Pacemaker infections. A 2-year follow-up of antibiotic prophylaxis

Reduced incidence of CIED infections with peri- and post-operative antibiotic use in CRT-P/D and ICD procedures

Higher cardiac implantable electronic device (CIED) infection incidence has been observed with cardiac resynchronization therapy pacemaker/defibrillator (CRT-P/D) and implantable cardioverter defibrillator (ICD) devices compared to traditional pacemakers with a 1.2% rate reported at 1 year. CIED infection management has high morbidity/mortality. A previous study from this institution demonstrated significantly reduced CIED infection rate when peri/post-operative antibiotics were given for traditional pacemaker procedures. The present study examines CIED infection incidence following peri/post-operative antibiotics during CRT-P/D and ICD procedures. All patients who underwent CRT-P/D and ICD procedures from 1996 to 2015 received IV cephalexin/clindamycin pre- and 8-hours post-procedure followed by 5 days of oral therapy. There were 427 procedures (CRT-P = 146 (34.2%); CRT-D = 142 (33.3%); ICD = 139 (32.6%)). Mean age at time of procedure was 61.6 years. Mean follow-up duration was 4.26 years. CIED infection occurred in 6 patients (ICD = 4, CRT-P = 1, CRT-D = 1), amounting to a rate of 4.96/1000 device-years in total. Times to CIED infection from procedure were: 1.7, 3.5, 6.7, 7.3, 7.9 and 9.2 years. Five out of 6 infections occurred in patients with repeat procedures. This study demonstrates that administration of peri- followed by post-operative antibiotics during CRT-P/D and ICD procedures is associated with a very low rate of CIED infection. This rate of 4.96 infections per 1000 device-years compares favorably to contemporary rates of 8.9 infections per 1000 device-years. Most CIED infections occur late and well-beyond the 1-year follow-up of the Prevention of Arrhythmia Device Infection Trial, the largest trial on this question. This approach should be considered pending a definitive trial.

A 19-year study on pacemaker-related infections: a claim for using postoperative antibiotics

BACKGROUND

Although the incidence of pacemaker-related infection (PMINF) is low, it necessitates removal of the pacing system. There is currently no consensus on antibiotics during implantation.

METHODS

A prospective database on patients undergoing pacemaker surgery from 1991 to 2009 was reviewed to determine factors associated with PMINF. Specifically, three eras of antibiotic use were compared to elucidate the effect of antibiotics on PMINF: no antibiotics, perioperative antibiotics, and peri- plus postoperative antibiotics.

RESULTS

There were 3,253 procedures with PMINF identified in 46 (1.4%) patients. Over 19 years, PMINF incidence fell from 3.6% (no antibiotics) to 2.9% (perioperative antibiotics), to 0.4% (peri- plus postoperative antibiotics). On univariate analysis, the following were associated with PMINF: nonuse of postoperative antibiotics (3.0% vs 0.4%, P < 0.001), year of implant (P < 0.001), repeat procedures (2.3% vs 1%, P = 0.006), nonuse of perioperative antibiotics (3.6% vs 1.3%, P = 0.027). With postoperative antibiotics, rates were significantly reduced in new implants (1/1,289 = 0.1% vs 22/967 = 2.3%, P < 0.001) and repeat procedures (7/692 = 1.0% vs 16/305 = 5.2%, P < 0.001). On multivariate analysis, the following were significant (standardized coefficients denote relative importance): postoperative antibiotics (0.776), repeat procedures (0.508), year of implant (0.142), perioperative antibiotics (0.088).

CONCLUSIONS

The PMINF rate is reduced significantly by perioperative antibiotics with a further significant reduction with postoperative antibiotics. However, the reduction in PMINF rate could be a result of changes in practice in the different time eras. This study suggests consideration of perioperative followed by postoperative antibiotics to minimize pacemaker infections.

