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排序方式: 共有477条查询结果,搜索用时 12 毫秒
1.
目的 探讨术中电生理监护对椎管神经鞘瘤显微手术中的作用及意义,提高对椎管内神经鞘瘤的治疗水平。方法 回顾性分析65例术中电生理动态监护下,显微手术切除椎管内神经鞘瘤。结果 治愈60例(占92.3%),好转5例(占7.7%),无死亡;肿瘤全切62例,次全切除3例,全切率95.4%。结论 常规动态电生理监测下显微手术切除椎管神经鞘瘤,能保全脊髓神经的功能,减少副损伤,提高手术安全性;显微手术有助于提高肿瘤全切率,可有效减少术后复发。对影响脊柱稳定性的行脊柱融合内固定。  相似文献   
2.
心房颤动外科手术的发展与评价   总被引:1,自引:0,他引:1  
随着电生理学对房颤机制的深入研究和新型标测技术消融能源的发展,房颤的外科治疗不断取得新的突破.由Cox迷宫手术的复杂术式逐渐向左迷宫、放射迷宫衍变.减少创伤提高治愈率,成为房颤外科治疗不断追求的新目标.本文概述了房颤外科治疗的各种术式设计原理和房颤根治术新消融技术的应用及其疗效评价.  相似文献   
3.
Tedisamil is a new bradycardic agent, previously shown to block transient outward and delayed rectifier potassium currents in cardiac tissue [1,2]. In the present study tedisamil caused bradycardia and Q-Tc widening in rats and primates. Q-Tc widening is indicative of class III antiarrhythmic actions. In keeping with this, tedisamil had antiarrhythmic activity against electrical and ischemia-induced arrhythmias in rats. In rats, 0.5–4 mg/kg IV tedisamil caused parallel and dose-related increases in action-potential duration, Q-Tc interval, and refractory period; and decreases in maximum ventricular following frequency. In primates after 0.5–2.0 mg/kg IV, findings were similar for indices of Q-T widening and decreases in maximum ventricular following frequency. Tedisamil did not change QRS width, nor did it increase threshold currents for capture of ventricles, nor for fibrillo-flutter at doses below 4 mg/kg in rats. These findings were consistent with the lack of significant sodium-channel blockade. However, upon increasing the dose to 4 mg/kg, ventricular fibrillo-flutter could not be induced in rats by electrical stimulation; instead, only ventricular tachycardias with slow rates occurred. Ischemia-induced ventricular fibrillation was reduced in a dose-related manner by tedisamil in rats. The overall incidence of ischemia-induced ventricular tachycardia was not markedly reduced, but rates during tachycardic episodes were lower. When pacing was used to overcome tedisamil-induced bradycardia, antiarrhythmic actions during ischemia were more pronounced. These findings are consistent with the hypothesis that tedisamil increased refractoriness, which resulted in extended path lengths for reentry circuits and slower rates during episodes of ventricular tachycardia. High doses of tedisamil increased path lengths so much that the multiple reentry circuits of fibrillation could no longer occur. The limited study in primates suggests similar mechanisms could occur in humans.  相似文献   
4.
We herein report two P/Q-type voltage-gated calcium channel (VGCC) antibody-positive Lambert-Eaton myasthenic syndrome (LEMS) patients who responded dramatically to cholinesterase inhibitors. Patient 1, a 76-year-old man, had small-cell lung cancer and developed LEMS during chemotherapy. When symptomatic treatment was started with pyridostigmine, gait disturbance was ameliorated, and his modified Rankin scale decreased from 4 points to 3 points. Patient 2, a 68-year-old man, had cancer-free LEMS. Distigmine bromide was very effective and ameliorated not only his gait disturbance but also autonomic symptoms, and his modified Rankin scale decreased from 2 points to 1 point. Cholinesterase inhibitors alone may be effective in a small portion of LEMS patients.  相似文献   
5.
方永辉  施志雄 《广西医学》2004,26(9):1277-1278
目的 研究冠心病患者心室晚电位 (VLP)及心率变异 (HRV)的改变 ,探讨VLP、HRV对冠心病病情预测及心脏事件发生的防治。方法 随机分为冠心病组 73例 ,对照组 6 0例。检测VLP的QRS终未 4 0UV以下振幅的持续时间 (D40 ) ,QRS终未 4 0ms内的均方根电压 (V40 ) ,经滤波后QRS总的持续时间 (QRST)。检测HRV的各种指标 :全程NN间期标准差 (SDNN) ,全程NN间期之差的均方根 (RMSSD) ,NN5 0除以总的NN间期的个数 (PNN5 0 ) ,低频段功率 (LF)与高频段功率 (HF)之比 (LF/HF)。结果 冠心病组VLP阳性率 2 6 0 3% (19/ 73) ,对照组阳性率 6 6 7% (4 / 6 0 )。冠心病组SDNN(99 5 1± 6 5 6 )ms、RMSSD(2 2 4 2±6 5 7)ms,PNN5 0 (5 4 0± 3 0 8) % ,LF/HF(4 38± 3 36 )。对照组SDNN(14 2 76± 79 6 6 )ms,RMSSD(2 7 89± 12 89)ms ,PNN5 0 (9 18±8 5 3) % ,LF/HF(1 5 2± 1 4 9)。经统计学处理两组SDNN、RMSSD、PNN5 0、LF/HF差异均有非常显著性差异 (P <0 0 1)。结论 冠心病组VLP、HRV均有显著性改变 ,提示冠心病患者存在心肌电活动异常及自主神经功能损害 ,存在心脏事件发生的危险性。  相似文献   
6.

