[Secondary infections after pacemaker implantation]

Septic Pulmonary Embolism Caused by Infected Pacemaker Leads After Replacement of a Cardiac Resynchronization Therapy Device

BACKGROUND Cardiac resynchronization therapy (CRT) has been demonstrated to reduce morbidity and mortality in patients with advanced, drug-refractory heart failure. Procedure-related mortality is less than 1% in larger studies. Approximately10% of CRT patients have to undergo surgical revision because of infections, dislocations, or unacceptable electrical behavior manifested as high threshold, unstable sensing, or unwanted phrenic nerve stimulation. CASE REPORT A 70-year-old man with symptomatic congestive heart failure underwent implantation of a biventricular pacemaker on the left anterior chest wall in 2003 and pulse generator exchange in August 2009. The patient responded well to CRT. At follow-up, the pacing system functioned normally. In September 2009, in the context of a predialysis program, an abdominal computed tomography (CT) scan was performed in another hospital for assessment and evaluation of chronic kidney disease. This procedure was complicated with peripheral thrombophlebitis that was managed appropriately with complete recovery. Eight months later (May 2010), the patient was admitted to our hospital with fever, anemia, and elevated infection parameters. During admission, blood cultures grew Staphylococcus epidermidis. The chest X-ray, lung perfusion scintigraphy, and CT scan depicted pulmonary embolism and infarction. The right ventricular lead threshold was found to be increased to 7 volts with unsuccessful capture. Echocardiography demonstrated vegetations on leads. The entire pacing system was explanted, but the patient expired few days later following percutaneous removal due to multiorgan failure. CONCLUSIONS In heart failure, replacement of the CRT device may be complicated by bacterial endocarditis. As noted from this case report, sudden elevation of the pacing lead threshold should prompt thorough and immediate investigation to unravel its causes, not only the electrical characteristics but also the anatomical features.

Successful management of multiple permanent pacemaker complications--infection, 13 year old silent lead perforation and exteriorisation following failed percutaneous extraction, superior vena cava obstruction, tricuspid valve endocarditis, pulmonary embolism and prosthetic tricuspid valve thrombosis

A 59 year old man underwent mechanical tricuspid valve replacement and removal of pacemaker generator along with 4 pacemaker leads for pacemaker endocarditis and superior vena cava obstruction after an earlier percutaneous extraction had to be abandoned, 13 years ago, due to cardiac arrest, accompanied by silent, unsuspected right atrial perforation and exteriorisation of lead. Postoperative course was complicated by tricuspid valve thrombosis and secondary pulmonary embolism requiring TPA thrombolysis which was instantly successful. A review of literature of pacemaker endocarditis and tricuspid thrombosis along with the relevant management strategies is presented. We believe this case report is unusual on account of non operative management of right atrial lead perforation following an unsuccessful attempt at percutaneous removal of right sided infected pacemaker leads and the incidental discovery of the perforated lead 13 years later at sternotomy, presentation of pacemaker endocarditis with a massive load of vegetations along the entire pacemaker lead tract in superior vena cava, right atrial endocardium, tricuspid valve and right ventricular endocardium, leading to a functional and structural SVC obstruction, requirement of an unusually large dose of warfarin postoperatively occasioned, in all probability, by antibiotic drug interactions, presentation of tricuspid prosthetic valve thrombosis uniquely as vasovagal syncope and isolated hypoxia and near instantaneous resolution of tricuspid prosthetic valve thrombosis with Alteplase thrombolysis.

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.

Postmortem in situ diagnosis of pacemakers and electrodes to detect dysfunction

Cardiac pacemakers usually are very reliable, but sometimes malfunctions of the system occur. We conceived and developed a method to judge the functionality of pacemaker systems in deceased patients. The idea was to verify the hypothesis that more dysfunctions of implanted pacemaker systems go undetected than are detected and corrected. With the aid of a pre-amplifier and a digital storage oscilloscope, pacemaker pulse signals are derived from the surface of the thorax. The derived pulse shape offers information on the functionality of pacemakers and electrodes. Additionally the lead impedance is measured with a test pacemaker and its corresponding hand-held programmer. Synchronization properties can also be assessed with an external test pacemaker. So far 262 pacemakers have been investigated yielding an anomaly rate of 15%, comprising life threatening to annoying malfunctions. These results emphasize the forensic relevance and give reason for a discussion about the natural cause of death in these cases.

Pacemaker related endocarditis: analysis of seven cases

Vegetative electrode infection following permanent pacemaker implantation is a rare and serious complication. Among 1920 patients who underwent permanent pacemaker implantation in our institute between 1980 and 2000, 7 patients aged 65 to 78 years were diagnosed to have pacemaker related endocarditis. In this study, the clinical course and management strategies for these patients are reviewed. The most frequently encountered factors contributing to development of pacemaker infection were local complications such as postoperative hematoma and inflammation, and recurrent surgical interventions on the pacemaker system. In blood cultures S. aureus was the most common causative microorganism. Echocardiography could be performed in 5 patients. Three patients were referred to open-heart surgery for total removal of the pacemaker system, and one patient had his pacemaker system removed percutaneously. The remaining 3 patients did not agree to either surgical or percutaneous removal. These patients have been under antibiotic therapy for approximately 3 years and they still do not have any signs of a serious infection. Consequently, in patients with permanent pacemakers, infective endocarditis should be considered in the presence of fever and local symptoms. Blood cultures should be obtained and echocardiography should be performed. Complete removal of the pacemaker system with intensive antibiotic treatment is necessary for complete eradication of the infection. However, if percutaneous or surgical removal of the electrodes cannot be done because of high perioperative risk or the patient does not agree to undergo either method, medical treatment with long term antibiotic use may be considered as an alternative.