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经食管电生理检查中的裂隙现象 总被引:1,自引:0,他引:1
在165例食管电生理检查中发现39例患者存在心脏传导系统多部位的裂隙现象共46例次(占24%),其中7例同时发生在2个部位.根据发生部位的不同试将其分成6型,探讨其发生部位及产生机理. 相似文献
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经食管心房起搏研究功能性右束支阻滞 总被引:1,自引:0,他引:1
经食管心房起搏检出101例功能性右束支阻滞。右束支阻滞的早期表现为SV1变浅,右束支阻滞由不完全性到完全性在V1导联演变规律为rS-rs-rR或rS-rs-rsr‘-rsR’。功能性右束支阻滞组的房室交接区功能不应各短于右束支有效不应期,而心房有效不应期不应期与房室交接区有效不应期则显著短于对照组。 相似文献
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分层阻滞与交替下传的文氏现象 总被引:4,自引:2,他引:2
交替下传的文氏现象为Lewis于1912年首先报道,1972年Halpem正式为之命名,其实质是房室交界区的分层阻滞,其与高度房室阻滞易于混淆。 相似文献
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患者男性,20岁.临床诊断:先天性肺动脉口狭窄.心电图V_1导联(图1)示:P波消失,代之以规则的F波,F-F间期0.18s,F-R间期0.20s.R-R间期呈0.56s与0.40s长短交替,长R-R间期后的QRS波群呈 R型,时间0.08s,Rv_11.4mV;短R-R间期后的QRS波群呈宽、窄交替,宽QRS波群呈完全性右束支传导阻滞图形,窄QRS波群形态与长R-R间期后的QRS波群基本一致.心电图诊断:心房扑动伴房室交接区B型交替文氏现象,伴不同程度的心室内差异性传导,右心室肥大. 相似文献
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Medicine has many great pioneers, and in 1899, one such pioneer - Karel Frederik Wenckebach made a discovery which, even to this day, remains one of the fundamental concepts within electrophysiology.Since the Wenckebach Phenomenon was first described, the field of electrophysiology has developed at a rapid pace, allowing us to observe this behaviour, and its complexities, in many new ways. In a similar way, this chapter will illustrate Wenckebach behaviour across a spectrum of modalities from the 12 lead ECG, through to the intra-cardiac recordings from both electrophysiological studies and implantable cardiac devices. In doing so, we continue to shed light on the phe-nomenon first identified through Wenckebach’s meticulous attention to detail some 120 years ago. 相似文献
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Summary We were able to simulate the Wenckebach phenomenon using a model of a one-dimensional cable, consisting of 20 serially connected
Purkinje fiber cells represented by the model of McAllister, Noble, and Tsien. The internal resistance between the 10th and
11th cells was modified to five times the normal. To reconstruct the action potential, the derivative equation was solved
using a fourth-order Runge-Kutta algorithm. When the first cell of the cable was stimulated, periodically, at an interval
of 610ms, a 9:8 Wenckebach pattern was elicited in the conduction between the tenth and 11th cells. Lower order 5:4, 4:3,
3:2 Wenckebach patterns were observed at pacing cycle length of 605, 600—595, and 590—575 ms, respectively. At a pacing cycle
length of 570ms or less, 2:1 block was elicited. In another simulation, only whenI
Na was 0 could the Wenckebach phenomenon be elicited in a cable model, in which internal cell resistance and membrane capacitance
were uniformly set, but in which theI
Na of the center two cells of the cable were alternated between 1 and 0. A localized increase in internal resistance, a relatively
long time constant of deactivation of the delayed rectifier outward current, and a relatively rapid rate of pacing cycle length
was necessary to evoke the Wenckebach phenomenon. The conductance of the delayed rectifier current at the end of an action
potential increased progressively, except after a dropped beat when it was allowed to decrease. It was concluded that the
change of conductance affected the cable property of the fiber and consequently evoked the Wenckebach phenomenon. 相似文献
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S. Serge Barold Roland X. Stroobandt Alfons F. Sinnaeve E. Andries Bengt Herweg 《Annals of noninvasive electrocardiology》2012,17(1):3-7
