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Partial cavotricuspid isthmus block before ablation in patients with typical atrial flutter

JOURNAL OF THE AMERICAN COLLEGE OF CARDIOLOGY 1999年第7期33卷 1996-2002页

作者： Takahashi, A Shah, DC Jaïs, P Hocini, M Clementy, J Haïssaguerre, M Hop Cardiol Haut Leveque Bordeaux France

OBJECTIVES The purpose of this study was to prospectively evaluate preexisting partial isthmus block in the context of an electrophysiologically directed linear ablation strategy ibr typical atrial flutter (AF). BACKGROUND Double potentials (DPs) separated by an isoelectric interval have been recognized as markers of local block However, the presence and significance of DPs in the cavotricuspid isthmus during AF before ablation have not been evaluated. METHODS Thirty consecutive patients with AF (counterclockwise: 24, clockwise: 6) were studied during AF. Sequential withdrawal mapping was performed in the cavotricuspid isthmus from the tricuspid valve (TV) to the inferior vena cava (IVC) edge with electrograms coinciding with the center of the surface electrocardiographic plateau during counterclockwise AF or with the initial downslope of the positive flutter wave during clockwise AF. Atrial electrograms along this line were categorized as double, single or fractionated potentials (SPs or FPs). After demarcation of the zone of contiguous DPs, radiofrequency (RF) catheter ablation was performed during AF only at sites with SPs or FPs (other than DPs) on the mapped line. If isthmus conduction still persisted after AF termination, additional RF applications were delivered using the same electrophysiologic strategy of avoiding DPs with an isoelectric interval during low lateral right atrial pacing for filling in the gap of residual conduction. RESULTS Before ablation, no DPs were recorded in the isthmus in 19 patients (63%);DPs were recorded only at the IVC edge in five patients, and only at the TV edge in one patient. A contiguous line of DPs extending through more than half the isthmus to the IVC edge was documented in five patients (17%: group DP). In group DP, AF was terminated with 1.4 +/- 0.5 applications (vs. 5.8 +/- 3.5 in the remaining patients: p < 0.01). Complete isthmus block was achieved with a total of 3.4 +/- 0.5 applications (vs. 12 +/- 6 in the remainin

关键词：心房扑动/并发症心房扑动/病理生理学心房扑动/外科学束支传导阻滞/病因学束支传导阻滞/病理生理学导管消融术电生理学/方法心脏传导系统/病理生理学心脏传导系统/外科学前瞻性研究治疗结果三尖瓣腔静脉下老年人老年人 80以上女(雌)性人类男(雄)性中年人

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Body surface mapping of counterclockwise and clockwise typical atrial flutter: A comparative analysis with endocardial activation sequence mapping

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JOURNAL OF THE AMERICAN COLLEGE OF CARDIOLOGY 2000年第5期35卷 1276-1287页

作者： SippensGroenewegen, A Lesh, MD Roithinger, FX Ellis, WS Steiner, PR Saxon, LA Lee, RJ Scheinman, MM Univ Calif San Francisco Dept Med Sect Cardiac Electrophysiol San Francisco CA 94143 USA Univ Calif San Francisco Cardiovasc Res Inst San Francisco CA 94143 USA

OBJECTIVES This study was directed at developing spatial 62-lead electrocardiogram (ECG) criteria for classification of counterclockwise (CCW) and clockwise (CW) typical atrial flutter (Fl) in patients with and without structural heart disease. BACKGROUND Electrocardiographic classification of CCW and CW typical atrial Fl is frequently hampered by inaccurate and inconclusive scalar waveform analysis of the 12-lead EGG. METHODS Electrocardiogram signals from 62 torso sites and multisite endocardial recordings were obtained during CCW typical atrial Fl (12 patients), CW typical Fl (3 patients), both forms of typical Fl (4 patients) and CCW typical and atypical atrial Fl (1 patient), hll the Fl wave episodes were divided into two or three successive time periods showing stable potential distributions from which integral maps were computed. RESULTS The initial, intermediate and terminal CCW Fl wave map patterns coincided with: 1) caudocranial activation of the right atrial septum and proximal-to-distal coronary sinus activation, 2) craniocaudal activation of the right atrial free wall, and 3) activation of the lateral part of the subeustachian isthmus, respectively. The initial, intermediate and terminal CW Fl wave map patterns corresponded with : 1) craniocaudal right atrial sept;ll activation, 2) activation of the subeustachian isthmus and proximal-to-distal coronary sinus activation, and 3) caudocranial right atrial free wall activation, respectively. A reference set of typical CCW and CW mean integral maps of the three successive Fl wave periods was computed after establishing a high degree of quantitative interpatient integral map pattern correspondence irrespective of the presence or absence of organic heart disease. CONCLUSIONS The 62-lead ECG of CCW and CW typical atrial Fl in man is characterized by a stereotypical spatial voltage distribution that can be directly related to the underlying activation sequence and is highly specific to the direction of Fl wave r

