardiac implantable electronic device infections

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