Retention of successive position reversals in rats with septal and fronto-polar lesions

Eight successive position reversals were given preoperatively to establish position reversal sets in rats. Six animals received septal lesions, six fronto-polar cortex ablations, and six normals served as a control group. During a series of eight postoperative reversals, rats with septal lesions committed significantly more errors and approach errors than normals while fronto-polar ablations had no detectable effect.     

Temporal-spatial ablation of neural crest in the mouse results in cardiovascular defects.

Neural crest cells are thought to play a critical role in human conotruncal morphogenesis and dysmorphogenesis. Much of our understanding of the contribution of neural crest to cardiovascular patterning comes from ablation and transplantation experiments in avian species. Although fate mapping experiments in mice suggests a conservation of function, the functional requirement for neural crest in cardiovascular development in mammals has not been formally tested. We used a novel two component genetic system for the temporal-spatial ablation of neural crest in the mouse. Affected embryos displayed a spectrum of cardiovascular outflow tract defects and aortic arch patterning abnormalities. We show that the severity of the cardiovascular phenotype is directly related to the level and extent of neural crest ablation. This is the first report of cardiac neural crest ablation in mammals, and it provides important insight into the role of the mammalian neural crest during cardiovascular development.     

经皮腔内室间隔心肌消融术对心电指标的影响

目的研究肥厚梗阻型心肌病患者经皮腔内室间隔心肌消融术对心电指标的影响。方法对50例肥厚梗阻型心肌病患者行经皮腔内室间隔心肌消融术,记录术前、术中和术后出现的心律失常类型,配对分析术前、术后心电指标的变化。结果术后与术前相比,QRS时限[(122.0±24.0)ms对(97.3±15.5)ms,P=0.000]明显延长,QTc[(469.3±32.2)ms对(434.3±41.5)ms,P=0.004]、PR间期[(169±26)ms对(162±24)ms,P=0.044]稍延长。术中心律失常发生率分别为:右束支传导阻滞70%(35/50),左束支传导阻滞8%(4/50),一过性AVB38%(19/50),频发室性早搏24%(12/50),短阵室性心动过速24%(12/50);未发生持续性室性心动过速和室颤。术后心律失常发生率分别为:右束支传导阻滞56%(28/50),左束支传导阻滞8%(4/50),交界区性心动过速4%(2/50),频发室性早搏16%(8/50),短阵室性心动过速8%(4/50)。无永久性起搏器植入及死亡病例。结论经皮腔内室间隔心肌消融术致心律失常的发生率高,右束支传导阻滞最为常见。严格选择适应证后谨慎地行PTSMA术是安全、可行的。     

Pathological Aspects of Radiofrequency Catheter Ablation of the Canine Atrioventricular Node and Bundle of His

Radiofrequency catheter ablation of the atrioventricular (AV) node or bundle of His was performed in 12 adult mongrel dogs. The aim was to create chronic incomplete AV block (first- and second-degree AV block) and to examine the histopathology of the ablated lesions. However, the late electrophysiological results (2 4 weeks follow up) were various: normal in 2 dogs, mild PR prolongation (< 50%) in 2 dogs, first-degree AV block (PR prolongation a 50%) in 2 dogs, second degree AV block in 2 dogs, complete AV block in 4 dogs. The maximally ablated area (%) of the atrioventricular conduction system in serial histologic sections from dogs with these conditions was 69%, 75%, 89.5%, 95% and 99.5%, respectively. The number of intact conduction cells at the maximally ablated site varied from 6 to 30 in the four cases of incomplete AV block. The mean ablated volume (%) of either the AV node or penetrating His bundle correlated roughly with the degree of AV block. The ablated lesions were well demarcated and almost replaced by dense fibrous tissue at 4 weeks. Interruption (3 dogs) or thinning (1 dog) of the endocardial elastic lamellae was detected, in association with endocardial thickening (mean 913 μm). Endocardial thrombi were found in 3 dogs (2 fresh, 1 organized). We conclude that radiofrequency catheter ablation does not cause severe complicated lesions. Several possible conditions for creating chronic incomplete AV block are discussed. Acta Pathol Jpn 41: 487–498, 1991.     

An Investigation into the Electrical Ablation Technique and a Method of Electrode Assessment

Ablative techniques, using standard defibrillators and commonly available cardiac catheters, have been applied to the His bundle and bypass tracts for the management of arrhythmias. We have done in vitro studies of the physical effects of these high energy electrical impulses delivered via different pacing electrodes. Unipolar impulses of 10 to 400 joules were delivered via three U.S.C.I. bipolar electrodes and three Vitatron Helifix electrodes immersed in Ringer's solution. The effects were recorded on 35 mm still film, video tape, and high speed cine film. Pressure, voltage, and current were measured. The U.S.C.I. bipolar electrodes and the Vitatron Helifix electrodes safely withstood repeated delivery of 400-joule impulses which produced similar flash shapes. Each took the form of an incandescent, spherical "fire-ball" centered around the exposed electrode surface. The mean diameters of the "fire-ball" for 10 to 400 J using the U.S.C.I. electrodes were 5-24 mm and 3-20 mm for the Helifix catheter electrodes. Peak pressure excursions of over an atmosphere were observed 3 cm from the electrode tips. Higher pressures, lower voltages, and larger currents occurred using the U.S.C.I. pacing lead. The simple, 35 mm time exposure technique showed that at low energies the flashes appeared to emerge in a retrograde manner from the U.S.C.I. catheters and more distally from the Helifix electrode. This suggested that the latter might be more effective with lower energy impulses. It is concluded that lower energies should be used to take full advantage of the active fixation electrode.     