关键词：算法心房扑动/分类心房扑动/诊断心房扑动/药物疗法心房扑动/病因学心房扑动/病理生理学体表电位图/仪器和设备体表电位图/方法判别分析心电描记术/仪器和设备心电描记术/方法心内膜/病理生理学心脏传导系统/病理生理学心脏病/并发症结果可重复性危险因素旋转敏感性与特异性时间因素老年人女(雌)性人类男(雄)性中年人

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Preventing ventricular fibrillation by flattening cardiac restitution

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PROCEEDINGS OF THE NATIONAL ACADEMY OF SCIENCES OF THE UNITED STATES OF AMERICA 2000年第11期97卷 6061-6066页

作者： Garfinkel, A Kim, YH Voroshilovsky, O Qu, ZL Kil, JR Lee, MH Karagueuzian, HS Weiss, JN Chen, PS Univ Calif Los Angeles Sch Med Div Cardiol Dept Med Cardiol Los Angeles CA 90095 USA Univ Calif Los Angeles Sch Med Dept Physiol Sci Los Angeles CA 90095 USA Univ Calif Los Angeles Sch Med Dept Physiol Los Angeles CA 90095 USA Univ Calif Los Angeles Sch Med Cardiovasc Res Lab Los Angeles CA 90095 USA Univ Calif Los Angeles Sch Med Cedars Sinai Med Ctr Los Angeles CA 90095 USA

Ventricular fibrillation is the leading cause of sudden cardiac death. In fibrillation, fragmented electrical waves meander erratically through the heart muscle, creating disordered and ineffective contraction. Theoretical and computer studies, as well as recent experimental evidence, have suggested that fibrillation is created and sustained by the property of restitution of the cardiac action potential duration (that is, its dependence on the previous diastolic interval). The restitution hypothesis states that steeply sloped restitution curves create unstable wave propagation that results in wave break, the event that is necessary for fibrillation. Here we present experimental evidence supporting this idea. In particular, we identify the action of the drug bretylium as a prototype for the future development of effective restitution-based antifibrillatory agents. We show that bretylium acts in accord with the restitution hypothesis: by flattening restitution curves, it prevents wave break and thus prevents fibrillation. It even converts existing fibrillation. either to a periodic state (ventricular tachycardia, which is much more easily controlled) or to quiescent healthy tissue.

关键词：动作电位/药物作用抗心律失常药/药理学抗心律失常药/治疗应用溴苄胺化合物/药理学溴苄胺化合物/治疗应用心脏起搏人工计算机模拟色满卡林/药理学色满卡林/治疗应用心舒期/生理学药物设计药物评价临床前荧光染料心脏传导系统/药物作用心脏传导系统/病理生理学模型生物学吡啶鎓化合物猪心室颤动/药物疗法心室颤动/病理生理学心室颤动/预防和控制动物

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Transverse conduction capabilities of the crista terminalis in patients with atrial flutter and atrial fibrillation

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JOURNAL OF THE AMERICAN COLLEGE OF CARDIOLOGY 1999年第2期34卷 363-373页

作者： Schumacher, B Jung, W Schmidt, H Fischenbeck, C Lewalter, T Hagendorff, A Omran, H Wolpert, C Lüderitz, B Univ Bonn Dept Cardiol D-5300 Bonn Germany

