Infected transvenous permanent pacemakers: role of transesophageal echocardiography

Stenotrophomonas maltophilia Endocarditis of an Implantable Cardioverter Defibrillator Lead

Stenotrophomonas maltophilia (S. maltophilia) is a nosocomial pathogen and a rare cause of infective endocarditis (IE). Given the intrinsic resistance to many classes of antibiotics, IE due to S. maltophilia carries significant morbidity and mortality among the cases described. Prompt identification of risk factors, particularly the use of medical devices, is necessary for the timely identification of this organism and prompt medical management. We report a case of an implantable cardioverter defibrillator (ICD) lead associated IE due to S. maltophilia and discuss the diagnosis, treatment and outcomes in relation to existing evidence.

Risk Factors Related to Infections of Implanted Pacemakers and Cardioverter-Defibrillators

Background— The Prospective Evaluation of Pacemaker Lead Endocarditis study is a multicenter, prospective survey of the incidence and risk factors of infectious complications after implantation of pacemakers and cardioverter-defibrillators.

Methods and Results— Between January 1, 2000, and December 31, 2000, 6319 consecutive recipients of implantable systems were enrolled at 44 medical centers and followed up for 12 months. All infectious complications were recorded, and their occurrence was related to the baseline demographic, clinical, and procedural characteristics. Among 5866 pacing systems, 3789 included 2 and 117 had >2 leads; among 453 implantable cardioverter-defibrillators, 178 were dual-lead systems. A total of 4461 de novo implantations occurred and 1858 pulse generator or lead replacements. Reinterventions were performed before hospital discharge in 101 patients. Single- and multiple-variable logistic regression analyses were performed to identify risk factors; adjusted odds ratios (aORs) and 95% confidence intervals (CIs) were calculated. At 12 months, device-related infections were reported in 42 patients (0.68%; 95% CI, 0.47 to 0.89). The occurrence of infection was positively correlated with fever within 24 hours before the implantation procedure (aOR, 5.83; 95% CI, 2.00 to 16.98), use of temporary pacing before the implantation procedure (aOR, 2.46; 95% CI, 1.09 to 5.13), and early reinterventions (aOR, 15.04; 95% CI, 6.7 to 33.73). Implantation of a new system (aOR, 0.46; 95% CI, 0.24 to 0.87) and antibiotic prophylaxis (aOR, 0.4; 95% CI, 0.18 to 0.86) were negatively correlated with risk of infection.

Conclusions— This study identified several factors of risk of device infection and confirmed the efficacy of antibiotic prophylaxis in recipients of new or replacement pacemakers or implantable cardioverter-defibrillators.

Septicémie récidivante après extraction incomplète de sondes de stimulateur cardiaque

INTRODUCTION

Septicaemia on endocardial pacemaker leads is very rare but the presentation is insidious and the prognosis very bad if all the implanted materiel is not completely removed.

OBSERVATION

A 55 year-old woman presented three episodes of Staphylococcus epidermidis septicaemia in three years, after incomplete removal of the pacing system. Permanent cure was finally obtained after complete removal of the pacemaker material.

COMMENT

Emphasis must be placed on the difficulty in diagnosing and treating such affections, their severity and also the interest of a certain number of prophylactic measures.

Endocardial pacemaker or defibrillator leads with infected vegetations: a single-center experience and consequences of transvenous extraction

BACKGROUND

Removal of infected endovascular leads if often required for cure of systemic infection, but the perceived risk of embolic events in the presence of large (>10 mm) vegetations has been considered a relative contraindication to transvenous removal. Surgical removal of pacemaker leads has been suggested in this situation to avoid occurrence of pulmonary embolization.

METHODS

Of 38 patients with infection of implanted pacemaker or cardioverter-defibrillator devices, those with evidence for systemic infection underwent transesophageal echocardiography to assess for the presence of vegetations.

RESULTS

Vegetations on endocardial leads or right-sided cardiac structures ranging in size from 10 mm to 38 mm in their largest dimension were detected in 9 patients. All patients underwent successful transvenous removal of endocardial leads. Five of 9 patients (55%) had evidence of pulmonary embolism. However, all 5 patients made a full recovery with antibiotic treatment and anticoagulation. Among patients with endocardial vegetations, there was no difference in hospitalization periods between those with or without pulmonary embolism (14.6 +/- 0.8 days vs 18.0 +/- 4.5 days, P =.7).

CONCLUSIONS

Transvenous removal of infected pacemaker leads is an alternative to open-thoracotomy removal of infected leads. Fifty-five percent of patients with vegetations on endocardial leads in our series experienced pulmonary embolism, but neither survival nor length of hospital stay were affected by this complication.

Staphylococcus aureus bacteremia in patients with permanent pacemakers or implantable cardioverter-defibrillators

BACKGROUND

Although cardiac device infections (CDIs) are a devastating complication of permanent pacemakers or implantable cardioverter-defibrillators, the incidence of CDI in patients with bacteremia is not well defined. The objective of this study was to determine the incidence of CDI among patients with permanent pacemakers or implantable cardioverter-defibrillators who develop Staphylococcus aureus bacteremia (SAB).