Analysis of extracted cardiac device leads for bacteria type: clinical impact

The use of cardiac implantable electronic devices (CIED) increased over time, followed by rise of CIED-related complications, mainly infections and malfunctions. A clear diagnosis of CIED infection is of pivotal importance. When infection is confirmed, transvenous lead extraction (TLE) becomes mandatory, with associated risks and mortality. Local lesions at the device pocket often return negative swabs and tissue specimens, but conservative interventions are inconclusive, raising risks of systemic dissemination of infection and difficulties of subsequent TLE any more. When local bacteriological analyses are positive, once again, a contamination effect cannot be excluded. So traditional local swabs and tissue specimens exhibit low sensitivity and specificity for diagnosis of CIED infection. On the contrary, in cases sepsis, blood samples show high specificity, while the sensibility remains low, due to possible negative results in patients on antibiotics. In this scenario, the analysis of extracted device leads seems more appropriate for diagnostic purposes.

Pacing device therapy in infants and children: a review

The number of pediatric pacemakers implanted is still relatively small. Children requiring pacing therapy have characteristics that are distinct from those of adults, including physical size, somatic growth, and cardiac anomalies. Considering these features, long-term follow-up of pediatric pacemaker implantation is necessary. Selection of appropriate generators, pacing modes, pacing sites, and leads is important. Generally, epicardial leads are commonly used in small infants. On the other hand, the use of endocardial leads in children is increasing worldwide because of their benefits over epicardial leads, such as minimal invasiveness, lower pacing threshold, and longer generator longevity. Endocardial leads are not suitable for patients with intracardiac shunts because of the high risk of systemic thrombosis. Venous occlusion is another significant problem with endocardial leads. With the increase in the number of pacing device implantations, the incidence of infection from such devices is also increasing. Complete device removal is sometimes recommended to treat device infection, but experience in the removal of endocardial leads in children is still scarce. This article gives an overview of pacing therapy in the pediatric population, including discussions on new pacing systems, such as remote monitoring systems, magnetic imaging compliant pacemaker systems, and leadless pacing devices.

Risk factors for infection of implantable cardiac devices: data from a registry of 2496 patients

AIMS

The increased use of implantable cardiac devices has been accompanied by an increase in infection. However, risk factors for infection of implanted devices are poorly documented. We aimed to identify risk factors in patients with long-term follow-up after implantation of cardiac devices.

METHODS AND RESULTS

Patients with first implantation of a cardiac device in our centre between October 1996 and July 2007 were entered in a registry. Each confirmed infection of the implanted device was matched to two controls for age, sex, and implantation year. We recorded cardiovascular risk factors (hypertension, diabetes), previous history of heart disease, renal failure, antiplatelet or anticoagulant therapy, as well as pre- and post-procedural characteristics (antibiotic prophylaxis, hyperthermia, number of leads, associated interventions, and early complications). During the study period, 2496 patients underwent implantation of a cardiac device; 35 infections were diagnosed (1.2%). Among these, 75% occurred during the first year after implantation. Early non-infectious complication requiring surgical intervention was observed only in patients with infection (9 of 35, P < 0.001). Factors independently associated with infection were diabetes [odds ratio (OR) 3.5, 95% confidence interval (CI) [1.03, 12.97]], underlying heart disease (OR 3.12, 95% CI [1.13; 8.69]), and use of >1 lead (OR 4.07, 95% CI [1.23, 13.47]). These latter two risk factors were also independently associated with occurrence of infection within 1 year of implantation.

CONCLUSION

Our data show that the presence of diabetes and underlying heart disease are independent risk factors for infection after cardiac device implantation. As regards procedural characteristics, the use of several leads and early re-intervention are associated with a higher infection rate.

The Impact of Povidone-Iodine Pocket Irrigation Use on Pacemaker and Defibrillator Infections

BACKGROUND

Infection is a devastating complication of permanent pacemakers (PMs) implantable cardioverter defibrillators (ICDs). Many implanting physicians commonly use povidone-iodine solution to irrigate the device pocket before implanting the device. We sought to assess if such a measure would alter the rate of infection.

METHODS

A total of 2,564 consecutive patients who received implantable PM or ICD devices between 1994 and 2002 were studied. Povidone-iodine was used for pocket irrigation in 53% and saline in 47%. A total of 18 (0.7%) patients developed pocket infections with 0.7% (10/1,359) in povidone-iodine (group I) and 0.6% (8/1,205) in saline (group II) pocket irrigation (p = ns). Groups I and II were studied for various clinical and demographic variables described in the results section.

