体表心电图对房室结折返性与房室折返性心动过速的鉴别诊断

为探讨体表心电图对房室结折返性和房室折返性心动过速的鉴别诊断价值,对以射频导管消融、心脏电生理检查、心外膜标测的方法确诊房室结折返性心动过速(AVNRT)和房室折返性心动过速(AVRT)的88例患者的室上性心动过速发作时心电图作对照研究。结果显示:(1)P'波出现率在AVNRT占33％,在AVRT占100％(P<0.01)。(2)R-P'间期<80ms时常见于AVNRT,而≥80ms多见于AVRT(P<0.01)。(3)AVNRT在下壁导联(Ⅱ、Ⅲ、aVF)常见假性S波,而V_1导联常合并假性r波。(4)AVRT无文氏现象,但常出现束支传导阻滞改变且符合Coumel-Slama定律。认为以上特点对两者鉴别诊断有重要价值。     

房室结折返性心动过速伴心室不同比例传导一例

男性,59岁,10年前出现阵发性心慌、心悸,伴胸闷、气短,情绪激动后易发作,呈突发突止特征。行食管调搏检测中诱发出慢快型房室结折返性心动过速（AVNRT）,心动过速开始时为心室出现不同比例传导,出现一次室性早搏,后心动过速则出现1 颐1的规则传导。     

房室结折返性心动过速伴额外心房激动的心内电图表现

房室结折返性心动过速(Atrioventricular Nodal Reentrant Tachycardia,AVNRT)是一复杂但又连续的心律失常谱,发生AVNRT的核心和本质是房室结和(或)房室结附近心房肌的折返激动。脱离AVNRT时心房不应期的额外心房激动可再次夺获心房并可通过侵入AVNRT的折返环在不影响其后第1个His束-心室激动时间的情况下使其后第2个His束-心室激动提前发生,交界区自律性心动过速不具有这一特点。AVNRT伴额外心房激动的心电学特点丰富了AVNRT的心律失常谱,也使我们更深刻的认识了AVNRT的本质。     

房室折返性心动过速伴心室内差异性传导酷似室性心动过速1例

患者男性,61岁。因阵发性心悸6年就诊,每次发作数分钟至数小时不等,能白行终止,呈突发突止。体检：BP120／80mmHg。心率75次／min,心律齐,心脏听诊未闻及病理性杂音,超声心动描记术检查未见明显异常。临床诊断：阵发性室上性心动过速。心电图（图1A）示窦性心律,     

房室结折返性心动过速室房传导的规律

通过窄 QRS心动过速的心电图 RP′间期及心内电图VA间期变化 ,探讨房室结折返性心动过速 (atrioventriculanodal reentrant tachycardia,AVNRT)室房传导的规律性。　　资料和方法　选择对象为经心内电生理检查及射频消融治疗证实为房室结双经路慢 -快型折返性心动过速的 46例患者 ,男性 2 0例 ,女性 2 6例 ,平均年龄 (4 4± 15 )岁。 46例患者 ,窦性心律时心电图无异常 ,心动过速时呈窄 QRS波 ,QRS时限 <0 .11s,伴 1∶ 1的室房激动关系 ,心动过速时记录体表心电图及希氏束 (HBE)及冠状静脉窦近端 (CS9～10 )心内电图来观察 RP′间…     

房室结内折返性心动过速—快慢径路传导

随着电生理检查的深入 ,人们对临床电生理的一些理论和现象有了新的认识和提高。现将我院自 1997～ 2 0 0 0年期间 ,房室结内折返性心动过速中 ,具有代表性的 8例患者进行分析如下。8例中 ,男性 6例 ,年龄 3 5～ 64岁 ,其中 1例死亡 ;女性 2例 ,年龄 2 9～ 3 7岁。 8例患者平时均有心悸病史 ,发作时心率 12 0～ 195次 ｍｉｎ ,每次持续数分钟至数十分钟 ,甚至几小时。发作次数从每月数次到每日 1～ 2次。发作时心电图示 :心率 190次 ｍｉｎ ,ＱＲＳ波呈室上性。Ｒ -Ｒ间期匀齐0 3 1ｓ,Ｖ6 Ｒ -Ｐ间期 0 19ｓ,Ｐ -Ｒ间期 0 0 9ｓ,其它导…     

房室结折返性心动过速的特殊心电现象分析

房室结折返性心动过速的特殊心电现象分析施冰江洪陈芳李庚山黄从新许家左进周纪宁（湖北医科大学附属第一医院心内科４３００６０）房室结折返性心动过速（ＡＶＮＲＴ）的形成必须有房室结双径和双径路的传导速度差及不应期差异的存在。其折返环路在房室结内，心房与心...     

