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41.
42.
DOMANOVITS H.; LASKE H.; STARK G.; STERZ F.; SCHMIDINGER H.; SCHREIBER W.; MULLNER M.; LAGGNER A. N. 《European heart journal》1994,15(5):589-593
We developed a new protocol for diagnosis and treatment of patientswith sustained tachycardias (heart rate > 150 beats. min1).The patients first underwent vagal manoeuvres; if those remainedunsuccessful, i.v. adenosine in increasing doses of 6, 12, and18 mg was administered until sinus rhythm (SR) or transientatrioventricular (AV) block, unmasking the underlying rhythm,was recorded. In the latter and in the non-responding casesother antiarrhythmics were applied. Ninety-three episodes of tachycardia in 46 patients were treatedaccording to this protocol. Six episodes (6%) were terminatedby carotid massage, 64 of the remaining 87 episodes (74%) respondedto adenosine with return to SR. Conversion to SR occurred moreoften in episodes with narrow- than in wide-complex tachycardia(81 vs 59%, P<005). To achieve SR, the mean adenosine dosewas lower in narrow- than in wide-complex tachycardia (13±8vs 21 ± 10 mg; P<0.01). The duration of asystole afteradenosine did not differ between these two groups, whereas theduration of arrhythmia after adenosine differed significantly(8.5 ± 5.8 vs 18.6 ± 22.9 s; P<0.05). Sideeffects of adenosine such as flush, dyspnoea, and chest paindid not seem to be dose dependent and occurred in about 20%. According to our protocol, in more than 75% SR was achievedin patients with sustained tachycardias after vagal manoeuvresand adenosine. 相似文献
43.
目的:探讨房室结折返性心动过速(AVNRT)射频消融术后的电生理改变及不同手术终点与复发率的关系。 方法:本组56 例AVNRT患者慢径消融前、后作各项电生理参数测定,并随访观察远期疗效。 结果:38 例慢径消失者(A组)无一例复发,残存慢径12 例(B组)有一例复发(8.33% ),残存慢径有1~2 个心房回波者6例(C组)有2例复发(33.3% )。53 例无复发者消融前后的房室束最大值(A-Hm ax )分别为(280±27)和(196±56)m s(P<0.01),快径不应期分别为(330±44)和(287±31)m s(P< 0.01)。而3 例复发者消融前、后的A-Hm ax分别为(287±31)和(262±38)m s(P> 0.05),快径不应期分别为(324±38)和(313±28)m s(P> 0.05)。 结论:AVNRT的复发与慢径残存和A-Hm ax 及快径不应期无明显改变有关。 相似文献
44.
45.
目的:利用超声心动图检测正常人左侧房室平面位移幅度。方法:被检对象为144 例正常人,男72 例,女72 例。按不同年龄分为6 组,分别为:Ⅰ组(n= 24 ,3~6 岁);Ⅱ组(n=24 ,7~14 岁) ;Ⅲ组(n=24,15~19 岁) ;Ⅳ组(n= 24,20~39 岁);Ⅴ组(n=24 ,40 ~59 岁) 及Ⅵ组(n= 24 ,≥60 岁)。结果:①左心收缩期房室平面位移测值在Ⅰ组~Ⅴ组之间无显著性差异( P>0-05),而Ⅵ组测值较Ⅰ组~Ⅴ组的测值均低( P< 0-05);②左心收缩期房室平面位移测值不受心率、血压、体表面积及性别的影响。结论:①左侧房室平面位移测值受年龄因素影响;②制定正常左侧房室平面位移测值可以不考虑心率、血压、体表面积及性别的影响 相似文献
46.
观察微波消融犬室性心动过速(简称室速)疗效和微波消融对血液动力学的影响。健康犬40只,随机分成5组,Ⅰ组(对照组,n=8),Ⅱ、Ⅲ、Ⅳ和Ⅴ组(消融组,n=8),由股动脉、股静脉穿刺进行血液动力学监测。用0.01ml0.03%乌头碱注入心室壁诱发室性心动过速。消融释放功率和时间Ⅱ组为40W×30s,Ⅲ组为40W×60s,Ⅳ组为80W×30s,Ⅴ组为80W×60s。结果:自发放微波能量至室速终止时间Ⅱ、Ⅲ组为(10.1±2.4)s,与对照组比,P<0.001;Ⅳ、Ⅴ组为(5.3±1.5)s,与对照组比,P<0.001。消融前后血液动力学各项指标差异无统计学意义(P>0.05),消融后组间血液动力学各项指标差异无统计学意义(P>0.05)。微波产生的心肌损伤,显微镜下观察均为凝固性坏死,与周围组织存在清晰的界限。结论:微波消融室速具有较好的疗效,消融能量与时间在一定范围内对血液动力学无明显影响,可望成为室速治疗的1种新方法。 相似文献
47.