基于CT的三维数字化导航技术在肺癌介入微波消融治疗中的应用价值

目的 在肺癌微波消融治疗中探究基于CT的三维数字化导航技术的应用价值。方法 回顾性分析我院收治的92例肺癌患者,随机进行三维数字化导航微波消融或传统CT引导下微波消融,分为三维导航组和传统组,依据肿瘤位置、大小（最大径差值≤2 mm）及微波消融条件不同两两配对,共46对,比较2组手术时间、微波针穿刺次数、CT剂量指数、术中并发症发生率、术后病灶控制情况。结果 三维导航组与传统组的手术时间分别为（30.07 ± 6.36）min、（47.20 ± 9.65）min、穿刺次数分别为（1.72 ± 0.69）次、（7.13 ± 3.00）次、CT剂量指数分别为（11.16 ± 2.20）mGy、（26.67 ± 8.72）mGy、术中并发症发生率分别为10.87%、34.78%,以上3个指标三维导航组均低于传统组,三维导航组治疗有效率（93.48%）高于传统组（71.74%）,差异均有统计学意义（P < 0.05）。结论 CT引导下利用三维数字化导航技术行肺癌微波消融治疗,使介入穿刺手术的操作更加精准安全。     

双绒毛膜三羊膜囊三胎妊娠射频消融减胎病例临床结局分析

目的探讨射频消融术(radiofrequency ablation,RFA)对双绒毛膜三羊膜囊(dichorionic triamniotic,DCTA)三胎选择性减胎的安全性以及影响妊娠结局的因素。方法采用回顾性队列研究方法收集2016年1月1日至2020年1月1日期间在南方科技大学第一附属医院深圳市人民医院产科因DCTA三胎要求RFA选择性减胎病例的患者资料,对手术经过、临床结局和并发症,以及其分娩胎盘进行分析。结果共有12例DCTA病例纳入本回顾性分析,RFA手术时孕周为(15.6±1.3)周,分娩孕周为(36.9±1.1)周(34+4~38+2周)。12例中8例接受介入性产前诊断,与未接受介入性产前诊断的病例相比,两组从RFA手术到分娩的间隔差异以及分娩孕周差异均无统计学意义(P>0.05)。共分娩新生儿23例,6例(26%)小于胎龄儿。无论是独立绒毛膜单胎还是单绒毛膜双羊膜囊(monochorionic diamniotic,MCDA)保留胎,出生体质量的平均百分位数明显低于单胎妊娠胎儿体质量的第50百分位数(P<0.001)。1例DCTA中的MCDA保留胎RFA术后4 h死亡(8.3%),死前保留胎一度出现胎儿心动过速伴胎动消失,分娩后胎盘检查显示MCDA保留胎侧胎盘苍白而减灭胎侧胎盘瘀血。收集10例DCTA中MCDA保留胎存活的胎盘,9例可见保留胎胎盘循环通过双胎之间血管吻合支不同程度灌注了减灭胎部分胎盘小叶,1例无明显灌注减灭胎胎盘的病例MCDA保留胎体质量百分位数最低。结论RFA减胎对于DCTA三胎减胎安全有效,减胎后进行介入性产前诊断手术不影响RFA术后继续妊娠时间,术中监测MCDA保留胎心率和胎动异常与不良结局有关,胎盘检查有助于了解不良结局原因,保留胎生长潜能或许与双胎之间的血管吻合类型有关。     

经尿道前列腺气化术治疗前列腺增生症（附60例报道）

目的：观察经尿道气化术治疗前列腺增生症（BPH）的近期疗效。方法：应用经尿道前列腺气化术治疗BPH60例。结果：60例患手术均成功。手术时间20－＃120min。术中心电图、血压无改变。结论：认为经尿道前列腺气化术（TUVP）损伤小、安全性高、疗效确切且并发症少,尤其适用于有严重并发症的高危患,TUVP治疗BPH近期效果好,其远期效果有待进一步随访观察。     

房室结慢径路消融——有效放电过程的心电监测

【目的】探讨房室结慢径路消融有效放电过程心电监测的意义。【方法】58例慢-快型房室结折返性心动过速在有效靶点以低射频能量(15～25W)放电,监测心电变化,出现①交界区心律>150min     

多电极射频肿瘤治疗的体外实验研究

目的　了解射频消融灶大小与功率及时间的关系、超声与大体病理测值的关系、消融灶与周围组织的关系。方法　新鲜牛肝 3只和牛肾 2只 ,消融灶分两组 :距肝表面 1cm和 4cm ;同时将肾脏置于肝表面 ,用不同的功率和时间实验。结果　 10min时 ,2 0W ,40W ,6 0W ,80W的消融灶病理测值分别为 4.1cm ,3.8cm ,3.0cm ,3.3cm ,超声测值分别为 4.5cm ,4.0cm ,4.5cm ,4.0cm。 2 0min时 ,消融灶病理测值分别为 3.0cm ,4.1cm ,2 .8cm ,3.5cm ,超声测值分别为 4.3cm ,4.2cm ,3.4cm ,3.8cm。 30min时 ,消融灶病理测值分别为 3.5cm ,2 .9cm ,3.5cm ,3.4cm ,超声测值分别为 4.5cm ,4.0cm ,3.6cm ,4.1cm。超声和大体解剖测值相比 ,P <0 .0 1。消融灶和周围组织间有0 .3～ 0 .5cm的浅红色移行区。结论　射频消融灶的大小不随功率和时间的增加而增加 ,超声比大体病理测值大 ,两者差别有极显著性意义。消融病灶和周围组织间有移行区。浅表面的消融病灶对临近组织有损伤作用