风湿性心脏病心外膜标测心房电位的对比研究

采用术中心外膜标测方法 ,对风湿性心脏病 (简称风心病 )慢性心房颤动 (简称房颤 )及其电复律后窦性心律、风心病窦性心律及非风心病窦性心律的心房电位进行比较研究。选择风心病慢性房颤患者 18例 (Ⅰ组 )、风心病窦性心律患者 9例 (Ⅱ组 )、非风心病窦性心律患者 8例 (Ⅲ组 ) ,采用 18导同步心外膜标测 ,通过心外膜电图对房波电位顺序进行分析 ,并对三组患者的心房有效不应期 (ERP)进行比较。结果 :窦性心律患者 (Ⅱ组与Ⅲ组 )以右房侧壁上部房波电位最为领先 ,慢性房颤患者 (Ⅰ组 )左房房波多以后下部最为领先 ;Ⅰ组心房ERP最短 ,Ⅱ组次之 ,Ⅲ组最长 ,以左房后壁中部、中下部、下部相差最为明显 (P <0 .0 1) ,而心房其它部位亦有显著差异 ,P <0 .0 5 ;Ⅰ组左房与右房ERP比较 ,左房中、中下及下部ERP均明显短于右房相应部位的ERP(P <0 .0 5 ) ;Ⅰ组中左房传导时间均明显长于Ⅱ组与Ⅲ组 (P <0 .0 1)。结论 :风心病慢性房颤患者的房波电位多起源于左房 ,其左房传导时间明显长于窦性心律患者 ,而心房ERP明显短于窦性心律患者。     

风湿性心脏病慢性心房颤动左侧迷宫术的电生理观察

目的探讨风湿性心脏病慢性心房颤动（房颤）心外膜标测图形特征及左侧迷宫和左房隔离术消除房颤近期及远期效果。方法１７例风湿性心脏病慢性房颤患者有明确房颤病史平均２．０±２．３年,均有二尖瓣疾患合并主动脉或三尖瓣疾患需手术治疗。根据不同术式分为：（１）左侧迷宫组５例;（２）左房隔离组９例;（３）左房冷冻或左心耳结扎组３例。采用左房右房１６导联同步心外膜标测。结果（１）心外膜标测左房异常电图分析：左房后壁中部为慢性传导区,发生率２３．５％,双峰电位发生率以左房后壁最高３９．３７％,依次为左房上部２５．６％,左房下部９％,左心耳５．６％。碎裂电位发生率以左房后壁中部最高１７．４％,依次为左房上部１０．６６％,左心耳２．５％,左房下部０．８％。（２）左侧迷宫术后心外膜标测,３例双房均示窦性心律,２例双房均示心房扑动,无房颤。随访６周以上者均为窦性心律。（３）左房隔离术后３个月窦性心律达２２％（２／９）,随访半年以上窦性心律达５例（５／８）,随访２年以上者窦性心律达４例（４／８）。结论本研究提示风湿性心脏病慢性房颤左房后壁中部存在缓慢传导区,单纯作左侧迷宫术近期随访和左房隔离术远期随访的成功率分别为８０％和５０％。     

心房颤动环肺静脉隔离术后复发左房房性心动过速的特点及消融治疗

目的探讨心房颤动(简称房颤)环肺静脉隔离术后(CPVI)复发左房房性心动过速(简称房速)再次射频消融中,房速机制的鉴别和消融策略的选择。方法18例房颤经CPVI术后复发房速患者,其中男16例,女2例,年龄61.4±6.5(50～70)岁。在持续稳定的自发/诱发房速时在Carto指导下行激动顺序标测,经电生理检测,明确房速机制并选择相应消融方式:对于局灶性房速,重新阻断原消融径线上裂隙或消融最早激动区;对于折返性房速,明确关键峡部,行线性消融,如果有肺静脉电位亦行对裂隙的消融。结果共有13例肺静脉恢复电活动(72.7%)。局灶性房速6例,折返性房速12例(包括11例左房大折返和1例肺静脉-左房折返)。相应方式消融后房速均转为窦性心律,且肺静脉电位消失。结论房颤CPVI术后复发的左房房速与肺静脉电位的恢复密切相关;与消融线和裂隙形成的折返有关。     

