41 research outputs found

    Preventing Phrenic Nerve Stimulation by a Patch Insulation in an Intact Swine Heart Model

    No full text
    <div><p>Introduction</p><p>Phrenic nerve stimulation (PNS) could be prevented by a silastic patch over the epicardial lead. We studied the effects in preventing PNS by placing a silastic patch directly over an epicardial lead or placing a graft around the phrenic nerve (PN).</p><p>Methods and Results</p><p>Fourteen Lanyu swine were enrolled. A bipolar lead was placed epicardially on the left ventricle (LV) inferior to the PN. An implantable cardioverter-defibrillator (ICD) lead was placed into the right ventricle (RV). The maximal influential distance (MID) was measured under 3 pacing configurations to express the influential electrical field on the PN. The threshold of the LV and PN were evaluated epicardially. Then, PTFE patches of different sizes (10×10 mm, 20×20 mm and 30×30 mm) were placed between the LV lead and PN to study the rise in PN threshold in 7 swine. On the other hand, the PN were surrounded by a PTFE graft of different lengths (10 mm, 20 mm, and 30 mm) in the remaining 7 swine. LV-bipolar pacing showed the shortest MID when compared to the other 2 unipolar pacing configurations at pacing voltage of 10 V. The patch was most effective in preventing PNS during LV-bipolar pacing. PNS was prevented under all circumstances with a larger PTFE patch (30×30 mm) or long graft (30 mm).</p><p>Conclusions</p><p>PNS was avoided by placing a PTFE patch over the LV lead or a graft around the PN despite pacing configurations. Hence if PNS persisted during CRT implantation, a PTFE patch on the LV lead or a graft around the PN could be considered.</p></div

    The strength–duration curves with the LV-tip to RV-coil (panel A), LV-tip to RV-ring (panel B), and LV-bipolar (panel C) pacing configurations.

    No full text
    <p>The strength–duration curve of the LV had a steeper slope than that of the PN. * = <i>p</i><0.05 indicated comparisons between the thresholds of myocardium and PN in the same pulse width.</p

    The MID was shortest during LV-bipolar pacing.

    No full text
    <p>Unipolar pacing configuration by the LV-tip to RV-ring had the shorter MID than the LV-tip to RV-coil pacing configuration when the pacing voltage over 5 V. <b>*</b> = <i>p</i><0.05 indicated comparisons among the 3 groups (LV-tip to RV-coil vs. LV-tip to RV-ring vs. LV-bipolar), <b>#</b> = <i>p</i><0.05 indicated comparisons between the 2 unipolar pacings (LV-tip to RV-coil vs. LV-tip to RV-ring).</p

    Preventing Phrenic Nerve Stimulation by a Patch Insulation in an Intact Swine Heart Model - Figure 1

    No full text
    <p>Panel A: A commercially available 1.1 mm tip-to-ring spaced LV pacing lead was inserted through a small hole created in the pericardium. The tip electrode position was maintained along the course of the left PN as the cathode, and the position was maintained inferior to the PN in order to keep homogeneous pacing conditions. An ICD lead with a single coil was then inserted into the RV using its ring or coil as the anode. The LV lead position was adjusted to measure the MID. Panel B: A PTEF patch was placed between the LV lead and the PN. Panel C: The PN was isolated from the pericardium and then a PTFE graft was placed around the PN. The black dotted line indicates the suture line. (Panel D).</p

    ROC curve for the ADMA levels in predicting adverse events.

    No full text
    <p>The area under the curve for ADMA levels in predicting adverse events was 0.767 (95% confidence interval  =  0.654–0.879). ADMA  =  asymmetric dimethylarginine; ROC curve  =  receiver-operator characteristics curve.</p

    ADMA levels in AF and non-AF patients.

    No full text
    <p>The ADMA levels were higher in AF patients compared to non-AF patients. In addition, non-PAF patients had higher levels of ADMA than PAF patients. ADMA  =  asymmetric dimethylarginine; AF  =  atrial fibrillation; PAF  =  paroxysmal atrial fibrillation. *P value <0.05, PAF or non-PAF versus no AF. <sup>+</sup>P value <0.05, Non-PAF versus PAF.</p

    Event-free survival curve for patients with different ADMA levels.

    No full text
    <p>Kaplan-Meier survival analysis showed that the patients with an ADMA level ≥ 0.55 µmol/L were associated with a higher event rate compared to patients with an ADMA level <0.55 µmol/L (33.3% versus 9.3%, p = 0.001). ADMA  =  asymmetric dimethylarginine.</p

    Linear regression models on the relationship between PA-PDI interval and pericardial fat.

    No full text
    <p>hs-CRP = high sensitivity C-reactive protein; LV = left ventricle; LVEF = left ventricular ejection fraction; LVIDD = left ventricular internal dimension at end-diastole; SE = standard error; WBCs = white blood cells.</p
    corecore