经球囊超声消融肺静脉口治疗阵发性心房颤动的临床研究

目的对经球囊超声消融肺静脉口治疗阵发性心房颤动的疗效和安全性进行临床评价。方法阵发性心房颤动患者5例，症状明显且应用抗心律失常药物治疗无效。经球囊超声消融肺静脉的开口，消融终点为肺静脉电学隔离。结果总计消融了19支肺静脉，单纯超声消融肺静脉实现电学隔离15支(73、7％)。早期有1例心房颤动复发，1例频发房性期前收缩，1例偶发房性期前收缩，均经胺碘酮治疗后消失。所有患者的随访时间超过6个月，均可以无需药物而维持窦性心律。并发症包括消融中1例出现心房穿孔，1例出现严重迷走反应，无肺静脉狭窄。结论肺静脉口超声消融是治疗阵发性心房颤动的一种有效手段。     

射频消融治疗心房颤动和心房扑动策略探讨

目的评价射频消融使肺静脉电解剖隔离和消除左房碎裂电位治疗心房颤动（简称房颤）的效果,进一步探讨与心房扑动（简称房扑）的关系。方法63例房颤患者分为两组,其中阵发性房颤32例,持续性房颤31例。在Ensite NavX三维标测系统下,建立左心房一肺静脉电解剖模型,分别对左、右肺静脉前庭大环状消融达完全左心房．肺静脉电解剖隔离,若房颤未终止或被诱发,再标测左心房内碎裂电位,消融碎裂电位;对22例合并典型房扑者行三尖瓣峡部消融。随访9个月观察影响手术复发的因素。结果所有患者均达左心房一肺静脉电解剖隔离。32例阵发性房颤患者中23例（71．9％）和31例持续性房颤患者8例（25．8％）经单纯肺静脉电隔离后房颤终止,不被诱发,两者相比有统计学意义（P〈0．01）;7例（21．8％）阵发性房颤和19例（61．3％）持续性房颤患者经联合消融左心房碎裂电位转复窦律,2例阵发性房颤和4例持续性房颤患者住院期间转复,术中总房颤即刻终止率两组相比较无统计学意义（P〉0．05）。阵发性房颤和持续性房颤患者消融成功率分别为84．4％和80．6％（P=0．697）,多元Logistic回归分析显示合并典型房扑是房颤术后复发的一个危险因素（P=0．007）。结论肺静脉电解剖隔离结合消除左心房碎裂电位是治疗房颤的一种有效策略,房颤和房扑的启动与维持可能存在一些共同机制。     

完全肺静脉电隔离在环肺静脉导管射频消融治疗阵发性心房颤动中的意义

目的:评价环肺静脉导管射频消融治疗阵发性心房颤动时以完全肺静脉电隔离作为消融终点的意义。方法:将83例有症状的阵发性房颤患者分为两组,在CARTO指导下,行环肺静脉的线型消融一组(CPVA Lasso组)43例,消融终点:肺静脉传入、传出阻滞,肺静脉完全电隔离。另一组(CPVA组)40例,消融终点为两侧环肺静脉消融线完整,局部双极电位振幅减低>80%或振幅<0.1 mv;随访3～6个月,对部分药物无效的复发房颤或房速的患者行第2次消融治疗,采用CPVA Lasso方案。结果:第1次消融结束后,两组患者经过3～6个月随访,CPVA组有24例(60%),CPVA Lasso组32例(74%),在停服抗心律失常药物后无房颤或房速的发作。对两组中20例药物无效的复发房颤或房速的患者行第2次消融手术,再次消融术中所有患者均采用CPVA Lasso方案,术后随访3～9个月,停服抗心律失常药物后,症状性房颤或房速不再发作者18例(90%)。结论:环肺静脉导管射频消融治疗有症状的阵发性房颤患者时,以完全肺静脉电隔离为消融终点可有效防止房颤的复发。     