Background

Information on young patients with Brugada syndrome (BrS) and arrhythmic events (AEs) is limited.

Objectives

The purpose of this study was to describe their characteristics and management as well as risk factors for AE recurrence.

Methods

A total of 57 patients (age ≤20 years), all with BrS and AEs, were divided into pediatric (age ≤12 years; n = 26) and adolescents (age 13 to 20 years; n = 31).

Results

Patients’ median age at time of first AE was 14 years, with a majority of males (74%), Caucasians (70%), and probands (79%) who presented as aborted cardiac arrest (84%). A significant proportion of patients (28%) exhibited fever-related AE. Family history of sudden cardiac death (SCD), prior syncope, spontaneous type 1 Brugada electrocardiogram (ECG), inducible ventricular fibrillation at electrophysiological study, and SCN5A mutations were present in 26%, 49%, 65%, 28%, and 58% of patients, respectively. The pediatric group differed from the adolescents, with a greater proportion of females, Caucasians, fever-related AEs, and spontaneous type-1 ECG. During follow-up, 68% of pediatric and 64% of adolescents had recurrent AE, with median time of 9.9 and 27.0 months, respectively. Approximately one-third of recurrent AEs occurred on quinidine therapy, and among the pediatric group, 60% of recurrent AEs were fever-related. Risk factors for recurrent AE included sinus node dysfunction, atrial arrhythmias, intraventricular conduction delay, or large S-wave on ECG lead I in the pediatric group and the presence of SCN5A mutation among adolescents.