RESULTS

There was no statistical difference in the baseline demographic and clinical characteristics between groups I and II, respectively. ICDs were most frequently infected than PMs (56% vs 44%). Most (83%) of the devices were dual chamber. Reopening of the pocket for either lead or generator replacement had a higher incidence of infection than new implants (61% vs 39%). There was no difference in the use of preimplantation antibiotic prophylaxis. Late (61%) and deep pocket infections (78%) were more common than early (39%) and superficial infections (22%). Blood cultures were positive in 67% and Staphylococcus aureus was the common most pathogen (50%). The mean duration of antibiotics use after the diagnosis of device infection was 35 +/- 23 days with 72% requiring device explantation. The device was reimplanted on the contralateral side in 56% cases. One patient in each group died due to device infection and related complications. No significant allergy to iodine was seen in either group.

CONCLUSION

Povidone-iodine irrigation of the subcutaneous pocket did not alter the rates of pocket infection after pacemaker/defibrillator implantation.

Pacemaker lead infection in young patients

Transvenous pacing has become widespread in the pediatric population, but related pacemaker lead infection in young patients has rarely been reported. To determine prevalence and optimal management of pacemaker lead infection in children and young adults, the authors reviewed their pacing database including 4476 patients who previously had pacemaker implantations from 1975 to 2001. A pacemaker was implanted in 304 patients under the age of 40. Of these patients 217 of them had congenital heart disease: 108 with structural defect, 109 without (mainly complete AV blocks). Among patients with congenital heart disease, 12 developed a pacemaker lead infection (5.5%, 6 patients with structural defect, 6 without). This incidence was significantly higher than in patients < 40 years at first implantation without congenital heart disease (2.3%) and in > 40-year-old patients(1.2%, P < 0.001). However, the number of reinterventions at the pulse generator site was higher in patients having had their first implantation before the age of 40. In patients with structural cardiac defect: two died after surgical lead extraction and one died before the scheduled lead extraction. The three remaining patients had successful surgical (n = 1) or percutaneous (n = 2) lead extractions. In patients without structural cardiac defect successful percutaneous extraction (5/6) or surgical extraction (1/6 with vegetation > 25 mm) was performed. One patient with percutaneous extraction developed chronic cor pulmonale during follow-up. One infection recurred in one patient with structural cardiac defect although complete removal of the pacing material had been performed. The prevalence of pacemaker lead infection is higher in younger patients, perhaps in part due to a higher number of procedures at the pacemaker site than in the general population of patients with a pacemaker. Patients with structural cardiac defect who underwent surgical lead removal were at high risk for death. Patients with percutaneous lead extraction may develop cor pulmonale.

Pediatric pacemaker infections: twenty years of experience

OBJECTIVE

We sought to evaluate possible predictors of early and late pacemaker infections in children.

METHODS

A review was performed of all pacemakers implanted in children at The Children's Hospital of Philadelphia between 1982 and 2001. Infections were classified as superficial cellulitus, deep pacemaker pocket infection necessitating removal, or positive blood culture without an identifiable source.

RESULTS

A total of 385 pacemakers (224 epicardial and 161 endocardial) were implanted in 267 patients at 8.4 +/- 6.2 years. All 2141 outpatient visits were reviewed (median follow-up, 29.4 months; range, 2-232 months). There were 30 (7.8%) pacemaker infections: 19 (4.9%) superficial infections; 9 (2.3%) pocket infections; and 2 (0.5%) isolated positive blood cultures. All superficial infections resolved with intravenous antibiotics. The median time from implantation to infection was 16 days (range, 2 days-5 years). Only 1 deep infection occurred after primary pacemaker implantation. Six patients with deep infections were pacemaker dependent and were successfully managed with intravenous antibiotics, followed by lead-generator removal and implantation of a new pacemaker in a remote location. In univariate analyses trisomy 21 (relative risk, 3.9; P <.01), pacemaker revisions (relative risk, 2.5; P <.01), and single-chamber devices (relative risk, 2.4; P <.05) were identified as predictors of infection. However, in multivariate analyses only trisomy 21 and pacemaker revisions were predictors.