三维电解剖标测系统结合肺静脉前庭电位指导心房颤动经导管消融

背景:目前常用的肺静脉前庭定位手段主要是通过三维电解剖标测(CARTO)结合X射线影像或CT影像融合等完成,这些方法均是通过解剖指导进行肿静脉前庭定位、消融,消融是否命中心房颤动(房颤)赖以维持的关键部位不得而知.目的:验证三维电解剖标测系统结合肺静脉前庭电位指导房颤经导管消融治疗的可行性.设计、时间及地点:验证性临床试验,于2007-03/2009-06在济南市第四医院及河北省人民医院心内科完成.对象:纳入药物治疗无效的症状性阵发性房颤患者51例.方法:于CARTO标测系统结合肺静脉前庭电位标测指导下行环肺静脉前庭线性消融,消融终点为肺静脉隔离,观察操作相关参数及消融成功率.主要观察指标:观察手术操作时间、X射线照射时间、手术成功率及并发症等操作相关参数.结果:51例患者均实现消融终点.平均操作时间(207±36.7)min,透视时间(38.2±14.3)min,消融时间(56.4±15.7)min.经过(17.5±3.8)个月的随访,累计40例(78.4%)无房颤、心房扑动及房性心动过速等心律失常发生.无严重操作相关并发症发生.结论:肺静脉前庭电位标测有助于肺静脉前庭的解剖定位,结合三维电解剖系统指导房颤消融效果好,安全性高,方法可行.     

Ensite NavX系统指导阵发性心房纤颤的射频消融治疗

目的评价Ensite NavX系统指导下射频消融治疗阵发性心房纤颤(房颤)的疗效。方法6例反复发作阵发性房颤患者,术中采用Ensite NavX系统结合肺静脉造影建立左心房及肺静脉模型,并定位出左右肺静脉前庭开口及其周围呈现双电位或复合高频电位的靶点位,在环状电极的标测下,分别沿左右肺静脉前庭开口进行环状消融,并消融其周围双电位及复合高频电位处,直至双侧肺静脉内电位完全隔离。结果6例病人术后即刻均达到完全肺静脉内电位隔离。其中1例术中完全隔离肺静脉电位后,房颤仍发作,然后进行左心房顶及两肺静脉前庭之间线状消融后,房颤转为不纯性心房扑动(房扑),再行右心房峡部消融,房扑转为房速,在上腔静脉内标测到激动最为提前的靶点,消融成功,心律转为窦性心律。所有病人术中均无并发症发生。6例患者术后随访均未有阵发性心悸发作。2例术前伴有窦房结功能障碍的病人未发现窦房结功能异常。结论在Ensite NavX系统指导下的肺静脉前庭环状消融治疗阵发性房颤安全、有效,因操作的复杂性,应在有经验的中心进行。     

三维电解剖标测系统与CT影像融合指导心房颤动导管消融

背景:目前通常采用的肺静脉前庭定位方法主要有三维电解剖标测系统指导(CARTO)或与CT/核磁共振影像融合定位(CARTO-Merge)两种方法.理论上讲CARTO-Merge技术提供了更多的解剖细节,导航精确度更高,但其是否有利于提高房颤导管消融治疗的成功率及安全性仍有待临床观察评价.目的:验证三维电解剖标测系统联合CT影像融合在指导房颤导管消融中的作用.设计、时间及地点:对比观察,于2005-10/2007-05在首都医科大学附属北京安贞医院心内科完成.对象:选择进行环肺静脉前庭线性消融治疗的阵发性房颤患者93例.方法:试验分为2组,CARTO组50例,CARTO-Merge组43例,分别于CARTO系统及CARTO-Merge指导下行环肺静脉前庭线性消融,消融终点为肺静脉隔离.主要观察指标:比较两组操作时间,X射线照射时间,手术成功率及并发症等情况.结果:所有患者均实现消融终点,随访时间(12.6±2.9)个月,73例(78.5%)患者消融后3个月无房性心律失常复发.CARTO组X射线照射时间显著长于CARTO-Merge组(P<0.05),两组操作时间、消融时间、消融成功率及并发症比较差异无显著性意义(P>0.05).结论:采用单纯CARTO或联合CT影像融合技术指导的环肺静脉前庭消融均具有良好的临床疗效和安全性.但CT影像融合技术可更清楚展示心脏解剖,有利于肺静脉的准确定位,并显著缩短X射线透视时间.     