常规心电图对典型的房室结折返性心动过速和顺传型房室折返性心动过速的鉴别作用

目的探讨12导联心电图对阵发性窄QRS心动过速中最常见两种类型--典型的房室结折返性心动过速（AVNRT）和顺传型房室折返性心动过速（AVRT）的鉴别作用.方法对206例阵发性窄QRS心动过速（QRS〈0.11 s,心室率〉120次/min）患者的心电图进行了分析.第一部分分析139例患者的心电图,从中归纳出1个12导联心电图算法（algorithm）.第二部分前瞻性分析了67例患者的心电图,以检测这一算法的准确性.心动过速的机制和旁路位置均由成功的射频导管消融术确定.结果 5项心电图指标对区分这两种心动过速类型有意义.对于AVNRT有预测作用的为伪r′波（V1导联,敏感性53%、特异性96%）,伪S波（Ⅱ、Ⅲ、aVF导联,敏感性21%、特异性100%）.对于AVRT有预测作用的为逆传P波（敏感性89%、特异性68%）,RP间期〉70 ms（敏感性90%、特异性91%）,及ST段改变.ST段改变归纳出3个联合指标,分别为：V4、V5导联ST段同时下降≥2 mm（敏感性24%、特异性94%）;V5、V6导联ST段同时下降≥1 mm（敏感性41%、特异性81%）;V6导联ST段同时下降≥1 mm和aVR导联ST段抬高≥1 mm同时出现（敏感性30%、特异性85%）.V1导联逆传P波极性对于旁路的初步定位有帮助,左侧旁路大多为直立、双向或平坦的逆传P波,右侧旁路大多为倒置的逆传P波.12导联心电图算法对心动过速机制的正确诊断率分别为85%和82%.对于AVRT旁路位置的正确判断率为75%～86%.在3个联合指标中,V5、V6导联ST段同时下降≥1 mm的鉴别作用最佳.结论心电图算法有助于更加准确地鉴别阵发性窄QRS心动过速的机制,并且可以对旁路初步定位.     

Atrioventricular conduction patterns in patients with paroxysmal supraventricular tachycardia.

Atrioventricular conduction patterns suggestive of dual A-V nodal pathways have been reported in patients with and without a history of paroxysmal A-V nodal re-entrant tachycardia (PSVT). The purpose of this study was to determine whether significant association exists between this conduction pattern and the occurrence of PSVT in man. The pattern of A-V conduction was evaluated at similar pacing rates in 13 patients with documented PSVT and 135 patients with PSVT. Patients without PSVT were divided into groups with normal PR intervals (106 patients), PR intervals of 120 msec. or less (12 patients), and PR intervals of 200 msec. or greater (17 patients). Evidence of dual A-V nodal pathways was found in seven of 13 patients with PSVT and nine of 135 patients without PSVT, including eight of 106 patients with normal PR intervals, none of 12 patients with short PR intervals, and one of 17 patients with PR intervals of 200 msec. or greater. The incidence of dual A-V nodal pathways was significantly greater (P less than 0.01) in patients with PSVT when compared with all other groups. In two of four patients with PSVT, propranolol was found to unmask evidence of dual pathways; no evidence of dual pathways was produced by propranolol in 23 patients without PSVT. The data show that the pattern of dual A-V nodal pathways is common only in patients with PSVT and is significantly less frequent in patients without PSVT regardless of the presence of short or long PR intervals. The results of this study establish a strong association between this conduction pattern and the occurrence of PSVT in man.     

Comparative study of transesophageal atrial pacing and intracardiac electrophysiology in patients with supraventricular tachycardia

The diagnostic value of transesophageal atrial pacing in supraventricular tachycardia (SVT) has been discussed according to the comparison of the results of intracardiac and transesophageal electrophysiological study. Some quantitative criteria for the differential diagnosis of atrioventricular node reentrant tachycardia (RT-AVN) and atrioventricular reciprocating tachycardia (RT-AP) has been proposed. We found that RT-AVN and RT-AP could be separated by noninvasive transesophageal atrial pacing. We also suggested that induced SVT would be RT-AVN if (1) SR conductive curve was not continuous and SR jump greater than 70 ms, (2) AV interval less than 60 ms, and it would be RT-AP if (1) SR curve was continuous and there was no SR jump phenomenon, (2) VA interval greater than 100 ms. Thus, transesophageal atrial pacing was very helpful in distinguishing the mechanisms of SVT and could provide a simple clinical cardiac electrophysiological procedure in diagnosing SVTs.     

