Cardiac Pacemaker Devices Research Articles

The Composition and Structure of Biofilms Developed by Propionibacterium acnes Isolated from Cardiac Pacemaker Devices.

The present study aimed to understand the biofilm formation mechanism of Propionibacterium acnes by analyzing the components and structure of the biofilms. P. acnes strains were isolated from the surface of explanted cardiac pacemaker devices that exhibited no clinical signs of infection. Culture tests using a simple stamp culture method (pressing pacemakers against the surface of agar plates) revealed frequent P. acnes colonization on the surface of cardiac pacemaker devices. P. acnes was isolated from 7/31 devices, and the isolates were categorized by multilocus sequence typing into five different sequence types (STs): ST4 (JK18.2), ST53 (JK17.1), ST69 (JK12.2 and JK13.1), ST124 (JK5.3), ST125 (JK6.2), and unknown ST (JK19.3). An in vitro biofilm formation assay using microtiter plates demonstrated that 5/7 isolates formed biofilms. Inhibitory effects of DNase I and proteinase K on biofilm formation varied among isolates. In contrast, dispersin B showed no inhibitory activity against all isolates. Three-dimensional live/dead imaging of P. acnes biofilms with different biochemical properties using confocal laser microscopy demonstrated different distributions and proportions of living and dead cells. Additionally, it was suggested that extracellular DNA (eDNA) plays a role in the formation of biofilms containing living cells. Ultrastructural analysis of P. acnes biofilms using a transmission electron microscope and atmospheric scanning electron microscope revealed leakage of cytoplasmic components along with cell lysis and fibrous structures of eDNA connecting cells. In conclusion, the biochemical properties and structures of the biofilms differed among P. acnes isolates. These findings may provide clues for establishing countermeasures against biofilm-associated infection by P. acnes.

Pacemaker site infection caused by Rapidly Growing Nontuberculous Mycobacteria (RGM)

There has been an increased use of cardiac pacemaker device utilization in cardiac patients with a corresponding increase of device-related infections in these patients. The common cause of postpacemaker implantation infection is either Gram-positive or Gram-negative bacteria. Infection of pacemaker implantation site due to nontuberculous mycobacteria is rare. Globally, thirty-two cases of pacemaker device infections caused by nontuberculous mycobacteria were reported. It is important to carry out not only species identification of mycobacteria but also drug susceptibility testing to start precise treatment to those patients, who are infected with atypical mycobacteria. We report a patient with pacemaker pocket infection due to Mycobacterium chelonae.

Improved quality of life after treatment of prolonged asystole during breath holding spells with a cardiac pacemaker.

Objectives:To validate the physical and psychological effectiveness of cardiac pacing in pediatric patients with breath-holding spells (BHS) and prolonged asystole.Materials and Methods:The records and clinical data of all the patients with BHS who presented to our center in the period of 2001–2013 were reviewed. All patients who received cardiac pacemaker implantation for prolonged asystole during BHS were included. In addition, the parents were asked to fill out a standardized quality of life (QOL) questionnaire.Results:Seven patients were identified. The mean onset of symptoms was 7 month (1–12 months) of age, documented asystole was 12–21 seconds, and a permanent cardiac pacemaker device was implanted at a mean age of 23 months (8 months–3.9 years). No pacemaker related adverse events were recorded. Follow up showed immediate resolution from spells in four cases (4/7). Two patients (2/7) showed significant reduction of frequency and severity of spells, with complete elimination of loss of consciousness (LOC). One patient (1/7) with an additional neurologic disorder continued to have minor pallid BHS and eventually switched from pallid to cyanotic spells without further detection of bradycardia or asystole in holter examination. QOL questionnaire revealed significant reduction in subjective stress levels of patients (P = 0.012) and parents (P = 0.007) after pacemaker implantation.Conclusion:Cardiac pacing using appropriate pacemaker settings seems effective in the prevention of LOC and reduction of the frequency of BHS. Our results imply a reduction of subjective stress levels of patients and parents as well as an increased quality of everyday life. After all, randomized controlled trials of the influence of cardiac pacemaker implantation on subjective stress levels in patients with BHS are needed.

Radiation Therapy with Implanted Cardiac Pacemaker Devices: a Clinical and Dosimetric Analysis of Patients and Proposed Precautions

Aims To report the radiation planning dosimetric aspects and clinical outcomes of patients with implanted cardiac pacemakers. Materials and methods Between 2005 and 2009, eight patients with in situ cardiac pacemakers of varied primary site were treated at our hospital. All patients underwent computed tomography-based treatment planning. The target volumes, organs at risk and pacemaker device were all contoured. A treatment plan optimally covering the target area and maximally sparing the pacemaker was generated. All patients were evaluated at baseline, during radiotherapy and after radiotherapy conclusion by a cardiologist as well as pacemaker company personnel. Results The median age at presentation was 67 (range 53–77) years. There were three men with head and neck primaries, two men with lung primaries and three women with breast primaries. The prescribed dose ranged from 45 to 70 Gy in 25–35 fractions with a daily dose of 1.8–2.0 Gy. Four patients had the pacemaker implanted on the same side as the radiotherapy target. The dose ranges for the minimum, mean and maximum doses to the pacemaker were 0.06–2.0, 0.07–20.6 and 0.14–60.0 Gy, respectively. Radiation therapy was safely delivered in all patients without any untoward effects. At 5 months of median follow-up, all patients were well with no malfunction of the pacemaker. Conclusion A series of eight patients with in situ pacemakers treated with radiotherapy is reported. Radiotherapy can be safely delivered in patients with implanted cardiac pacemakers. However, it mandates a cautious approach in planning and treatment delivery to ensure the least possible dose to the pacemaker. Close liaison with the cardiologist and a pacemaker clinic before, during and after the course of treatment is essential to ensure patient safety.

Recipients' of implanted cardioverter‐defibrillators actual and perceived adaptation: a review of the literature

To identify qualitative studies that have examined actual and perceived adaptation of patients to an implanted cardioverter-defibrillator (ICD). The question explored was do recipients of ICDs experience real or perceived physical or psychological adaptation distress? Do themes expressed indicate a need for intervention that will facilitate postimplantation adjustment? A systematic search of the scientific literature uncovered 153 studies of which 12 met the following inclusion criteria: qualitative English research of psychological adaptation to the implantable defibrillator or qualitative research literature reviews. Exclusion criteria included unpublished studies, studies involving cardiac pacemaker devices without defibrillator, and quantitative research studies. Multiple themes pertaining to adjustment to ICD therapy were identified, which warrants further study for potential therapeutic interventions. Themes identified by ICD recipients and their partners include perception of fear, anxiety, and dependence, and the desire for enhanced support and information. Increasing awareness of the complex adaptation issues related to ICD implantation should be a priority of primary care clinicians who provide follow-up care for these patients. ICD recipients have reported multiple physical and psychological adjustment issues that require further study to determine gravity and duration. Clinicians must be familiar with adjustment difficulty expressed by ICD recipients in order to facilitate appropriate tailored interventions. The findings of this literature review emphasize a need for support groups for ICD recipients and their partners; behavioral and sexual counseling; continued education after discharge; and a supportive healthcare provider who is knowledgeable in device adjustment issues. The research indicates a need for a post-ICD implantation plan, and data are available for the design testing of tailored interventions.

Perioperative outcome of pacemaker patients undergoing non-cardiac surgery

Perioperative outcome of pacemaker patients undergoing non-cardiac surgery