OBJECTIVES In this study, the transverse conduction capabilities of the crista terminalis (CT) were determined during pacing in sinus rhythm in patients with atrial flutter and atrial fibrillation. BACKGOUND It has been demonstrated that the CT is a barrier to transverse conduction during typical atrial flutter. Mapping studies in animal models provide evidence that this is functional. The influence of transverse conduction capabilities of the CT on the development of atrial flutter remains unclear. METHODS The CT was identified by intracardiac echocardiography. The atrial activation at the CT was determined during programmed stimulation with one extrastimulus at five pacing sites anteriorly to the CT in 10 patients with atrial flutter and 10 patients with atrial fibrillation before and after intravenous administration of 2 mg/kg disopyramide. Subsequently, atrial arrhythmias were reinduced. RESULTS At baseline, pacing with longer coupling intervals resulted in a transverse pulse propagation across the CT. During shorter coupling intervals, split electrograms and a marked alteration of the activation sequence of its second component were found, indicating a functional conduction block. In patients with atrial flutter, the longest coupling interval that resulted in a complete transverse conduction block at the CT was significantly longer than that in patients with atrial fibrillation (285 +/- 49 ms vs. 221 +/- 28 ms;p < 0.05). After disopyramide administration, a transverse conduction block occurred at longer coupling intervals as compared with baseline (287 +/- 68 ms vs. 250 +/- 52 ms;p < 0.05). Subsequently , a sustained atrial arrhythmia was inducible in 15 of 20 patients. This was atrial flutter in three patients with previously documented atrial fibrillation and in eight patients with history of atrial flutter. Mapping revealed a conduction block at the CT in all of these patients. CONCLUSIONS It was found that the CT provides transverse conduction capabilities

关键词：抗心律失常药/药理学心房颤动/诊断显像心房颤动/病理生理学心房扑动/诊断显像心房扑动/病理生理学心脏起搏人工丙吡胺/药理学超声心动描记术心电描记术电生理学心脏传导系统/诊断显像心脏传导系统/病理生理学老年人女(雌)性人类男(雄)性中年人

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RECIPROCAL RHYTHM IN PATIENTS WITH NORMAL ELECTROCARDIOGRAM - EVIDENCE FOR DUAL CONDUCTION PATHWAYS

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AMERICAN HEART JOURNAL 1976年第1期91卷 3-10页

作者： TOUBOUL, P HUERTA, F PORTE, J DELAHAYE, JP HOP CARDIOVASC PNEUMOL LAB ELECTROPHYSIOL 69394 LYON FRANCE

The present study refers to six patients in whom an A-V reciprocal rhythm could be documented; in four cases it took the form of sustained tachycardia. None of the patients showed any ECG feature of ventricular pre-excitation (PR interval of more than 0.12 sec. and normal QRS configuration). The extrastimulus method showed, at first, that the A-V conduction time of the premature beat varied only slightly with the decrease of the coupling interval. From a critical A1A2 interval there was a sudden lengthening of A2H2 preceding the occurrence of re-entrant beats. The curve of H1H2 responses reflected these changes, showing two distinct parts. The second part following the slowing of the impulse included the initiation zone of atrial echoes and of reciprocating tachycardia. These results suggest the existence of two A-V pathways, one fast and the other slow. The point at which the break between the two parts of the curve occurred might be related to the effective refractory period of the fast pathway. In the same way, when atrial pacing reached a critical rate, it induced an abrupt increase of AH in five cases. In the sixth patient, A-V conduction time remained unchanged up to 170 per minute. Ventriculoatrial conduction was always observed, the delay of which did not lengthen with the rate. In one case tachycardia could be induced by a premature ventricular beat without lengthening of the V-A time. It is concluded that in spite of a normal PR interval, the presence of dual A-V pathways may be implied in the genesis of reciprocal rhythm.

关键词：房室结/病理生理学心电描记术心房心脏导管插入术心脏传导系统/病理生理学心脏起搏器人工心动过速/病因学心动过速/病理生理学成年人人类男(雄)性中年人

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METABOLISM OF FREE FATTY-ACIDS, GLUCOSE AND CATECHOLAMINES IN ACUTE MYOCARDIAL-INFARCTION - RELATION TO MYOCARDIAL ISCHEMIA AND INFARCT SIZE

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AMERICAN JOURNAL OF CARDIOLOGY 1975年第7期36卷 938-953页

作者： OPIE, LH GROOTE SCHUUR HOSP DEPT MED ISCHAEMIC HEART DIS LABS CAPE TOWN SOUTH AFRICA UNIV CAPE TOWN CAPE TOWN SOUTH AFRICA