风湿性心脏病慢性心房颤动右侧迷宫术的电生理观察

目的 术中监测右侧迷宫术对风湿性心脏病慢性心房颤动(房颤)电生理的影响。方法 采用心外膜标测技术对7例风湿性心脏病慢性房颤右侧迷宫术每一切口发生的电生理变化进行分析，术后进行心电随随访观察。结果 (1)术前心外膜标测右房^Ⅲ型房颤占6／7，左房多为单一折返的I型房颤或心房扑动(房扑)占5／7。(2)手术切割或冷冻右房时，左房标测图形无变化。(3)左房后壁中下部呈低振幅、规律、快速的反复激动，最为领先的部位是双电位区。(4)右房标测图形随切割冷冻步骤产生变化，由房颤转为房扑，房性或窦性心动过速。(5)术后平均随访3．7±2.9个月，全组病例均为房颤，心功能Ⅱ级。结论 风湿性心脏病联合瓣膜病慢性房颤在完成瓣膜置挠术的同时仅作右侧迷宫术不能消除房颤，电生理和手术的结果证明房颤的起源在左房，左房后壁中下部低振幅，规律、快速的双电位房波是风湿性心脏病慢性房颤的起源。     

心房扑动患者中心房缓慢传导区的证实

在10例经典Ⅰ型房扑病人进行心内膜标测。用探查电极在30个间隔相等的右房记录部位系统和顺序地记录双极电图,测定各部位的激动时间及相对的激动顺序。然后进行快速心房起搏。完成后静注普鲁卡因胺,转为窦性心律之后再次进行右房标测和用类似房扑的频率做心房起搏。测定从起搏部位到达其他部位的时间,并将窦性心律和房扑时得到的资料进行比较。激动顺序标测提示右房游离壁呈头-尾方向激动,房间隔呈尾-头方向激动,提示右房内有一个折返环存在。6例在整个房扑周期都可记录到电活     

一种新的简化方法验证左心房顶部线性阻滞

目的 评价一种新的简化方法验证左心房顶部线完全传导阻滞的可靠性.方法 对31例阵发性心房颤动（房颤）患者双侧肺静脉完全电隔离后进行预部线消融,在窦性心律下用一种新的简化方法评价顶部线是否完全阻滞.假定在窦性心律下,左心房后壁的激动顺序发生变化（变为自下而上）和/或沿顶部消融线记录到连续分布的双电位,顶部线完全传导阻滞即实现.检验结果将与经典的起搏方法进行比较.结果 用简化的方法对31例患者的左心房顶部线进行评价,初次消融后8例未实现传导阻滞,再次标测及消融后所有患者顶部线均实现完全传导阻滞.25例沿左心房顶部消融线可记录到双电位,电位间距为（60±13）ms.窦性心律下左心房顶部左右两端传导延迟（87±11）ms和（82±9）ms（从左心房最早激动算起）,左心耳起搏时左、右两端传导延迟（129±13）ms（P＜0.05）和（135±22）ms（P＜0.05）.该方法评价左心房顶部完全线性阻滞的敏感性、特异性、阳性预测值及阴性预测值分别为100%,88.9%,96.8%和100%.结论 窦性心律下左心房后壁激动顺序变为自下而上以及沿顶部消融线连续双电位分布,提示顶部线性阻滞实现.     

房性心动过速的起源部位及心电图特征

通过常规方法或三维电解剖标测系统(CARTO)精确定位26例房性心动过速(简称房速)的起源部位,右房起源房速23例:界嵴5例,冠状静脉窦口5例,房间隔右侧3例,Koch三角2例,右心耳1例,上腔静脉1例,余右房各壁各1例。左房起源房速3例均为右上肺静脉。V1导联P波双向或负向者房速多起源于右房;P波正向或双向的房速起源于左房;aVL导联及Ⅰ导联P波正向对诊断右房房速有意义。     