CONCLUSIONS

The incidences of superficial and deep pacemaker infections were 4.9% and 2.3%, respectively. Trisomy 21 and pacemaker revisions were significant risk factors in the development of infection after pacemaker implantation. For primary pacemaker implantation, the risk of infection requiring system removal is low (0.3%).

A randomized trial comparing heparin initiation 6 h or 24 h after pacemaker or defibrillator implantation

OBJECTIVES

The purpose of this randomized study was to evaluate the prevalence of pocket hematomas in patients treated with heparin 6 h or 24 h after pacemaker or defibrillator implantation.

BACKGROUND

The risks of pocket hematoma and need for evacuation after device implantation have not been defined in patients who require anticoagulation.

METHODS

Forty-nine consecutive patients with an indication for anticoagulation with heparin after implantable defibrillator or pacemaker implantation were randomized to receive intravenous heparin either 6 h (n = 26) or 24 h (n = 23) postoperatively. Both groups also received warfarin on a daily basis starting the evening of surgery. Twenty-eight patients who received postoperative warfarin alone and 115 patients who did not receive anticoagulation were followed up in a study registry.

RESULTS

A pocket hematoma developed in 6 of 26 patients (22%) who were treated with intravenous heparin 6 h postoperatively, as compared with 4 of 23 patients (17%) who were treated with intravenous heparin 24 h postoperatively (p = 0.7). In total, a pocket hematoma developed in 10 of 49 patients (20%) treated with heparin, 1 of 28 patients (4%) treated with warfarin alone and 2 of 115 (2%) patients who received no anticoagulation (p < 0.001).

CONCLUSIONS

Intravenous heparin initiation 6 h or 24 h after pacemaker or defibrillator implantation is associated with a 20% prevalence of pocket hematoma formation. Warfarin therapy or no anticoagulation is associated with only a 2% to 4% risk of pocket hematoma formation.

Acute complications of permanent pacemaker implantation: their financial implication and relation to volume and operator experience

Complication rates after pacemaker implantation decline after increasing operator experiences (total cases), activity (cases per year), and facility with cephalic vein cutdown technique. The incremental cost of care is driven by hospital resource utilization and does not parallel medical severity.

[Secondary infections after pacemaker implantation]

INTRODUCTION

Infectious complications following pacemaker implantation are not common but may be particularly severe. Localized wound infections at the site of implantation have been reported in 0.5% of the cases in the most recent series, with an average of about 2%. The incidence of septicemia and infectious endocarditis is lower, about 0.5% of the cases. The operator's experience, the duration of the procedure and repeat procedures are considered to be predisposing factors.

CURRENT KNOWLEDGE AND KEY POINTS

The main cause of these infections has been recently demonstrated to be local contamination during implantation. The commonest causal organism is Staphylococcus (75 to 92% of the cases), Staphylococcus aureus being the cause of acute infections (less than 6 weeks), whereas Staphylococcus epidermidis is associated with cases of secondary infection (more than 2 months). The usual clinical presentation is infection at the site of the pacemaker but other forms such as abscess, endocarditis, rejection of the implanted material, septic emboli or phlebitis have been described. The diagnosis is confirmed by local and systemic biological investigations and by echocardiography (especially transesophageal echocardiography) in cases of right heart endocarditis. There are two axes of treatment: bactericidal double antibiotherapy and surgical ablation of the infected material either percutaneously or by cardiotomy.

FUTURE PROSPECTS AND PROJECTS

A recent meta-analysis supported the role of systematic, preoperative, prophylactic antibiotic therapy in the prevention of these complications. These data should be confirmed by suitably powered clinical trials.