The myocardial metabolism of free fatty acids, glucose and catecholamines is reviewed in relation to current trends in the therapy of experimental myocardial infarction. Major modifications in the metabolism of free fatty acids, glucose and catecholamines have already been found after acute myocardial infarction in man, and animal experimental data suggest that such metabolic changes might play a role in the modification of infarct size and sometimes in the development of arrhythmias. However, animal experiments often represent extreme situations and the therapeutic use in man of agents to modify the metabolism of free fatty acids, glucose or catecholamines after myocardial infarction needs intensive investigation before general application. The sum total of the evidence from animal experiments suggests that increased circulating concentrations of free fatty acids and catecholamines, if sufficiently high, may be harmful rather than helpful to the outcome of acute myocardial infarction, and that increased provision of glucose (as glucose, insulin and potassium) may be beneficial. Reservations to these conclusions are that the concentrations used appear to be important factors in catecholamine and free fatty acid effects, and that the mechanism of action of glucose-insulin-potassium is more complex than originally thought.

关键词：腺苷三磷酸/生物合成儿茶酚胺类/代谢冠心病/代谢冠心病/病理生理学脂肪酸类非酯化/血液脂肪酸类非酯化/代谢葡萄糖/代谢葡萄糖/治疗应用心脏传导系统/病理生理学胰岛素/治疗应用脂质移动心肌收缩心肌梗死/药物疗法心肌梗死/代谢心肌梗死/病理生理学心肌/代谢容积渗克分子浓度氧耗量副交感神经系统/病理生理学血浆容量氯化钾/治疗应用应激心理学动物人类

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Usefulness of ST elevation II/III ratio and ST deviation in lead I for identifying the culprit artery in inferior wall acute myocardial infarction

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AMERICAN JOURNAL OF CARDIOLOGY 2000年第3期86卷 341-+页

作者： Chia, BL Yip, JWL Tan, HC Lim, YT Natl Univ Hosp Dept Cardiac Singapore 119074 Singapore

In a study of 92 patients presenting with inferior wall acute myocardial infarction, the infarct-related artery was the right coronary artery in 72 patients (78%) and the left circumflex artery in 20 (22%). An ST II/III ratio of 1 or an isoelectric ST in lead I are sensitive and specific markers of left circumflex artery occlusion, whereas an ST II/III ratio <1 (ST elevation in lead III >II) or ST depression in lead I are sensitive and specific markers of right coronary artery occlusion.

关键词：冠状血管造影术冠状血管/病理生理学心电描记术心脏传导系统/病理生理学心肌梗死/诊断心肌梗死/病理生理学试验预期值成年人老年人女(雌)性人类男(雄)性中年人

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POSTEROSEPTAL ACCESSORY PATHWAYS - AN OVERVIEW OF ANATOMICAL CHARACTERISTICS, ELECTROCARDIOGRAPHIC PATTERNS, ELECTROPHYSIOLOGICAL FEATURES, AND ABLATIVE THERAPY

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JOURNAL OF INTERVENTIONAL CARDIOLOGY 1995年第1期8卷 89-101页

作者： JAZAYERI, MR DHALA, A DESHPANDE, S BLANCK, Z SRA, J AKHTAR, M WisconsinElectrophysiologyGroup UniversityofWisconsinMilwaukeeHeartInstituteofSinaiSamaritanMedicalCenterMilwaukee53233USA.

First, the posteroseptal region of the heart is probably the most complex area among those that harbor AV accessory fibers and a firm grasp of the anatomical characteristics of this region may facilitate achieving a successful AP ablation. Second, there is no sharp demarcation between the posteroseptal area and its surrounding regions including mid-septal, left posterior paraseptal, and right posterior paraseptal locations. Therefore, there are some inevitable overlaps between the electrocardiographic and electrophysiological features of APs located in the posteroseptal region and those areas immediately adjacent to it. Third, in the vast majority of cases, successful ablation can be achieved using a right atrial approach. Therefore, dividing posteroseptal APs into right- or left-sided pathways may only be useful for describing their ECG or electrophysiological characteristics with little or no value in predicting the site of successful ablation. Fourth, it seems advisable to attempt efforts to induce functional bundle branch block during orthodromic tachycardia and assess its effect on the VA interval. Ventriculoatrial interval prolongation due to right bundle branch block strongly favors a right free-wall or anteroseptal AP location. Prolongation of the VA interval by 30 msec or less in response to left bundle branch block is compatible with a posteroseptal location. In this situation, the mapping and ablative efforts should primarily be focused on the right atrial approach, including the terminal coronary sinus. If left bundle branch block causes VA interval lengthening of 30 msec or greater, the AP is most likely in the left free-wall region, including the posterior paraseptal area. Finally, the presence of APs having an intimate relationship with the middle cardiac (posterior interventricular) vein or the coronary sinus pouch, although exceedingly uncommon, should be considered in difficult cases in which radiofrequency applications to the conventional posteros