METHODS AND RESULTS

A cohort of all adult patients with SAB and permanent pacemakers or implantable cardioverter-defibrillators over a 6-year period was evaluated prospectively. The overall incidence of confirmed CDI was 15 of 33 (45.4%). Confirmed CDI occurred in 9 of the 12 patients (75%) with early SAB (<1 year after device placement). Fifteen of 21 patients (71.5%) with late SAB (>/=1 year after device placement) had either confirmed (6 of 21, 28.5%) or possible (9 of 21, 43%) CDI. In 60% of the patients (9 of 15) with confirmed CDI, no local signs or symptoms suggesting generator pocket infection were noted.

CONCLUSIONS

The incidence of CDI among patients with SAB and cardiac devices is high. Neither physical examination nor echocardiography can exclude the possibility of CDI. In patients with early SAB, the device is usually involved, and approximately 40% of these patients have obvious clinical signs of cardiac device involvement. Conversely, in patients with late SAB, the cardiac device is rarely the initial source of bacteremia, and there is a paucity of local signs of device involvement. The cardiac device is involved, however, in >/=28% of these patients.

[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.

The changing face of endocarditis: report of a series of cases

A 67-year-old man presented with a sudden onset right homonymous hemianopia associated with a swinging pyrexia and a new early diastolic parasternal murmur. He had had a Bjork–Shiley aortic valve replacement 2 years previously for symptomatic aortic stenosis with a transvalvular gradient of 80 mmHg and had been well thereafter.

Computed tomography scan of the brain showed a left occipital infarct (Figure 1), C-reactive protein was 51 mg/litre (normal <10 mg/litre), blood cultures consistently grew Candida parafilaris, and treatment with intravenous liposomal amphotericin and flucytocine was started the day the first positive culture was obtained. Transoesophageal echocardiography did not demonstrate vegetations, but did show a periprosthetic aortic incompetent leak.

On day 11 the aortic prosthesis was removed and replaced because of worsening aortic incompetence. Direct inspection of the prosthesis demonstrated a vegetation on the sewing ring. The immediate postoperative recovery period was complicated by complete heart block requiring insertion of a permanent pacemaker after an initial phase of pericardial pacing.

The intravenous antifungals were discontinued after 37 days of treatment and the patient commenced on lifelong oral fluconazole. At discharge on day 42 the patient was well and apyrexial with C-reactive protein less than 10 mg/litre.

Pacemaker lead infection: echocardiographic features, management, and outcome

OBJECTIVE

To compare transthoracic and transoesophageal echocardiography (TTE, TOE) in patients with permanent pacemaker lead infection and to evaluate the safety of medical extraction in cases of large vegetations.

METHODS

TTE and TOE were performed in 23 patients with definite pacemaker lead infection. Seventeen patients without previous infection served as a TOE reference for non-infected leads.

RESULTS

TTE was positive in seven cases (30%) whereas with TOE three different types of vegetations attached to the leads were visualised in 21 of the 23 cases (91%). Of the 20 patients with vegetations and lead culture, 17 (85%) had bacteriologically active infection. Left sided valvar endocarditis was diagnosed in two patients. In the control group, strands were visualised by TOE in five patients, and vegetations in none. Medical extraction of vegetations >/= 10 mm was performed in 12 patients and was successful in nine (75%) without clinical pulmonary embolism. After 31.2 (19.1) months of follow up (mean (SD)), all patients except one were cured of infection; three died from other causes.

CONCLUSIONS

Combined with bacteriological data, vegetations seen on TOE strongly suggest pacemaker lead infection. Normal TTE examinations do not exclude this diagnosis because of its poor sensitivity. Medical extraction of even large vegetations appeared to be safe.

Transatrial lead placement for endocardial pacing in children

Transvenous placement of endocardial leads in children may be difficult due to restrictions and complications of vascular access. We have placed endocardial leads from a transatrial approach in 5 children with various cardiac malformations. The usual surgical approach involved an anterolateral thoracotomy and, under fluoroscopic guidance, passage of the lead tip directly through the right atrial wall and across the tricuspid valve to the apex of the right ventricle. At a mean follow-up time of 23.2 months (range, 12.0 to 27.9 months), all patients have low thresholds for myocardial capture, and there have been no complications. We conclude that placement of endocardial leads by a transatrial approach provides an excellent alternative to an epicardial system in children destined for lifelong pacing.

Usefulness of transesophageal echocardiography for diagnosis of infected transvenous permanent pacemakers

BACKGROUND

Transesophageal echocardiography is superior to transthoracic echocardiography in detecting left-sided valvular vegetations. There are no data on the value of transesophageal echocardiography in the diagnosis of infected transvenous permanent pacemakers.

METHODS AND RESULTS

Transthoracic and transesophageal echocardiography was performed in 10 patients for whom there was clinical suspicion of infected permanent transvenous pacemakers. Transthoracic echocardiography detected pacemaker lead vegetations in 2 patients, whereas transesophageal echocardiography visualized pacemaker lead vegetations in 7 patients. Surgical confirmation was obtained in 6 of these 7 patients. Most patients had more than one pacemaker electrode in place. Local complications at the generator pocket were present in 6 patients. Staphylococcus was the predominant causative organism.

CONCLUSIONS

Transesophageal echocardiography is superior to transthoracic echocardiography in the detection of pacemaker lead vegetations.