Complications related to permanent pacemaker therapy

This study evaluates complications related to permanent endocardial pacing in the era of modern pacemaker therapy. There is only limited information available about the complications related to modern cardiac pacing. Most of the existing data are based on the 1970s and are no longer valid for current practice. The recent reports on pacemaker complications are focused on some specific complication or are restricted to early complications. Thus, there are no reports available providing a comprehensive view of complications related to modern cardiac pacing. Four hundred forty-six patients, who received permanent endocardial pacemakers between January 1990 and December 1995 at Kuopio University Hospital, were reviewed retrospectively using patient records. Attention was paid to the occurrence of any complication during the implantation or follow-up. An early complication was detected in 6.7%, and 4.9% of patients were treated invasively due to the early complication. Late complication developed in 7.2% and reoperation was required in 6.3% of the patients. Complications related to the implantation procedure occurred in 3.1%. Inadequate capture or sensing was observed in 7.4% of the patients. Pacemaker infection was detected in 1.8% and erosion in 0.9% of the patients. An AV block developed in 3.6% (1.6%/year) patients who received an AAI(R)-pacemaker due to sick sinus syndrome. There was no mortality attributable to pacemaker therapy. A great majority (68%) of the complications occurred within the first 3 months after the implantation. Complications associated to modern permanent endocardial pacemaker therapy are not infrequent. Eleven percent of patients needed an invasive procedure due to an early or late complication.

Pacemaker infective endocarditis

We identified 33 patients with definite pacemaker endocarditis--that is, with direct evidence of infective endocarditis, based on surgery or autopsy histologic findings of or bacteriologic findings (Gram stain or culture) of valvular vegetation or electrode-tip wire vegetation. Most of the patients (75%) were > or = 60 years of age (mean 66 +/- 3; range 21 to 86). Pouch hematoma or inflammation was common (58%), but other predisposing factors for endocarditis were rare. At the time that pacemaker endocarditis was found, the mean number of leads was 2.4 +/- 1.1 (range 1 to 7). The interval from the last procedure to diagnosis of endocarditis was 20 +/- 4 months (range 1 to 72). Endocarditis appeared after pacemaker implantation, early (< 3 months) in 10 patients and late (> or = 3 months) in 23 patients. Fever was the most common symptom, being isolated in 36%, associated with a poor general condition in 24%, and associated with septic shock in 9%. Transthoracic echocardiography showed vegetations in only 2 of 9 patients. Transesophageal echocardiography demonstrated the presence of lead vegetations (n = 20) or tricuspid vegetations (n = 3) in 23 of 24 patients (96%; p <0.0001 compared with transthoracic echocardiography). Pulmonary scintigraphy showed a typical pulmonary embolization in 7 of 17 patients (41%). Pathogens were mainly isolated from blood (82%) and lead (91%) cultures. The major pathogens causing pacemaker endocarditis were Staphylococcus epidermidis (n = 17) and S. aureus (n = 7). S. epidermidis was found more often in early than in late endocarditis (90% vs 50%; p = 0.05). All patients were treated with prolonged antibiotic regimens before and after electrode removal. Electrode removal was achieved by surgery (n = 29) or traction (n = 4). Associated procedures were performed in 9 patients. After the intensive care period, only 17 patients needed a new permanent pacemaker. Overall mortality was 24% after a mean follow-up period of 22 +/- 4 months (range 1 to 88). Eight patients who were significantly older (74 +/- 3 vs 63 +/- 3 years; p = 0.05) died < or = 2 months after electrode removal, whereas 25 were alive and asymptomatic.

Successful percutaneous extraction of pacemaker leads with a novel (VascoExtor) pacing lead removal system

A new pacing lead extraction system (VascoExtor, VascoMed, Germany) with a universally applicable locking stylet was used over a period of 12 months to extract 25 permanent pacemaker leads (mean implantation time 3.9 +/- 3.8 years) in 16 patients who had pacemaker infection (n = 13), lead dysfunction (n = 2), or before an automatic defibrillator implant (n = 1). With use of this system, we were able to successfully and safely remove 24 of 25 chronic pacing leads (96%) in 15 of 16 patients (93%) with sole use of the locking stylet in 81%, and with use of an array of ancillary tools in the remaining 19% of patients.

