Inadvertent Detection of 60-Hz Alternating Current by an Implantable Cardioverter Defibrillator

LEE, S.W., et al. : Inadvertent Detection of 60-Hz Alternating Current by an Implantable Cardioverter De-fibrillator. A patient with an ICD received therapies from his ICD while exercising in an indoor swimming pool. Interrogation of the ICD revealed inappropriate detection of 60-Hz alternating current artifact and delivery of ICD therapies.     

Percutaneous Retrieval of Dislodged Left Atrial Appendage Occlusion Devices through the Transseptal Approach

Percutaneous left atrial appendage (LAA) occlusion is a promising treatment option in patients with atrial fibrillation who have a high risk of embolic stroke and are not eligible for chronic oral anticoagulation therapy. This procedure, however, can induce several complications. Device embolization can result in a serious situation, requiring immediate and safe device removal. We report two cases in which dislodged LAA occlusion devices were flitting in the left atrium or entrapped in the mitral valve leaflets and were successfully retrieved through a transseptal approach without complications.     

Dual Sensor VVIR Mode Pacing: Is It Worth It?

Dual sensor ventricular demand rate responsive (VVIR mode) pacing was compared with single sensor rate responsive pacing to assess whether this new development should be more widely incorporated in modern pacemaker devices. A within patient randomized, double-blind crossover study involving ten patients, mean age 67.4 years (70% male), had Medtronic Legend Plus dual sensor VVIR pacemakers implanted for high grade A V block and chronic or persistent paroxysmal atrial fibrillation. Performance values were compared to 20 healthy control subjects of a similar age and gender. Patients were both subjectively and objectively assessed after 2 weeks of out-of-hospital activity in VVIR mode (minute ventilation sensing), VVIR mode (activity sensing), VVIR mode (dual sensor), and VVI mode (no rate response). All patients were assessed for subjective preference for, and objective improvement in, any pacing modality as assessed by standardized daily activity protocols and graded exercise treadmill testing. Subjective perception of exercise capacity and functional status was significantly lower in VVI mode (P < 0.05) compared to any of the VVIR modes, which did not differ. After completion of the study 70% of patients chose VVIR as their preferred mode, with 30% expressing no preference. Forty percent preferred activity sensor WIR mode pacing, 30% preferred dual sensor VVIR mode pacing, and 70% found either dual sensor WIR mode, minute ventilation sensor WIR mode, or both modalities least acceptable. No patient found activity sensing WIR mode least acceptable. Graded treadmill testing revealed significantly lower exercise tolerance during WI mode pacing (P < 0.01) compared to the VVIR modalities, which did not differ. Overall, chronotropic response was best with dual sensor pacing during standardized daily activity protocols and during the standard car journey. The data from this study suggest that there is no marked clinical advantage obtained from the use of dual sensor devices over current activity sensing ventricular demand rate responsive pacemakers, but with the probable added disadvantages of increased size, complexity, cost, and decreased longevity.     

Bilateral Decompression via Microscopic Tubular Crossing Laminotomy (MTCL) for Lumbar Spinal Stenosis: Technique and Early Surgical Result

The purpose of this study was to determine the feasibility and efficacy of bilateral decompression procedure via microscopic tubular crossing laminotomy (MTCL) for treating lumbar spinal stenosis (LSS). Seventeen patients with LSS underwent bilateral decompression via an MTCL procedure in which tubular retractor was placed. The mean age was 72 (range 59–84) years and there were 10 men and 7 women. All patients underwent pre- and postoperative dynamic lumbar x-ray, magnetic resonance (MR) image, and computed tomography. To verify the efficacy of this technique, pre- and postoperative cross-sectional area (CSA) of thecal sac, facet resection, and fatty infiltration (FI) of multifidus were measured. Clinical results were evaluated using Oswestry Disability Index (ODI), back and leg visual analog scale (VAS). The mean follow-up period was 17.5 months (range 12.1–21.2). 70.5% of MTCL was performed at the level of L4–5 and one case of dural violation (5.8%) was noted at the level of L5–S1. The mean preoperative CSA was 70.5 mm² (range 25.1–87.6) and it increased to 198.8 mm² (range 177.3–219.2) postoperatively (p = 0.00). The mean facet resection rate was 18.4% (range 9.9–26.9) and no radiological instability was noted postoperatively. MR image showed no increase in FI of the multifidus after 12 months of follow-up (p = 0.53). Preoperative clinical symptoms improved significantly at postoperative 6 months and 12 months of follow-up. These results indicate that an MTCL with use of tubular retractor system can be an effective procedure to achieve neural decompression for the treatment of LSS and it may be beneficial in preserving both facet joint and multifidus muscle.     

Is There Any Objective Improvement of Nocturia by Combination Treatment of Zolpidem and Alpha‐Blocker Therapy for Unresponsive to Alpha‐Blocker Monotherapy in Men with Lower Urinary Tract Symptoms?

Objectives: The aim of the present study was to determine whether administration of zolpidem, a nonbenzodiazepine sedative‐hypnotic agent, at night would improve the nocturia unresponsive to alpha‐blocker monotherapy in men with lower urinary tract symptoms (LUTS). Methods: This was a prospective observational study comprised of 39 men aged 50 years and older. The study inclusion criteria were age more than 50 years, and nocturia twice or more per night after taking alpha‐blockers for more than 8 weeks. A total of 39 patients met the criteria and constituted the study cohort. Pittsburgh Sleep Quality Index (PSQI), International Prostate Symptom Score (IPSS), frequency volume chart (FVCs) and uroflowmetry were recorded. Patients were given 10 mg alfuzosin and 10 mg zolpidem once at night for the 8 weeks. Results: There were no serious side‐effects in any patient. Nocturia decreased from a baseline (3.1 ± 0.1) to 8 weeks (1.6 ± 0.2) (P = 0.001). After treatment, global PSQI scores and severe sleep disorders improved. Storage and voiding symptoms including total IPSS scores and quality of life index improved. Nocturnal urine volume and functional bladder capacity improved. Maximum flow rate, voided volume increased and residual urine volume decreased. Conclusion: Combined zolpidem and alpha‐blocker therapy resulted in a subjective and objective reduction in nocturia episodes when given to men with nocturia unresponsive to alpha‐blocker monotherapy.     

In vitro metabolism of the new insecticide flupyrazofos by rat liver microsomes

1. The in vitro metabolism of the new insecticide flupyrazofos was studied using rat liver microsomes. Two metabolites were produced and identified as O, O -diethyl O -(1- phenyl-3-trifluoromethyl-5-pyrazoyl) phosphoric acid ester (flupyrazofos oxon) and 1- phenyl-3-trifluoromethyl-5-hydroxypyrazole (PTMHP) based on UV and mass spectral analysis. 2. Cytochrome P450 oxidatively converted flupyrazofos to flupyrazofos oxon, a major metabolite and phenobarbital-induced microsomes increased this desulphuration by 8- fold. 3. Flupyrazofos oxon was converted to PTMHP with a half-life of 47 8?min by chemical hydrolysis and this conversion also proceeded non-enzymatically under our microsomal incubation conditions.