左房房性心动过速三维电磁导管标测系统(Carto)标测与射频消融

目的探讨左房房性心动过速(房速)三维电磁导管标测系统(Carto)系统标测特点及射频消融价值.方法 9例左房房速患者,应用Carto系统标测左心房,实时重建左房三维电解剖图;根据电解剖图,判断房速类型局灶性或大折返性房速;于心房最早激动点处或折返环的关键峡部消融.结果 9例患者中共有10个房速.在冠状静脉窦(CS) 电极中、远端或近端均记录到相对提早A波;9个房速为局灶性房速,激动图显示最早激动点位于肺静脉口部(5个)、左房后壁(2个)、左心耳口部(1个)、左心耳体部(1个);1个为大折返性房速,折返经过右上肺静脉口部与卵圆窝之间关键峡部.8个局灶性房速在上述最早激动点处消融,均成功终止房速,1个左心耳体部房速消融失败;大折返性房速于关键峡部行线性消融,获成功;随访6～30个月,其中1例局灶性房速术后次日复发,再次消融成功;无并发症;成功病例手术时间为90～140 min,X线照射时间为8～16 min.结论本组结果提示,应用Carto系统标测左房房速,判断房速类型准确、快速;指导消融安全、有效,可减少X线照射时间,进一步提高消融成功率,特别是对于常规方法消融失败病例尤有帮助.     

CARTO系统指导射频消融的应用评价

目的对比研究CARTO标测系统在指导消融术中的弊与利.方法 6例病人同时接受CARTO及普通心内电信号标测双系统指导下的射频消融.其中左房局灶性房速3例、右房房速1例、左室非典型部位特发性室速1例、先心矫形及修补术后室速1例.除1例房速外,均为接受第二或第三次手术的病人,普通心内电信号标测同常规,CARTO电解剖标测系统利用电磁原理首先建立感兴趣区的三维空间,然后诱发心动过速,心动过速时标测折返环,窦性心律下或心动过速时进行消融.结果 6例病人成功4例.未成功的两例病人为因心包填塞中止手术的患者,其中1例为左房局灶性房速、1例左室非典型部位特发性室速,心包穿刺后缓解,无1例死亡.结论 CARTO电解剖标测系统的优点在于可以术中描绘出心动过速的折返环路、无须太多的X线曝光量、提高复杂心律失常射频消融的成功率,节省手术时间.但对于简单心律失常来讲,建立感兴趣区的三维结构,要耗用不必要的标测时间,使简单问题复杂化,此外费用较高.由于CARTO系统无法观察到整个导管的走性情况,导管在心腔内的张力无法判断,因此容易出现心包填塞等并发症.因此CARTO电解剖标测系统的主要优势在于器质性心脏病引起的复杂心律失常的射频消融.     

经主动脉无冠窦内射频消融局灶性房性心动过速

目的探讨起源于主动脉无冠窦或其邻近组织的局灶性房性心动过速(简称房速)心脏电生理特点及经射频导管消融方法。方法 13例患者男3例,女10例,年龄52.7±9.8岁,阵发性房速病史4.2±4.5年。心房刺激诱发房速后,分析体表心电图P′波特点并于右房及主动脉无冠窦内进行激动标测。均于无冠窦内进行射频消融治疗。结果 13例心房刺激均能反复诱发或终止房速,平均周长340.9±46.0ms,房速时P′波时限77.8±14.4ms,明显短于窦性心律时P波时限111.2±10.3ms(P0.05)。常规激动标测,所有患者于His束处标测到相对提前的心房激动。经主动脉逆行方法 ,所有患者于无冠窦内标测到心房激动较His束处的心房激动提前9.3±6.1ms,放电1～2次于2～8s内终止房速。随访3～36个月,无复发病例及手术相关合并症。结论起源于主动脉无冠窦或其邻近组织的房速具有窄P′波及常规标测相对提前的心房激动位于His束处的特点。经主动脉无冠窦内标测消融是一种根治此类房速安全有效的方法 。     

Identification of left atrial origin of ectopic tachycardia during right atrial mapping: analysis of double potentials at the posteromedial right atrium