Bhandari AK 《Indian journal of pediatrics》1996,63(5):609-613
Radiofrequency (RF) catheter ablation has ushered in a new era in the management of patients with symptomatic tachyarrhythmias.
By providing the ability to cure the underlying arrhythmic substrate, RF catheter ablation obviates the need for life-long
antiarrhythmic drugs. In the reported series, the success has been high and the complications have been infrequent and relatively
minor. Not unexpectedly, RF catheter ablation has become the treatment of choice for patients with symptomatic paroxysmal
tachyarrhythmias. The role of radiofrequency catheter ablation in infants and small children remains controversial, and awaits
a larger experience and longer follow-up data. 相似文献
48.
胎儿房室结微血管构筑的扫描电镜观察 总被引:4,自引:1,他引:3
用血管铸型结合扫描电镜方法观察了7例胎儿房室结微血管构筑.微动脉反复分支呈树状,行走方式呈波浪形或螺旋形.毛细血管网可分为内外两层:外层纵行为主,以"H"或"Y"形吻合;内层弯曲行走为主,并互相交错吻合.以房室结动脉主干为界,其下方毛细血管密度较大,其上方及前方较小.房室结的上方、前下方和后下方均有微动脉连接毛细血管网.整个结的毛细血管大致可分为结后部上方、下方及前部三个区域.靠毛细血管网外层处可见管径较粗、呈袋状的微静脉. 相似文献
49.
Fascicular tachycardia sensitive to calcium antagonists 总被引:3,自引:0,他引:3
Five patients with recurrent tachycardias exhibiting right bundlebranch block with left axis deviation were referred for investigation.In each case, a supraventricular mechanism was suspected. Duringsinus rhythm, the QRS morphology and axis (10 to +60degrees) and HV intervals were normal. Tachycardia was initiatedby timed ventricular premature stimuli in 4 patients, rapidventricular pacing in 3 patients and rapid atrial pacing in2 patients. The tachycardia cycle length varied from 275 to380 ms with right bundle branch block and a leftward axis changeof 30 to 125 degrees at the onset of the tachycardia. The HVinterval ranged from +15 to 20 ms. In each patient ventriculoatrialdissociation occurred spontaneously or could be induced. Alltachycardias could be terminated or greatly slowed by calciumantagonists. These data are consistent with an unusual reentrantmechanism of tachycardia located in the posterior fascicle ofthe left bundle branch. 相似文献
50.
Tohru Ozaki Toshihiko Uematsu Satoru Nagashima Masahiko Nishimoto Mitsuyoshi Nakashima 《Naunyn-Schmiedeberg's archives of pharmacology》1991,344(4):478-487
Summary DPI 201-106 (DPI), a novel and potent cardiotonic agent, exhibits its effects by prolonging the open state of Na+ channels, resulting in an increase in action potential duration, and thus, is supposed to share the class III antiarrhythmic activity. The effects of DPI on the hemodynamics, intraventricular conduction and refractoriness of heart, and the incidence of arrhythmias induced by programmed electrical ventricular stimulation (PES) were compared with (±)-dobutamine. Dogs which survived for 5 to 7 days after the induction of myocardial infarction were used as the model. The presence of sub-acute myocardial infarction caused by occluding the left anterior descending coronary artery elicited a mild left ventricular dysfunction represented by a significant decrease in peak LV dp/dt by about 20%.Both i.v. bolus injection of DPI (1, 3 and 5 mg/kg) and i. v. continuous infusion of dobutamine (3, 5 and 10 g/kg/min), which were administered in a cumulative manner, dose-dependently improved the hemodynamic parameters. At the higher doses of both DPI (3 and 5 mg/kg) and dobutamine (5 and 10 g/kg/min) the control values were reached or even exceeded. DPI dose-dependently increased the effective refractory period (ERP) of both non-infarcted and infarcted ventricular myocardia to a similar degree, but the conduction time showed a frequency-dependent increase in the infarcted myocardium to a greater degree than in the non-infarcted myocardium after DPI. In contrast, dobutamine decreased the ERP in both non-infarcted and infarcted myocardia, and slightly increased the difference of refractoriness between the non-infarcted and infarcted zones with no effect on the intraventricular conduction. In the PES study, DPI (3 and 5 mg/kg) produced a significant decrease in the incidence of ventricular tachycardia, whereas dobutamine (5 and 10 g/kg/min) tended to worsen the arrhythmias. These findings suggest that cardiotonic agents with a class III antiarrhythmic property such as DPI may be potentially useful for the management of heart failure accompanied by ischemic heart disease.Abbreviations DPI, DPI 201-106; PES
programmed electrical ventricular stimulation
- LV dp/dt
the rate of rise of left ventricular pressure
- ERP
effective refractory period
- RVOT
right ventricular outflow tract
- VT
ventricular tachycardia
- LAD
left anterior discending coronary artery
Send offprint requests to T. Uematsu at the above address 相似文献