56例短阵室性心动过速分析

经动态心电图确诊的短阵室速56例中早搏型短阵室速频率较快,面并行型与定性自主节律增高型较慢;经测定绝大部分短阵室速的提前指数>1,而易损指数<1.4.因此,一般不会引起室颤.56例经1--3年随访,短阵速室绝大部分自行消失,未见引起阿-斯综合征发作或死亡。     

左室特发性室速的新的分类方法及电生理特点

特发性室速指无器质性心脏病的室性心动过速 ,通常分成特发性左室室速和特发性右室流出道室速两种。其中特发性左室室速 (ＩＬＶＴ)约占特发性室速的 2 0 % ,多见 15～ 4 0岁的患者 ,男性多见 ,约占6 0 %～ 80 %。室速频率多在 140～ 2 2 0次 /分之间。室速发作时病人可有心悸、眩晕、先兆晕厥和晕厥等症状[1] ,但多数患者发作时的血流动力学仍稳定。无休止性ＩＬＶＴ可引起心律失常性心肌病。ＩＬＶＴ是指不伴有器质性心脏病、发生在左室左后分支内的折返性室速。近年来 ,随着临床心脏电生理学的发展以及室速射频消融技术的进展 ,对特发性…     

室性心动过速的周期重整和拖带

室性心动过速(室速)引进的期前刺激,引起不完全代偿间歇后,原来的室速继续发生,这就是持续性室速发生了周期重整(resetting)。继续发生亦即重新开始的室速,其第1个QRS的形态和周期长度(周长)都必须与释出期前刺激前的室速相同,不论所用的期前刺激是单个或多个。这段不完全性代偿间歇称为回复周期(return cycle)。     

与室速有关的心电学指标分析

目的利用动态心电图检测发生在室速前的有关心电学指标,旨在探讨参与室速的心电因素.方法动态心电图中持续性室速或非持续性室速31例,分别测定室速前10次窦性心动周期、QT间期、校正QT间期(QTc)及心率,与动态心电图中某一时段发生最少室早作比较,同时分析室早指数.结果与无室速时①qT间期比较,有显著统计学意义(t=3.86,P＜0.01).②QTc的变异度显著大于元室速时的变异度.③心率的比较未见有统计学意义(t=0.09,P＞0.05).④室早指数作为一种判定易否引起室速或室颤,实用价值显示不出.结论交感神经张力的增加与心室复极的不稳定因素参与了室速的形成.     

经食管心房起搏终止室性心动过速22例临床分析

经食管心房起搏常用于室上性心动过速（室上速）的诊断和治疗，而用于终止室性心动过速（室速）则报道较少。从理论上讲，如室上性冲动能夺获心室或采用超速起搏抑制均有可能打断折返环进而终止室速。虽终止室速的成功率远不及室上速，但若成功则病人免受直流电击之苦，且该方法简便、易行。为此，本期特刊出马红梅等撰写的文章，较为详尽地介绍了采用该法的适应证、具体方法及其效果，以期引起关注，共同探讨。[编者按]     

双向性室性心动过速

1922年,Schwensen首次报道1例洋地黄中毒患者伴有双向性室性心动过速(bidirectional ventriculartachycardia)。因此,双向性室速的概念并不陌生,近年来发现双向性室速也是家族遗传性儿茶酚胺敏感性室速(CPVT)患者的特征性心电图表现。[心电图特点]“双向性室速”这一心电学术语     

异常J波和多形性室速

近年来,几组原因不明而均伴有直立J波、反复发作多形性室速甚或导致猝死的病例报道,使人们对体表心电图的J波及其临床意义,尤其是J波和多形性室速等致命性室性心律失常的关系,重新引起重视。本文就此作一简述。     

对室性心律失常的认识及药物治疗现状

室性心律失常包括室性早搏(室早)，室性心动过速(室速)，心室扑动(室颤)及心室颤动(室颤)。持续时间少于30秒的室速称非持续性室速，超过30秒称持续性室速，有时需电击终止。按室速形态可分为单形性及多形性室速。室性心律失常常发生在有器质性心脏病的患者，但也可以发生在正常人、水一电解质和(或)酸碱平衡紊乱以及应用某些药物时。室性心律失常的发生机制有折返激动(微折返及大折返)及自律性异常     