关键词：导管消融术心电描记术电生理学心脏传导系统/病理生理学心脏传导系统/外科学心间隔/病理生理学人类

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Radial approach: A new concept in surgical treatment for atrial fibrillation I. Concept, anatomic and physiologic bases and development of a procedure

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ANNALS OF THORACIC SURGERY 1999年第1期67卷 27-35页

作者： Nitta, T Lee, R Schuessler, RB Boineau, JP Cox, JL Washington Univ Sch Med Div Cardiothorac Surg St Louis MO 63110 USA Washington Univ Sch Med Div Cardiol St Louis MO 63110 USA

Background. The maze procedure cures atrial fibrillation;however, it isolates the pulmonary vein area and results in discordant activation in certain adjacent left atrial segments, which affects left atrial function. To preserve a more physiologic atrial transport function, we developed a new concept of surgical treatment for atrial fibrillation-the radial approach. The atrial incisions radiate from the sinus node toward the atrioventricular annular margins to allow a more physiologic atrial activation sequence and parallel the atrial coronary arteries to preserve blood supply to most atrial segments. Methods. We examined the atrial coronary arteries and the activation sequence during sinus rhythm in normal canine hearts to design the atrial incisions according to the concept of a radial approach. Results. The pattern of coronary artery distribution was centripetal, branching from the right coronary or left circumflex coronary artery at the right or left atrioventricular groove and spreading toward the sinus node. The endocardial mapping of the atria disclosed some important findings in designing the atrial incisions of the radial approach: the activation sequence at the left atrial septum and at the posterior left atrium between the pulmonary vein orifices. The atrial incisions were designed according to these findings. Conclusions. The radial approach may represent a more physiologic atrial transport function. (C) 1999 by The Society of Thoracic Surgeons.

关键词：心房颤动/病理生理学心房颤动/外科学心房功能心脏外科手术/方法心房/神经支配心脏传导系统/病理生理学动物狗女(雌)性人类男(雄)性

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Electrocardiographic predictive factors of long-term clinical improvement with multisite biventricular pacing in advanced heart failure

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AMERICAN JOURNAL OF CARDIOLOGY 1999年第12期84卷 1417-1421页

作者： Alonso, C Leclercq, C Victor, F Mansour, H de Place, C Pavin, D Carré, F Mabo, P Daubert, JC CHU Hop Pontchaillou Ctr Cardiopneumol Dept Cardiol & Malad Vasc F-35033 Rennes France

Biventricular pacing has recently been proposed for treating patients with drug refractory heart failure and intraventricular conduction delay. The purpose is to restore ventricular relaxation and contraction sequences as homogeneously as possible. The aim of this study was to determine if some factors could predict the long-term clinical effectiveness of that new treatment. This study included 26 patients, aged 66 +/- 7 years, with drug refractory heart failure and wide QRS. Patients were implanted with a biventricular pacemaker. The left ventricle was paced through a coronary sinus tributary. New York Heart Association functional class, exercise tolerance, and left ventricular (LV) ejection fraction were collected at baseline and after pacemaker implantation. Patients were divided into 2 groups: group I = responders;group II = nonresponders. QRS duration and axis at baseline and during biventricular pacing, interventricular conduction time, and LV and right ventricular lead positions were compared between the 2 groups. Group I patients (n = 19) had a mean reduction of 1.3 in functional class and an increase in peak oxygen consumption rate by a mean of 50%. The only parameter that differed between the 2 groups was the QRS duration during biventricular pacing, with, a significantly shorter value in group I than in group II (154 +/- 17 vs 177 +/- 26 ms;p = 0.016). Thus, a positive response to biventricular pacing is correlated with the quality of electrical resynchronization. The optimal positions of the right and LV leads would be those that could induce the greatest shortening of QRS duration. (C) 1999 by Excerpta Medica, Inc.

关键词：心电描记术运动试验心脏传导系统/病理生理学心室/病理生理学心肌收缩/生理学氧耗量/生理学心脏起搏器人工每搏输出量/生理学治疗结果老年人女(雌)性人类男(雄)性中年人

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