INTRODUCTION: The high posteromedial right atrium is adjacent to the left atrium near the right superior pulmonary vein. We hypothesized that analysis of electrograms at this site could distinguish left from right atrial tachycardia. METHODS AND RESULTS: Atrial mapping was performed in 16 patients with left atrial origin ectopic tachycardia (11 patients with right superior pulmonary vein origin and 5 patients with other left atrial tachycardias). During left atrial tachycardia, earliest right atrial activation was recorded at the high posterior right atrium in 14 of 16 patients. At all of these 14 early sites, double potentials were recorded during tachycardia. The first potential was a far-field signal from left atrium as indicated by the following: (1) during sinus beats, the timing of the two potentials reversed such that the left atrial one was late; (2) ablation at the right atrial site did not decrease the amplitude of the first potential, but did decrease the amplitude of the second potential; and (3) the timing of activation at the adjacent left atrium agreed with that of the first potential. In the 11 right superior pulmonary vein tachycardias, the first potential was markedly earlier than the p wave onset, but in left atrial tachycardias with other origins it was later. In a control group of six patients with pacing to simulate right atrial tachycardia, double potentials were recorded in the posterior right atrium, but the timing of components did not reverse during sinus rhythm. CONCLUSION: For some left atrial ectopic tachycardias, particularly those originating from the right superior pulmonary vein, recognition of left versus right atrial origin can be accomplished during right atrial mapping by analysis of double potentials in the posteromedial right atrium.     

Electrophysiologic characteristics of atrial tachycardia originating from the right pulmonary veins or posterior right atrium: double potentials obtained from the posterior wall of the right atrium can be useful to predict foci of atrial tachycardia in right pulmonary veins or posterior right atrium

INTRODUCTION: The right pulmonary veins (RPVs) and posterior wall of the right atrium (PRA) are anatomically located adjacent to each other. The aim of this study was to demonstrate the electrophysiologic characteristics of atrial tachycardia (AT) originating from the PRA or RPVs. METHODS AND RESULTS: A total of 26 consecutive patients with AT originating from the RPVs or PRA underwent detailed atrial endocardial mapping and successful radiofrequency catheter ablation. Eight foci were found in the PRA and 18 foci in the RPVs. Analysis of P wave configuration showed that lead V1 was the most helpful in distinguishing the AT foci between these two sites. In all cases, double potential (DP) configurations were recorded from several electrodes of a multielectrode catheter placed in the PRA, and the first DP component (FP) was the earliest potential recorded from the right atrium during the tachycardia. The amplitude of the FP was higher than that of the second DP component (SP) for AT foci originating in the PRA, whereas the reverse occurred for those in the RPV. The activation sequence of the FP was from superior to inferior for the AT foci in the superior RPV, whereas the reverse occurred for the AT foci in the inferior RPV. CONCLUSION: P wave configuration in lead V1 is helpful in distinguishing AT foci between those originating in the PRA and RPVs. The DPs obtained from the PRA can be useful in predicting whether AT foci originate from the PRA or RPVs.     

Simple and accurate catheter mapping technique to predict atrial fibrillation foci in the pulmonary veins or posterior right atrium.

OBJECTIVES: The purpose of this study was to investigate the efficacy of a novel catheter mapping technique for predicting atrial fibrillation (AF) foci. BACKGROUND: Most AF originates from pulmonary veins (PVs), but some originate from the right atrium. METHODS: We developed an algorithm by correlating the cardiac recordings obtained from multielectrode catheters placed in the posterior right atrium (RA) and esophagus during pacing from the PVs and superior vena cava (SVC) or crista terminalis (CT) in 10 AF patients. We tested the algorithm's accuracy prospectively in 46 AF patients. RESULTS: During pacing from the left PVs, the esophageal potentials preceded all other potentials. During pacing from both the right PVs and SVC-CT, the first component (FP) of the double potential (DP) recorded in the posterior RA preceded all other potentials. The amplitude of the FP was higher than that of the second DP component during pacing from the SVC-CT, whereas the reverse occurred from the right PVs. The activation sequence of the FPs and esophageal potentials was from superior to inferior during pacing from the superior PVs, whereas the reverse occurred from the inferior PVs. The accuracy of predicting 34 foci in the right PVs, 28 foci in left PVs, and 6 foci in SVC-CT was 100% for all, respectively. The accuracy of discriminating foci in the superior PVs from those in the inferior PVs was 97% in the right PVs and 96% in the left PVs. CONCLUSIONS: The technique using mapping catheters placed in the posterior RA and esophagus is feasible and effective for mapping and ablating AF.     