超声消融电隔离肺静脉治疗阵发性心房颤动9例

目的　利用美国IBI公司生产的超声消融球囊导管和超声消融发生仪治疗和随访阵发性心房颤动 9例 ,观察疗效和并发症。方法　 9例患者中男性 5例 ,女性 4例 ,平均年龄 (5 4 4± 5 2 )岁。其中 1例为轻度高血压患者 ,其余无明显器质性心血管病病史。阵发性心房颤动病史平均为 (4 3± 3 7)年。全部患者房颤发作频率在每月 3次或以上。经穿间隔卵圆窝置入左 1号Swartz鞘 ,经Swartz鞘送入头端可控大头电极分别送至不同肺静脉 ,直接用大头电极标侧肺静脉肌袖电位或换用A focus电极标侧 ,对存在肌袖电位的肺静脉行超声消融。功率一般为 35～ 4 0瓦 ,温度为 6 0℃ ,每次消融时间为 12 0秒 ,重复至肺静脉电位被隔离或消失 ,但同一肺静脉重复消融不超过 10次。结果　本组完全成功脱离药物治疗 3例 ,发作次数明显减少或少量药物能够维持不发作 2例 ,有 2例完全无效 ,另 2例需要进一步随访。结论　超声消融肺静脉电隔离治疗阵发性心房颤动 ,本组成功率和有效率超过 5 0 % ,无肺静脉狭窄等并发症。     

心房颤动射频消融术中异丙酚复合静脉麻醉的护理

心房颤动（房颤）是临床上最常见的心律失常类型之一，人群中总患病率0．5％～1％。近年来，随着对房颤发病机制的进一步认识，应用射频能量进行环肺静脉线性电学隔离消融术成为治疗房颤的经典方法。但射频放电时患者常有剧烈疼痛，甚至不能忍受，影响患者的依从性和手术的效果。2008年5月起我们在心房颤动患者行环肺静脉线性电学隔离消融术中采用异丙酚复合静脉麻醉方法来缓解患者疼痛，在充分的术前准备，术中观察与护理下取得良好的效果，现将护理体会报道如下。     

Ensite NavX三维标测系统加单Lasso电极指导环肺静脉左心房线性导管射频消融治疗心房颤动

近年来随着心房颤动（房颤）导管射频消融技术的成熟和器械的完善,使用Carto、Ensite NavX三维电解剖标测指导下环肺静脉左心房线性消融成为治疗房颤的主要方法之一^[1-2]。Ouyang等^[3-4]首先采用双Lasso导管放置在同侧肺静脉内,以左心房和肺静脉口的完全隔离为环肺静脉线性消融的终点,取得了满意疗效,但操作复杂,费用昂贵。     

经心外膜聚焦超声消融治疗犬心房颤动的实验研究

目的 探讨聚焦超声经心外膜的环肺静脉消融(CPVa)和左房盒式消融(BOXa)对房颤的影响.方法 成年杂种犬20只,随机分为两组,建立肺静脉起源的阵发性房颤模型后,直视下分别行环肺静脉消融和左房盒式消融.消融前、后记录左房有效不应期(LA-ERP)、计算房颤诱发率、记录房颤持续时间,术毕行组织学检查.结果 所有犬均能诱发出肺静脉起源的阵发性房颤,房颤终止后的LA-ERP较基线水平显著缩短[CPVa组:(140±10)ms vs(102±10)ms,P＜0.01;BOXa组:(139±11)ms vs(105±8)ms,P＜0.01],但消融前后的LA-ERP并无显著性差异[CPVa组:(102±10)ms vs(110 8)ms,P=0.070;BOXa组:(106±7)ms vs(111±7)ms,P=0.225].消融后两组的房颤诱发率均较消融前显著降低[(98±4)%vs(28±10)%,P＜0.01,(97±4)%vs(14±7)%,P＜0.01],房颤持续时间均显著缩短[(233±40)s vs(70±29)s,P＜0.01;(240±41)s vs(34±22)s,P＜0.01];部分犬可见肺静脉一心房双向电传导阻滞;两组间消融前房颤诱发率、房颤持续时间无统计学差别,消融后BOXa组房颤诱发率和房颤持续时间低于/短于CPVa组(P＜0.05).消融后焦域内的组织呈凝固性坏死.结论 经心外膜聚焦超声环肺静脉消融可显著降低房颤诱发率和缩短房颤持续时间,而左房盒式消融则可进一步提高成功率.     

Determination of creatine kinase isoenzyme MB activity in serum using immunological inhibition of creatine kinase M subunit activity. Activity kinetics and diagnostic significance in myocardial infarction.