Postcardiac surgery infections

Infections following cardiac surgery, although generally uncommon, are associated with difficult management decisions and significant morbidity and mortality. They often present while the patient is either in a critical care unit, or requires CCU management. This review analyzes infections related to median sternotomy wounds, prosthetic heart valves, transvenous permanent pacemakers, automatic implantable cardioverter-defibrillators, and left ventricular assist devices. The diagnosis, microbiology, treatment and outcome of each is also discussed.

Removal of infected dual chambered transvenous pacemaker and implantation of a new epicardial dual chambered device with cardiopulmonary bypass: experience with seven cases

Seven patients with infected transvenous dual chambered pacemakers have undergone removal of the device using cardiopulmonary bypass. There were four women and three men with a mean age of 58 years. Six patients had localized infection in the generator pocket (mean of 4.6 previous unsuccessful operations for surgical sterilization). Four infections were due to Staphylococcus epidermidis, two to Staphylococcus aureus, and one patient presented septicemia caused by Staphylococcus epidermidis and Pseudomonas aeruginosa. The atrial and ventricular transvenous electrodes were removed under direct vision using cardiopulmonary bypass. A new dual chambered epicardial pacemaker was implanted. The procedure was well-tolerated, and all patients are infection free with working pacemakers after a mean follow-up of 25.4 months.

Prophylactic mezlocillin-netilmicin combination in permanent transvenous cardiac pacemaker implantation: a single-center, prospective, randomized study

A prospective, randomized study was carried out in order to assess the efficacy and safety of the mezlocillin-netilmicin combination in the prophylaxis of first permanent transvenous cardiac pacemaker implantation. Five hundred and fifty-two consecutive patients were randomly administered either 2 g mezlocillin and 200 mg netilmicin both as an i.v. bolus before implantation or 2g mezlocillin before and then 6 and 12 hours after surgery and 200 mg netilmicin before and then 12 hours after implantation. No adverse events were seen. Neither pocket nor electrode infections were observed in the 457 subjects still alive (mean follow-up: 29.2 months) or in patients who died after 1 year of follow-up (mean follow-up: 20.1 months) or before this time (mean follow-up: 4.7 months). The serum and pocket concentrations of mezlocillin and netilmicin at the end of surgery were found to be adequate to cover microorganisms that most often cause infections, including methicillin-resistant staphylococci.

Correcting a block?: successful experience of a small British pacing centre

The establishment of a local permanent pacemaker service in a district general hospital increased the pacemaker implantation rate from 22 per million population per year to 152 per million population per year over the first 6 years of the service. Forty eight per cent of patients were referred by general practitioners and 52% by hospital specialists. Single chamber demand pacing (VVI) was used exclusively. Indications for pacing and complications were comparable to those of specialist cardiac centres. Management of symptomatic bradycardia by cardiac pacing in the United Kingdom may be facilitated by further development of small pacing centres.

Antibiotic prophylaxis in pacemaker surgery: a prospective double blind trial with systemic administration of antibiotic versus placebo at implantation of cardiac pacemakers

In a double blind clinical trial, 106 consecutive patients scheduled for pacemaker implantation were randomly assigned either to a systemic prophylaxis group (SPG) (to be given flucloxacillin) or to a control group who would be given a placebo (CPG). The SPG group received 2 g IV flucloxacillin 1 hour before the operation, then 1 g perorally every 8 hours for the next five days. In the CPG group, placebo infusions and tablets were given at the same schedule. There were a total of 106 patients (SPG 52, CPG 54) who met the criteria of the study. Of these, 102 patients (SPG 50, CPG 52) completed a follow-up of 7-35 months. Infection of the pacemaker system was not diagnosed in any patient in either group. Tissue fluid was drawn 24 hours postoperatively from the pacemaker pocket for culture and for determination of pocket antibiotic concentration. The mean flucloxacillin concentration of pocket fluid from 23 patients in the SPG was 7.5 micrograms/ml. The bacteriological cultures were positive in 9/32 patients in the SPG group and in 10/34 patients in the CPG group. This study suggests that antibiotic prophylaxis need not routinely be given at implantation of permanent pacemaker systems.