Coronary sinus recordings of double potentials associated with retrograde conduction through left atrioventricular accessory pathways

INTRODUCTION: In some patients with left AV accessory pathway (AP), double potentials are recorded along the coronary sinus (CS) during retrograde AP conduction only. This electrophysiologic study was performed to clarify the origin and clinical significance of double potentials in 11 patients. METHODS AND RESULTS: The direction of activation of the first, relatively blunt component (DP1) was lateral to septal in 5 patients with anterior or anterolateral AP, centrifugal in 2 patients with posterior or posterolateral AP, and septal to lateral in 4 patients with posteroseptal AP, suggesting the earliest activation of DP1 was near the AP. The direction of activation of the second, sharper potentials (DP2) were septal to lateral in all patients. The double potentials were fused in the paraseptal CS region. Pacing from the lateral CS musculature or lateral left atrium reproduced the double potentials. The effective refractory period of the double potentials was reached by ventricular extrastimulation, and the left atrial deflection preceded the double potentials, excluding a ventricular or AP origin. CONCLUSION: In patients with connections between the paraseptal CS musculature and left atrium but no connections more laterally, retrograde left AP conduction is associated with double potentials in the CS recordings. The double potentials represent activation of the left atrial insertion of the AP (DP1) and later activation of the CS musculature (DP2) via connections between the paraseptal CS musculature and left atrium, respectively. The activation pattern of DP1 depends on AP location, thus providing important information for AP localization during CS mapping.     

Characterization of double potentials in human atrial flutter: studies during transient entrainment

Double potentials, defined as atrial electrograms with two discrete deflections per beat separated by an isoelectric interval or a low amplitude baseline, have been observed during right atrial endocardial mapping of human atrial flutter. In this study, bipolar atrial electrograms were recorded during atrial flutter (mean cycle length 235 +/- 27 ms [+/- SEM]) from the high right atrium, the His bundle region, the coronary sinus and at least 30 right atrial endocardial mapping sites in 10 patients. Double potentials were recorded from the right atrium in all patients during atrial flutter. Double potentials were evaluated during transient entrainment of atrial flutter by rapid high right atrial pacing in 5 of the 10 patients. In four of these five patients during such transient entrainment 1) one deflection of the double potential was captured with a relatively short activation time (mean interval 89 +/- 45 ms) and the other deflection was captured with a relatively long activation time (mean interval 233 +/- 24 ms), producing a paradoxical decrease in the short interdeflection interval from a mean of 75 +/- 20 ms to a mean of 59 +/- 24 ms; and 2) the configuration of the double potential remained similar to that observed during spontaneous atrial flutter. On pacing termination 1) the two double potential deflections were found to be associated with two different atrial flutter complexes in the electrocardiogram (ECG); 2) the previous double potential deflection relation resumed; and 3) when sinus rhythm was present, the double potentials were replaced by a broad, low amplitude electrogram recording at the same site.(ABSTRACT TRUNCATED AT 250 WORDS)     

Identifying far-field superior vena cava potentials within the right superior pulmonary vein

BACKGROUND: Far-field extra-pulmonary vein (PV) potentials originating from the left atrial appendage and adjacent left atrium have been identified within the left PVs, but no systematic study of extra-PV potentials within the right superior PV (RSPV) has been described. OBJECTIVES: The purpose of this study was to prospectively analyze extra-PV contributions to RSPV potentials. METHODS: In a consecutive, prospective series of 114 patients (96 men and 18 women; 56 +/- 10 years) undergoing electrophysiologically guided ostial PV isolation, residual potentials recorded with a circular mapping catheter in the RSPV after ostial isolation were analyzed. Their extra-PV origin was validated by mapping a site with identical timing (in sinus rhythm or atrial fibrillation) within the adjacent superior vena cava (SVC) where, in sinus rhythm, local pacing (until threshold amplitude) concealed the residual potential within the stimulus artifact because of very short activation timing. The timing of residual potentials with respect to surface ECG P-wave onset was measured and compared with the earliest timing of ablated RSPV potentials. RESULTS: Residual low-amplitude (mean 0.29 +/- 0.17 mV, range 0.07-0.65 mV) extra-PV potentials were recorded from the anterior and superior aspect of the RSPV in 3.6 +/- 1 bipoles in 26 (23%) patients (all men, 51 +/- 10 years) with a timing from sinus P-wave onset of 17 +/- 12 ms (range 0-40 ms) vs 52 +/- 9 ms (range 35-70 ms) for the earliest RSPV potential (P <.001, t-test). Extra-PV potentials all originated from the posterior aspect of the SVC. The SVC potential was identified during ongoing atrial fibrillation in eight patients and later confirmed in sinus rhythm. An extra-PV potential of SVC origin could be identified by timing earlier than 30 ms from onset of the sinus P wave, with sensitivity of 92%, specificity 100%, positive predictive value 100%, and negative predictive value 89%. CONCLUSION: Extra-PV potentials of right-sided SVC origin were recorded within the RSPV in 23% of patients and can be identified with high sensitivity and specificity by a timing within 30 ms of sinus P-wave onset. Recognizing these potentials can avoid unnecessary additional ablation and possibly PV stenosis or phrenic paralysis.     