Understanding of the traditional Wenckebach phenomenon is enhanced by using a modified ladder diagram where AV conduction in any cycle is represented by a slanted line in the AV bar together with similar AV conduction lines of all the preceding cycles. The diagram facilitates calculation of the duration of RR intervals (equal to the basic PP or sinus interval minus the PR or AV increment applied to this particular cycle) and the duration of the pause (equal to 2 × PP or sinus interval minus the sum of all the increments applied to the AV delay). The modified Wenckebach diagram should help students understand the mysterious clustering of QRS complexes or “paradoxical” increase of the ventricular rate that occurs during a Wenckebach sequence. Ann Noninvasive Electrocardiol 2012;17(1):3–7 相似文献
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食管导电球囊电极导管的研制与应用 总被引:2,自引:1,他引:2
郑方胜 《中国心脏起搏与心电生理杂志》2003,17(4):300-302
因普通金属环电极在食管内较难定位心室部位 ,而且起搏阈值高 ,检查时病人痛苦较大 ,限制了经食管心室起搏的临床应用。为探讨一种低阈值、简单易行的经食管心室起搏方法 ,笔者自行设计研制了一种经食管心室起搏导电球囊电极导管。该导电球囊电极经抽、充气可使球囊瘪缩或膨胀 ,以利于球囊导管自鼻孔插入或拔出。导电球囊经充气后膨胀 ,其导电面积较金属环电极增大 5 0倍 ,这有利于降低起搏阈值。笔者对 5 8例受检者同时应用普通金属环电极导管与导电球囊电极导管进行经食管心室起搏。结果 :应用金属环电极导管只有 41例完成检查 ,而导电球囊电极导管有 5 6例顺利完成经食管心室起搏检查 ,其成功率分别为 68.3%与 96.5 % ,心室起搏阈值分别为 38.67± 1 .2 8V和 2 5 .2 7± 3.69V ;两者相比 ,差异有显著性 (P均 <0 .0 5 )。结论 :该导电球囊具有导电面积大 ,与食管接触良好 ,易于在食管内定位起搏心室。与普通金属环电极导管比较 ,具有起搏阈值低、成功率高 ,病人痛苦小等优点 ,值得临床推广应用 相似文献
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经食管心房起搏对功能性左束支阻滞的研究 总被引:5,自引:0,他引:5
研究V1导联左束支阻滞QRS波形的早期表现 ,以及左束支阻滞从不完全性到完全性在V1导联QRS波形的演变规律和影响功能性左束支阻滞显现的因素。 10 0例经食管心房程序刺激显现的具有直接显示性左束支文氏阻滞特征的功能性左束支阻滞病人与 10 0例无功能性束支阻滞的正常者作对比研究。结果 :①功能性左束支阻滞的检出率为 6 .73% ;②V1导联左束支阻滞的早期QRS波形的表现为SV1增深。左束支阻滞从不完全性到完全性在V1导联QRS波形的演变规律为正常rS—深S波的rS—窄QS—宽QS ;③功能性左束支阻滞的房室交界区功能不应期略短于左束支有效不应期 ,而房室交界区相对不应期、功能不应期则显著短于对照组 (5 4 2± 95msvs 5 74±6 4 .1ms,4 15± 5 1.4msvs 4 4 1± 5 1.7ms ,P <0 .0 1)。结论 :左束支阻滞从不完全性到完全性在V1导联上可呈现其演变规律。 相似文献
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Heart failure affects nearly 6 million Americans, with a half-million new cases emerging each year. Whereas up to 50% of heart failure patients die of arrhythmia, the diverse mechanisms underlying heart failure-associated arrhythmia are poorly understood. As a consequence, effectiveness of antiarrhythmic pharmacotherapy remains elusive. Here, we review recent advances in our understanding of heart failure-associated molecular events impacting the electrical function of the myocardium. We approach this from an anatomical standpoint, summarizing recent insights gleaned from pre-clinical models and discussing their relevance to human heart failure. 相似文献
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心房颤动患者心房电生理特性的研究 总被引:1,自引:0,他引:1
目的 观察心房颤动 (房颤 )患者的心房传导性及心房不应期 ,探讨房颤发生机制。方法 以既往无房颤病史、在心脏电生理检查中出现房颤的 72例非器质性心脏病患者作为研究对象 ,测量反映心房传导的电生理参数 (P A、P CSd、S1 A1、最大S2 A2、MaxCD、CDzone)及心房有效不应期(ERPHRA) ,与同等条件下无房颤发作的患者进行比较。结果 房颤组P A、P CSd、最大S2 A2、MaxCD、CDzone显著延长 (P =0 0 0 1) ,ERPHRA 明显缩短 (P =0 0 0 1)。结论 心房传导性的降低和心房有效不应期的缩短是房颤发生的心房电生理基础 相似文献
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了解非器质性心脏病的患者在作食管电生理检查时裂隙现象发生的情况及类型 ,并观察药物及不同刺激方式对裂隙现象的影响。对在我院作食管电生理检查的 2 2 0例患者 ,先采用S1S2 法 ,每次递减 10ms进行反扫 ,直至S1S2 间期小于 2 0 0ms ,并且连续 3次以上的早搏刺激无下传 ;其中 6 2例患者同时作了S1S2 与S1S2 S3 法检查 ,2 6例用异丙肾上腺素前后行早搏刺激 ,观察裂隙现象的发生情况。 2 2 0例患者中 6 9例患者出现裂隙现象 ,总共 83例次 ,8例有双裂隙 ,裂隙带时限 45 .3± 32 .1(10~ 12 0 )ms;裂隙类型有房室结及结下组织形成的裂隙 42例次、房室结与束支形成的裂隙 2 8例次、束支裂隙 11例次、旁道裂隙 2例 ;房室结双径路的裂隙现象发生率高于其他患者 ;S1S2 法的裂隙现象发生率高于S1S2 S3 法 ;用异丙肾上腺素后的裂隙现象发生率高于用药前。裂隙现象是无器质性心脏病的患者作食管电生理检查时常见的电生理现象 ,它的发生与激动传导径路、早搏刺激的方式和用药有关。 相似文献
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短时间快速右心房起搏致犬心房电重构、收缩重构及解剖重构的实验研究 总被引:2,自引:0,他引:2
目的通过对快速心房起搏犬的电生理特性、收缩功能及超微结构的研究,观察短时间快速心房电活动是否可引起心房重构,并探讨其在房颤持续中的作用。方法健康杂种犬17只。实验组12只,经右心耳起搏450次/min,持续5小时。快速心房刺激前后分别测量P波时程及心房有效不应期,并用多普勒超声评价二尖瓣前向血流变化。实验结束后取左心耳及梳状肌组织观察其超微结构。对照组5只,插入电极但不起搏,与实验组同步行各项检查。结果持续快速刺激5小时后,实验组心房有效不应期降低,P波时程增加;二尖瓣心房收缩期血流速度降低了17%;检查发现部分心肌细胞出现肌原纤维的损失、糖原累积及线粒体大小及形状的改变;而对照组均未发现明显变化。结论短时间快速心房电活动可导致犬心房发生电重构、收缩重构及结构重构,而心房结构重构可能是心房发生电重构和收缩重构的原因之一。 相似文献