右室室性心动过速的射频消融及其随访结果

目的观察右室室性心动过速(简称室速)射频消融的近、远期疗效。方法34例右室室速患者经受了射频消融，其中诊断为特发性右室室速29例，致心律失常性右室发育不全(ARVD)5例。结果28例特发性右室室速消融成功，1例失败；5例ARVD患者诱发出9种室速，5种室速消融成功，另4种室速失败。随访显示，28倒特发性右室室速中2例分别于射频消融术后的12和15个月发生新的室性心律失常，进一步检查证实1例为ARVD，另1例为扩张型心肌病。ARVD患者组中2例室速复发。结论右室室速射频消融的结果取决于有无器质性心脏病，对于特发性右室室速消融术后再发或出现新的室性心律失常患者，需注意排除ARVD或心肌病等器质性心脏病的存在。     

对于药物性尖端扭转型室速机制认识的新进展

近年研究提示,尖端扭转型室速可由心动过缓依赖性早期后除极和触发活动引起。ⅠA类和Ⅲ类抗心律失常药可引起二类促发活动,两者的频率分布不同。现有证据说明促发活动起源于浦肯野系统。细胞水平研究和单相动作电位记录共同表明早期后除极参与尖端扭转型室速的形成。     

Idiopathic verapamil-sensitive left ventricular tachycardia complicated by right ventricular outflow tract ventricular tachycardia and ventricular fibrillation.

Idiopathic ventricular tachycardias (VTs) are generally divided into those arising from the right ventricle and those arising from the left ventricle. There has been few reports of two morphologically distinct VT occurring in patients with no apparent structural heart disease. We report a patient with verapamil-sensitive left VT with a right bundle branch block pattern that spontaneously changed to VT with a left bundle branch block pattern. Ventricular fibrillation was induced by the application of programmed stimulation. Although it is unclear if our patient with pleomorphic VT has ventricular vulnerability, it is necessary to investigate further and follow him carefully.     

Isolated left ventricular noncompaction mimicking ventricular mass

Isolated left ventricular noncompaction is an inherited cardiomyopathy characterized by multiple prominent trabeculations with deep intertrabecular recesses. The diagnosis is often missed because echocardiography poses inherent problems of poor echo window in assessment of the LV apex, which is most commonly involved in noncompaction. We report a case in which conventional 2D echocardiography failed to demonstrate multiple prominent trabeculations. Contrast echocardiography confirmed the presence of multiple trabeculations with deep intertrabecular recesses. This report emphasizes the importance of contrast echocardiography in the diagnosis of ventricular noncompaction.     

Congenital ventricular diverticulum associated with ventricular tachycardia

Congenital ventricular diverticula are rare. Clinically, they may be asymptomatic or cause systemic embolization, heart failure, valvular regurgitation, ventricular rupture, ventricular arrhythmia, or sudden death. We report the case of a 56-year-old woman with sustained ventricular tachycardia, who, during investigation, was diagnosed with a diverticulum in the inferobasal portion of the left ventricle. The clinical characteristics and treatment of this rare disease are discussed.     

Direct mechanical ventricular assistance during ventricular fibrillation

A technique of direct mechanical ventricular assistance (DMVA) has been available since 1966. Ventricular assistance is provided by a glass cup lined with a Silastic diaphragm. It is held on the cardiac ventricles by suction. Alternating positive and negative pressure in the space between the cup and the diaphragm provides a pumping mechanism for blood flow. DMVA was compared to closed chest massage (CCM) and open chest massage (OCM) during ventricular fibrillation in six dogs. Each technique was applied for 10 minutes. Three dogs had CCM followed by OCM and then DMVA. Three dogs had only OCM and DMVA. Blood pressure and cardiac output were measured. All variables were calculated as a percentage of pre-ventricular-fibrillation values. Mean blood pressure was 19.7% with CCM, 39.8% with OCM, and 55.1% with DMVA. Systolic blood pressure was 25.8% with CCM, 51.9% with OCM, and 64.0% with DMVA. Diastolic blood pressure was 17.3% with CCM, 37.3% with OCM, and 48.9% with DMVA. Cardiac output was 13.8% with CCM, 37.1% with OCM, and 58.0% with DMVA. For each variable, OCM produced statistically higher values than did CCM. DMVA produced statistically higher values than did OCM for all variables. These preliminary results suggest that DMVA may be superior to currently available methods of cardiac massage during ventricular fibrillation.