Ectopic right atrial rhythms: experimental and clinical data

In 18 out of 25 canine hearts studied with bipolar plunge electrodes, ectopic right atrial (RA) beats were observed occurring (1) spontaneously, (2) during vagal stimulation, (3) after destruction of the sinus node, and (4) during ventricular pacing. In these beats the RA appendage was activated first, followed by Bachmann's bundle, sinus node, left atrial appendage, posterior left atrium, and proximal coronary sinus. This sequence was consistently reproduced by pacing through the RA appendage recording electrode.     

Absence of left atrium-coronary sinus musculature electrical connection at coronary sinus ostium unmasked by unique double coronary sinus potentials pattern

We describe a 77-year-old man with Wolff-Parkinson-White syndrome exhibiting double coronary sinus (CS) potentials during retrograde conduction over accessory pathway (AP). The first, low-frequency potential (DP1) was first recorded in the left posterolateral region, while the second, higher frequency signal (DP2) was recorded in a lateral-to-septal direction. The two signals were fused near the left lateral wall. Successful ablation of the AP was obtained at its ventricular insertion site in the postero-septal region. The unexpectedly delayed activation of the paraseptal RA following activation of the paraseptal left atrium (DP1) can be explained by the absence of a LA-CS musculature (CSM) electrical connection at the proximal CS, which forces a detour of the activation wavefront from LA to RA via the distal CS (DP2). This is a rare case exhibiting unique double CS potentials which unmasked the absence of a LA-CSM electrical connection at CS ostium.     

Predicting the arrhythmogenic foci of atrial fibrillation before atrial transseptal procedure: implication for catheter ablation

INTRODUCTION: Use of endocardial atrial activation sequences from recording catheters in the right atrium, His bundle, and coronary sinus to predict the location of initiating foci of atrial fibrillation (AF) before an atrial transseptal procedure has not been reported. The purpose of the present study was to develop an algorithm using endocardial atrial activation sequences to predict the location of initiating foci of AF before transseptal procedure. METHODS AND RESULTS: Seventy-five patients (60 men and 15 women, age 68 +/- 12 years) with frequent episodes of paroxysmal AF were referred for radiofrequency ablation. By retrospective analysis, characteristics of the endocardial atrial activation sequences of right atrial, His-bundle, and coronary sinus catheters from the initial 37 patients were correlated with the location of initiating foci of AF, which were confirmed by successful ablation. The endocardial atrial activation sequences of the other 38 patients were evaluated prospectively to predict the location of initiating foci of AF before transseptal procedure using the algorithm derived from the retrospective analysis. Accuracy of the value <0 msec (obtained by subtracting the time interval between high right atrium and His-bundle atrial activation during atrial premature beats from that obtained during sinus rhythm) for discriminating the superior vena cava or upper portion of the crista terminalis from the pulmonary vein (PV) foci was 100%. When the interval between atrial activation of ostial and distal pairs of the coronary sinus catheter of the atrial premature beats was <0 msec, the accuracy for discriminating left PV foci from right PV foci was 92% in the 24 foci from the left PVs and 100% in the 19 foci from the right PVs. CONCLUSION: Endocardial atrial activation sequences from right atrial, His-bundle, and coronary sinus catheters can accurately predict the location of initiating foci of AF before transseptal procedure. This may facilitate mapping and radiofrequency ablation of paroxysmal AF.