Conclusions

Young BrS patients with AE represent a very arrhythmogenic group. Current management after first arrhythmia episode is associated with high recurrence rate. Alternative therapies, besides defibrillator implantation, should be considered.  相似文献   
7.
Lipid emulsions are used in the reversal of local anesthetic toxicity. The aim of this study was to investigate the cellular electrophysiological effects of long‐chain triglyceride lipid emulsion (LCTE) on cardiac action potential characteristics and conduction disturbances induced by bupivacaine. Purkinje fibers were dissected from the left ventricle of New Zealand white rabbit hearts and superfused with either Tyrode's solution during 30 min (control group), with bupivacaine 10?6 m , 10?5 m , and 5.10?5 m alone, or in the presence of LCTE 0.5%, in addition, LCTE at 0.1%, 0.5%, and 1% was perfused alone. Electrophysiological parameters were recorded using the conventional microelectrode technique (37 °C, 1 Hz frequency). Bupivacaine 5.10?5 m ‐induced conduction blocks (8/8 preparations): LCTE 0.5% suppressed the bupivacaine 5.10?5 m ‐induced conduction blocks (1/8 preparations). Exposure to bupivacaine 10?6 m , 10?5 m , and 5.10?5 m resulted in a significant decrease in the maximal rate of depolarization (Vmax) (respectively, 25%, 55%, 75%; P < 0.002 vs. control group). In the presence of LCTE 0.5%, bupivacaine 10?6 m did not significantly decreased Vmax (13%; P = 0.10 vs. control group). The decrease in Vmax resulting from bupivacaine 10?5 m alone was significantly less in the presence of LCTE 0.5% (P < 0.01 vs. bupivacaine 10?5 m alone). Exposure to bupivacaine 10?6 m , 10?5 m , and 5.10?5 m alone or in the presence of LCTE 0.5% resulted in a significant decrease in action potential duration measured at 50% and 90% repolarization (APD50 and APD90; P < 0.01 vs. control group). LCTE inhibited the Purkinje fibers conduction blocks induced by bupivacaine. Moreover, LCTE 0.5% attenuates the decrease in Vmax induced by bupivacaine 10?6 m and 10?5 m .  相似文献   
8.
This article describes a 54-year-old man with incessant supraven-tricular tachycardia refractory to antiarrhythmic drugs. Multiple concealed accessory pathways associated with antegrade triple AV nodal pathways were documented by a series of successful catheter ablations and detailed electrophysiological studies. After the left-wall accessory pathways were abolished with two courses of multiple low energy shocks, another two accessory pathways, one near the os of coronary sinus and the other near the site of the His bundle, were documented by programmed premature ventricular stimulation. This was followed by a third course of shocks to the os of coronary sinus for ablating posteroseptal AP and a fourth course of shock to proximal His bundle for control of SVT with a septal accessory pathway as a retrograde limb and AV nodal pathways as an antegrade limb. Without medications, the patient has remained asymptomatic even during moderate physical activity over a follow-up period of 36 months. His ECG showed sinus rhythm with persistence of right bundle branch block.  相似文献   
9.
BACKGROUND: The diagnostic significance of a tilt table test (TTT) in patients with a suspected arrhythmic etiology for syncope and negative electrophysiologic study (EPS) has not been previously assessed comparing the TTT results with the findings of prolonged monitoring using an implantable loop recorder (ILR). We sought to assess the diagnostic yielding of TTT in patients with suspected arrhythmic syncope and negative EPS. METHODS AND RESULTS: In 81 patients with suspected arrhythmic etiology for syncope and negative EPS, TTT was performed and an ILR implanted regardless the results of TTT. TTT was positive in 38 patients. During follow-up, syncope or presyncope recurred in 32 patients (39.5%). No differences were found in recurrence rates in patients with positive and negative TTT (31.5% vs 46.5%, P = ns). According to rhythm registered during ILR activation, mechanisms of syncopal events were classified as: arrhythmic (atrioventricular [AV] block and ventricular tachycardia; n = 18), neurally mediated (sinus bradycardia and sinus pause; n = 9), and indeterminate (normal sinus rhythm; n = 5). There was no statistical association between the results of TTT and the mechanism of syncope. CONCLUSIONS: In patients with a suspected arrhythmic etiology for syncope and a negative EPS, TTT is of little value to predict the mechanism of syncope and the ILR implantation seems to be a useful and safe diagnostic strategy.  相似文献   
10.
王劲风  汪祥海  蔚有权  刘文洁  杨浩 《安徽医药》2015,36(10):1194-1196
目的 探讨Carto 3三维电生理导航系统指导消融频发性室性早搏(PVC)的临床疗效,以及射频消融术(RFCA)前后血浆氨基末端B型利钠肽(NT-pro BNP)、心脏结构功能的变化。方法 选取2011年至2013年47例频发室性早搏患者行射频消融治疗的患者为病例组,根据标测系统的不同,分为传统组(n=17)和三维组(n=30)。观察比较两组手术时间、X线曝光时间、放电次数及手术即刻成功率、远期成功率。同时监测所有病例行导管消融前及消融3个月后的NT-pro BNP、左室射血分数(LVEF)及左室舒张末期内径(LVEDd)值,另选取51例健康体检者为对照组。结果 三维组在手术时间、X线曝光时间、消融放电次数上明显优于传统组,且差异有统计学意义(P<0.05)。两组即刻成功率(82.35% vs 93.33%)、远期成功率(76.47% vs 86.67%)相近,差异无统计学意义(P>0.05)。对照组、病例组术前、病例组术后3个月NT-pro BNP浓度、LVEDd以及LVEF值比较,差异均无统计学意义(P>0.05)。结论 较二维影像,在Carto 3三维电生理导航系统下行射频消融治疗频发性室性早搏具有较高的即刻及远期成功率,且安全、有效。  相似文献   
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