Concealed bypasses of the atrioventricular mode in patients with paroxysmal supraventricular tachycardia revealed by intracardiac electrical stimulation and verapamil

Thirteen patients with paroxysmal Supraventricular tachycardia were studied with use of His bundle electrograms and programmed intracardiac stimulation. No patient had evidence of either the Wolff-Parkinson-White or Lown-Ganong-Levine syndrome. During ventricular pacing at a rate of 90 to 180 beats/min retrograde conduction time increased by an average of 80 msec in eight patients; in the remaining five patients the average increase was only 9 msec. The tachycardia was terminated in all 13 patients after intravenous administration of verapamil, 10 mg. This drug acts predominantly on the atrioventricular (A-V) node, and during termination of an A-V nodal reciprocal tachycardia both the antegrade and retrograde conduction times would be expected to be prolonged. During termination of the tachycardia antegrade conduction was prolonged by an average of 43 msec and retrograde conduction by an average of 79 msec in eight patients. However, in five patients antegrade conduction was prolonged by an average of 101 msec and retrograde conduction by an average of only 3 msec. The minimal effect of this drug on retrograde conduction and the minimal increase in retrograde conduction during ventricular pacing in these five patients is strong evidence for the presence of an A-V nodal bypass that was not apparent from the surface electrocardiogram. The potential hazards should atrlal fibrillation occur and allow rapid antegrade conduction in an A-V nodal bypass are discussed.     

Surgical therapy for patients with supraventricular tachycardia

Surgical techniques have now been developed to treat a variety of supraventricular arrhythmias, including the Wolff-Parkinson-White syndrome, arrhythmias associated with other atrioventricular accessory connections, AV nodal reentrant tachycardia, and automatic (ectopic) atrial tachycardias. In addition, atrial flutter and atrial fibrillation are not potentially curable with surgical intervention. This article will discuss the current surgical techniques used to treat these supraventricular tachyarrhythmias.     

Invasive electrophysiologic evaluation of patients with supraventricular tachycardia

This article describes the clinical and technical aspects of invasive electrophysiology studies in patients with supraventricular tachycardia. The methods and interpretation of programmed stimulation and pharmacologic interventions during sinus rhythm and supraventricular tachycardia are discussed.     

Incidence of symptomatic tachycardia in untreated patients with paroxysmal supraventricular tachycardia

The purpose of this article is to investigate the occurrence of symptomatic paroxysmal supraventricular tachycardia (PSVT) in untreated patients and to assess factors that influenced its occurrence. We studied 34 patients with this arrhythmia during an observation period in which they received no antiarrhythmic drug therapy for up to 90 days. Recurrence of PSVT was documented by telephone transmission of the electrocardiogram. Each patient was allowed to have exactly one episode of tachycardia before being removed from the study. We measured how long patients remained free of their tachycardia (the tachycardia-free period) and heart rate during tachycardia. Twenty-nine of the 34 patients had an attack of symptomatic tachycardia within the 90-day observation period. The proportion of patients who had not had any symptomatic PSVT by each day of follow-up was calculated using the Kaplan-Meier method as follows: 75% by day 3, 50% by day 19, 25% by day 36, and 17% by day 90. Patients with any other heart or lung disease had significantly shorter tachycardia-free periods. The mean heart rate during spontaneous tachycardia was 203.5 +/- 34.9 beats per minute (range, 142 to 288 beats per minute). Patients with longer tachycardia-free periods had significantly faster heart rates during tachycardia.     

Differential effects of intravenous magnesium on atrioventricular node conduction in supraventricular tachycardia

Evidence from noninvasive studies suggests magnesium has a differential effect on atrioventricular nodal (AVN) pathways. To further explore the electrophysiologic effects of intravenous magnesium sulfate (MgSO(4)) on supraventricular tachycardia, with particular reference to AVN conduction pathways, we studied 23 patients with supraventricular tachycardia at the time of electrophysiologic study. Tachycardia cycle length; AH, HV, and VA intervals; anterograde and retrograde Wenckebach thresholds; slow and fast pathway effective refractory periods (ERPs); accessory pathway ERP; right atrial and ventricular ERPs; blood pressure; and serum magnesium were evaluated before and after administration of MgSO(4) during sustained tachycardia. AVN reentry was induced in 14 patients and atrioventricular reentry was induced in 9; 1 of the latter had dual AVN physiology with tachycardia using the slow pathway. Serum magnesium level increased from 0.88 +/- 0.11 to 1.79 +/- 0.14 mmol/L (p <0.0001). Magnesium increased tachycardia cycle length to a greater extent in those with dual AVN physiology than those without: 340 +/- 54 to 370 +/- 57 ms versus 347 +/- 29 to 350 +/- 30 ms (p = 0.01). This was associated with greater increase in AH interval in those with dual AVN physiology than in those without: 241 +/- 59 to 270 +/- 60 ms versus 144 +/- 16 to 140 +/- 20 ms (p = 0.003). Presence of dual AVN physiology was more frequently associated with reversion to sinus rhythm: 5 of 15 versus 0 of 8 (p = 0.06). MgSO(4) did not alter other measured parameters. In conclusion, magnesium increases tachycardia cycle length and AH interval in patients with dual AVN physiology through a dominant effect on the slow AVN pathway.