Single-step transvenous extraction of a passive fixation lead with delayed perforation of the right ventricle

Delayed pacemaker lead perforation is a very rare complicationand most of the published reports involve active fixation leads.The authors report an uneventful transvenous extraction of apassive fixation lead, which had a delayed perforation of theright ventricle, disclosed two months after pacemaker implantation.     

Lead and Attention-Deficit/Hyperactivity Disorder (ADHD) symptoms: A meta-analysis

This meta-analysis examined the association between Attention-Deficit/Hyperactivity Disorder (ADHD) symptoms and lead exposure in children and adolescents. Thirty-three studies published between 1972 and 2010 involving 10,232 children and adolescents were included. There was a small to medium association between inattention symptoms and lead exposure (r = .16, k = 27, p < .001) and a similar association between hyperactivity/impulsivity symptoms and lead exposure (r = .13, k = 23, p < .001). There was significant heterogeneity among the effect sizes for both inattention symptoms and for hyperactivity/impulsivity symptoms, with studies using hair analysis to assess lead burden yielding substantially larger effect sizes than those using other methods. Excluding the hair analysis studies, the average rs were .14 for inattention (k = 23, p < .001) and .12 for hyperactivity/impulsivity (k = 21, p < .001). Overall, the relation between lead exposure and ADHD symptoms was similar in magnitude to the relation between lead exposure and decreased IQ and between lead exposure and conduct problems.     

Over the wire lead extraction and focused force venoplasty to regain venous access in a totally occluded subclavian vein

Introduction  Venoplasty allows the addition or replacement of leads despite subtotal or total subclavian occlusion. Methods  The threshold of the LV pacing lead implanted for biventricular pacing over a period of 18 months increased to greater than 5 V. A pre implant venogram revealed total subclavian occlusion. Venous access was maintained by extraction of the 4 F LV lead over a wire. Subsequently the sheath would not advance despite 6mm balloon inflation to 30 atm with no residual waist. A wire was placed beside the balloon and the balloon was reinflated. Results  The subclavian obstruction was eliminated without damage to the existing leads. Conclusion  The obstruction formed by the fibrous track around an extracted lead may persist despite what appears to be successful balloon dilation. Inflation with a wire beside the balloon increases the effect eliminating the resistant obstruction without damaging the leads. Acknowledgements of Sources of Financial Support:Dr. Worley receives compensation in various forms from Medtronic, Pressure Products, Guidant, and St Jude Medical. Dr. Gohn receives compensation in various forms from Medtronic. No financial support was provided for the creation of this case report     

Dysplastic changes in erythroid precursors as a manifestation of lead poisoning: report of a case and review of literature

Dysplastic changes in erythroid precursors occur not only in patients with hematologic diseases, but also those with other diseases. Here, we report on a patient that presented with dysplastic changes in erythroid precursors due to lead poisoning from the intake of Chinese folk remedies.     

探讨铅暴露对女性FSH、PRL、LH等激素水平的影响

目的初步探讨低水平铅暴露对女性血清性激素及月经周期的影响。方法对铅暴露女性269人及对照组女性348人的一般情况、生殖结局进行回顾性队列研究,并测血铅及用放射免疫法测定孕酮（P）、雌二醇（E2）、催乳素（PRL）、卵泡刺激素（FSH）、黄体生成素（LH）性激素水平。结果暴露组女性月经紊乱明显高于对照组（P〈0．01）,且早产率、自然流产率亦高于对照组,差异有统计学意义（P〈0．01）;暴露组血清性激素水平孕酮（P）、雌二醇（E2）降低,促卵泡素、促黄体生成素升高。结论说明长期低浓度铅暴露干扰下丘脑一垂体～卵巢轴正常的内分泌调节功能,可引起女性月经失调、影响内分泌激素水平。     

Effect of lead trajectory on the response of essential head tremor to deep brain stimulation

BackgroundEssential tremor (ET) is one of the most common movement disorders. Normally ET affects the distal upper extremities, but it can also be accompanied by midline symptoms. Ventralis intermedius (VIM) thalamic deep brain stimulation (DBS) has been shown to be effective in reducing hand tremor, but its effects on head tremor have been inconsistent.MethodsTwenty-nine DBS patients with a diagnosis of ET met inclusion criteria. All implantations targeted VIM. The factors examined included age, gender, disease duration, presence or absence of head tremor, handedness, and the Fahn-Tolosa-Marin rating scale (TRS). This analysis specifically focused on TRS head tremor sub-scores at baseline, 6 months and 12 months post-DBS. Additionally, DBS lead entry angles were examined.ResultsTwenty-three ET patients underwent unilateral DBS and six underwent staged bilateral DBS. At both 6 and 12 months following DBS, stimulation resulted in diminished head tremor (ON vs OFF; p < 0.0001). The most important predictor of head tremor suppression was the entry angle of the DBS lead in the sagittal projection relative to the AC–PC axial plane (AC–PC angle). Head tremor reduction was greater among more vertical AC–PC angles.ConclusionA more vertical AC–PC angle of the DBS lead trajectory was associated with improved head tremor suppression. Further studies will be necessary to confirm this potentially important finding.