This is a new method for the determination of creatine kinase isoenzyme MB activity in serum. The method uses direct activity measurement of creatine kinase B subunit activity after blocking of CK-M subunit activity by inhibiting antibodies. The test takes no longer than 15 min. The method yields an intra-serial C.V. of 2.0-12.9%, and a C.V. from day to day of 5.5%. The detection limit is 3.4 U/l creatine kinase MB. In the 95 cases with proven myocardial infarction several types of creatine kinase MB activity kinetics could be determined. The percentage of creatine kinase MB of peak CK-total is 6-25%, with a mean of 11.1%. The amount of creatine kinase MB with respect to total CK activity after reinfarction is higher than the amount after initial infarction.     

Dissociable correlates of two classes of retrieval processing in prefrontal cortex

Although substantial evidence suggests that the prefrontal cortex (PFC) implements processes that are critical for accurate episodic memory judgments, the specific roles of different PFC subregions remain unclear. Here, we used event-related functional magnetic resonance imaging to distinguish between prefrontal activity related to operations that (1) influence processing of retrieval cues based on current task demands, or (2) are involved in monitoring the outputs of retrieval. Fourteen participants studied auditory words spoken by a male or female speaker and completed memory tests in which the stimuli were unstudied foil words and studied words spoken by either the same speaker at study, or the alternate speaker. On "general" test trials, participants were to determine whether each word was studied, regardless of the voice of the speaker, whereas on "specific" test trials, participants were to additionally distinguish between studied words that were spoken in the same voice or a different voice at study. Thus, on specific test trials, participants were explicitly required to attend to voice information in order to evaluate each test item. Anterior (right BA 10), dorsolateral prefrontal (right BA 46), and inferior frontal (bilateral BA 47/12) regions were more active during specific than during general trials. Activation in anterior and dorsolateral PFC was enhanced during specific test trials even in response to unstudied items, suggesting that activation in these regions was related to the differential processing of retrieval cues in the two tasks. In contrast, differences between specific and general test trials in inferior frontal regions (bilateral BA 47/12) were seen only for studied items, suggesting a role for these regions in post-retrieval monitoring processes. Results from this study are consistent with the idea that different PFC subregions implement distinct, but complementary processes that collectively support accurate episodic memory judgments.     

俯卧位通气对高海拔地区肺复张治疗无效急性呼吸窘迫综合征患者氧合的影响

目的 探讨俯卧位通气对高海拔地区肺复张术(RM)治疗无效急性呼吸窘迫综合征(ARDS)患者的治疗作用.方法 从海拔2260m的地区医院筛选RM治疗无效的41例ARDS患者[平均氧合指数( PaO2/FiO2)较RM前升高＜20％视为RM无效],依不同病因分为肺内源性ARDS组(ARDSp组)和肺外源性ARDS组(ARDSexp组),每组再按信封法随机分为俯卧位组和仰卧位组,即ARDSp俯卧位组(11例)、ARDSp仰卧位组(9例)、ARDSexp俯卧位组(10例)、ARDSexp仰卧位组(11例).在通气前及通气1、2、3、4h监测动脉血氧分压( PaO2)、PaO2/FiO2、静态顺应性(Cst)、气道阻力(Raw)的变化.结果 通气lh时,ARDSexp俯卧位组PaO2/FiO2( mm Hg,l mm Hg=0.133 kPa)即较通气前显著升高(157.4±40.6比129.3±48.7,P＜0.05),并随通气时间延长呈持续增高趋势,4h达峰值(219.1 ±41.1);且ARDSexp俯卧位组通气3h内PaO2/FiO2较其他3组显著增高,另3组间则差异无统计学意义.ARDSp俯卧位组、ARDSexp俯卧位组通气4h时PaO2/FiO2均较相应仰卧位组显著增高(208.8±39.7比127.4±47.1,219.1±41.1比124.9±50.8,均P＜0.05).4组通气前后Cst无显著改变,各组间差异也无统计学意义.ARDSp俯卧位组通气4h时Raw(cmH2O·L-1·s-1)较通气前显著降低(6.8±1.7比10.7±1.8,P＜0.05),且明显低于其他3组;其他3组各时间点Raw组内及组间比较差异均无统计学意义.结论 俯卧位通气作为ARDS机械通气重要策略之一,可以改善RM无效高原ARDS患者的氧合,为抢救患者赢得宝贵的时间.     

Digital imaging among medical facilities

The Department of Veterans Affairs (VA) in the USA operates a network of 172 medical centres which all utilize a hospital information system (HIS) which has been developed and is currently maintained by the VA. During the past several years, an image management and communication module has been developed, installed and clinically utilized at the Washington DC and Maryland VA Medical Centres. This image management and communication system, referred to as the decentralized hospital computer program (DHCP) imaging system, is fully integrated with a commercial picture archiving and communication system (PACS). The system is utilized to capture, archive, and display all images generated within the hospital including radiology, nuclear medicine, pathology, endoscopy, bronchoscopy, and dermatology, intraoperative photographs, ECG data, and a limited number of paper documents. The ultimate goal of the project is to have all patient text and image data available at any clinical workstation to any authorized user anywhere within the network of medical centres. Clinical requirements for an imaging workstation include ease of use, rapid and reliable access to the complete set of patient information, and images which are of acceptable quality to meet the requirements of the user and the subspecialty. Patient confidentiality and data security must be safeguarded at all times. Integration of the images with the remainder of the patient's database was found to be critical to the success of the project. The experience at the Washington and Maryland facilities suggests that an imaging system that is successfully integrated with a hospital information system can provide substantial clinical and economic benefits both within and among medical centres. Clinical acceptance and utilization of the system has been excellent, particularly in diagnostic radiology where DHCP Imaging has been interfaced to a commercial PAC system. Based upon this initial experience, the VA has begun to deploy the system throughout its large network of medical centres.     

Myocardial elastography at both high temporal and spatial resolution for the detection of infarcts

Myocardial elastography is a novel method for noninvasively assessing regional myocardial function, with the advantages of high spatial and temporal resolution and high signal-to-noise ratio (SNR). In this paper, in-vivo experiments were performed in anesthetized normal and infarcted mice (one day after left anterior descending coronary artery [LAD] ligation) using a high-resolution (30 MHz) ultrasound system (Vevo 770, VisualSonics Inc., Toronto, ON, Canada). Radiofrequency (RF) signals of the left ventricle (LV) in longitudinal (long-axis) view and the associated electrocardiogram (ECG) were simultaneously acquired. Using a retrospective ECG gating technique, 2-D full field-of-view RF frames were acquired at an extremely high frame rate (8 kHz) that resulted in high-quality incremental displacement and strain estimation of the myocardium. The incremental results were further accumulated to obtain the cumulative displacements and strains. Two-dimensional and M-mode displacement images and strain images (elastograms), as well as displacement and strain profiles as a function of time, were compared between normal and infarcted mice. Incremental results clearly depicted cardiac events including LV contraction, LV relaxation and isovolumetric phases in both normal and infarcted mice, and also evidently indicated reduced motion and deformation in the infarcted myocardium. The elastograms indicated that the infarcted regions underwent thinning during systole rather than thickening, as in the normal case. The cumulative elastograms were found to have higher elastographic SNR (SNR(e)) than the incremental elastograms (e.g., 10.6 vs. 4.7 in a normal myocardium, and 6.0 vs. 2.4 in an infarcted myocardium). Finally, preliminary statistical results from nine normal (m = 9) and seven infarcted (n = 7) mice indicated the capability of the cumulative strain in differentiating infracted from normal myocardia. In conclusion, myocardial elastography could provide regional strain information at simultaneously high temporal (>/=0.125 ms) and spatial ( approximately 55 microm) resolution as well as high precision ( approximately 0.05 microm displacement). This technique was thus capable of accurately characterizing normal myocardial function throughout an entire cardiac cycle, at the same high resolution, and detecting and localizing myocardial infarction in vivo.     

Clinical Pharmacokinetics of Morphine

Morphine, the most widely used mu-opioid analgesic for acute and chronic pain, is the standard against which new analgesics are measured. A thorough understanding of the pharmacokinetics of morphine is required in order to safely and effectively use this analgesic in a wide variety of patients with different levels of organ function. A MEDLINE search was conducted to identify literature published between 1966 and January 2002 relevant to the pharmacokinetics of morphine. These publications were reviewed and the literature summarized regarding unique and clinically important elements of morphine disposition relative to its parenteral administration (including intravenous, intramuscular, subcutaneous, epidural and intrathecal administration), absorption profile (immediate release, controlled release, and sublingual/buccal, and rectal administration), distribution, and its metabolism/ excretion. Special populations, including infants, elderly, and those with renal/liver failure, have a unique morphine pharmacokinetic profile that must be taken into account in order to maximize analgesic efficacy and reduce the risk of adverse events.