彩色多普勒超声心动图在合并肺动脉高压先天性心脏病封堵术中的应用

目的 探讨彩色多普勒超声心动图在先天性心脏病合并肺动脉高压(PH)封堵术中的应用价值.方法 209例伴有PH的先天性心脏病患者在超声全程临测下实施封堵治疗,其中房间隔缺损(ASD)86例,室间隔缺损(VSD)17例,动脉导管未闭(PDA)106例,超声心动图观察肺动脉收缩压(PASP)有无降低及降低的程度.结果 试封堵30～60 min后,合并轻度PH的136例患者PASP均降至正常;中度PH的46例中30例PASP降至正常,16例降至轻度;重度PH的17例中9例PASP降至中度,6例PASP下降≥30 mm Hg.以上患者均行永久性封堵治疗.2例重度PH患者PASP无明显变化,为阻力性PH,未行封堵治疗.结论 彩色多普勒超声心动图可在伴有PH的先天性心脏病封堵术前、术中及术后评估PASP的变化.     

彩色多普勒超声诊断动脉导管未闭并肺动脉高压46例分析

目的：探讨应用彩色多普勒超声诊断动脉导管未闭的方法。方法：对临床疑诊动脉导管未闭的46例患者进行超声心动图检测,应用二维、彩色及频谱多普勒超声重点观察肺动脉长轴分叉部及主动脉弓降部检测导管情况。结果：有45例符合动脉导管未闭的超声影像学诊断,1例漏诊。其中合并有肺动脉高压13例。结论：多普勒超声心动图诊断动脉导管未闭具有无痛、无创、方便、诊断率高等优点,并有助于评价肺动脉高压的程度,应是影像学诊断的首选方法。     

彩色多普勒超声心动图在小儿先天性肺动脉吊带诊断中的应用

目的探讨彩色多普勒超声心动图在先天性肺动脉吊带诊断中的应用价值。方法以CT血管成像（CTA）和手术证实的12例肺动脉吊带患儿为研究对象,回顾分析其彩色多普勒超声心动图特征。结果12例肺动脉吊带患儿经超声心动图检查确诊10例,漏诊2例。诊断正确率为83％。超声心动图显示肺动脉分叉消失,主肺动脉直接延续为右肺动脉,于右肺动脉发出异常起源的左肺动脉。2例漏诊患儿中1例是肺动脉吊带合并动脉导管未闭,超声心动图仅诊断出动脉导管未闭;另一例为单纯性肺动脉吊带,因超声医师对本病的认识不足,未做出肺动脉吊带的诊断,后行CTA检查,提示肺动脉吊带。结论彩色多普勒超声心动图可在早期对肺动脉吊带作出诊断,常规行彩色多普勒超声心动图检查时,应注意肺动脉分叉处左肺动脉的位置是否异常,多切面检查,减少对本病的漏诊误诊。     

彩色多普勒超声在扩展先天性室间隔缺损合并重度肺动脉高压患者手术适应证中的研究

目的 彩色多普勒超声在扩展先天性室间隔缺损(VSD)合并重度肺动脉高压(PH)患者手术适应证中的应用价值.方法 选取先天性VSD并重度PH患者30例,肘静脉注射腺苷75 μg·kg-1·min-1,应用彩色多普勒超声心动图检测主动脉平均压、肺动脉平均压、肺动脉收缩压、肺动脉舒张压、肺循环阻力、体循环阻力、肺循环阻力/体循环阻力比值、肺动脉/主动脉收缩压比值、肺循环/体循环血流量比值,注射5分钟后肺血管阻力下降>30%和肺动脉平均压下降>10%为急性血管扩张试验阳性.结果 17例急性血管扩张试验阳性者,通过临床药物降压治疗有效后成功手术;13例药物试验阴性者继续降压治疗无效.结论 通过腺苷急性血管扩张试验,可以判断肺动脉高压的可逆性,彩色多普勒超声心动图在扩展先天性室间隔缺损合并重度肺动脉高压患者手术适应征中起到初步筛选的作用.     

肺动脉吊带的彩色多普勒超声心动图诊断价值

目的探讨彩色多普勒超声心动图对肺动脉吊带早期诊断的价值。方法以CT血管成像(CTA)和手术证实的5例肺动脉吊带患儿为研究对象,回顾分析其病因及超声心动图特征。结果肺动脉吊带患儿5例,超声诊断4例,诊断正确率80%(4/5),漏诊1例,漏诊率20%(1/5),其中1例合并房间隔缺损,2例合并永存左上腔静脉。结论超声心动图可早期诊断肺动脉吊带,常规行超声心动图检查时,应注意左肺动脉的位置是否异常,对提高该病早期诊断率具有重要的临床价值。     

右心超声造影在动脉导管未闭合并重度肺动脉高压诊断中的应用价值

动脉导管未闭（PDA）是一种常见的器质性先天性心脏病。目前，主要依据超声心动图确诊。虽然超声心动图能明确大部分的PDA，然而当PDA合并重度肺动脉高压时，掩盖了PDA的特殊心音及超声表现；超声心动图极易误诊为原发性肺动脉高压。本文拟对这类患者的超声诊断加以总结分析。     

超声心动图对肺动脉闭锁伴室间隔缺损的评价

目的应用二维超声心动图结合彩色多普勒评价肺动脉闭锁伴室间隔缺损及肺动脉血供情况。方法2003～2004年期间用超声心动图和彩色多普勒对22例年龄15h～7岁(平均347d)的儿童肺动脉闭锁伴室间隔缺损以及肺动脉血供进行了研究。结果22例肺动脉闭锁的患儿全部合并室间隔缺损，14例未闭动脉导管(PDA)，为肺动脉供血来源。6例体肺侧支动脉通道，其中3例合并小的PDA。2例既未探测到PDA又未发现体肺侧支动脉。所有PDA患儿均见到肺动脉融合部。彩色多普勒能精确地检测到有无侧支血管和供血起源，6例有体肺侧支、肺动脉融合的患儿中，5例(85％)可见到逆向血流。3例未能发现肺动脉主干。结论超声心动图结合彩色多普勒对新生儿和儿童肺动脉闭锁合并室间隔缺损的肺动脉血供有重要诊断价值。     

先天性主动脉缩窄的超声诊断价值

目的探讨二维及彩色多普勒超声心动图对先天性主动脉缩窄(CoA)的诊断价值。方法回顾性分析35例CoA患者的二维及多普勒超声表现,并与手术结果作对照。结果35例患者均经手术证实为CoA,其中超声检出31例,1例被误诊为主动脉弓离断,3例漏诊;3例为单发CoA,32例均合并有室间隔缺损(VSD,18例)或动脉导管未闭(PDA,19例)或二者兼存或其他畸形;11例伴有肺动脉高压;1例伴有感染性心内膜炎。结论超声心动图检查是诊断CoA及其他合并畸形的有效方法,具有无创、快速、准确性较高的优点,可作为首选方法;胸骨上窝声窗的常规检查有助于避免漏诊。     

超声心动图对主肺动脉间隔缺损的诊断价值探讨

目的分析主肺动脉间隔缺损(APSD)的超声心动图特征,探讨超声心动图对APSD的诊断价值。方法回顾性分析经心导管及手术结果证实的49例APSD患者的超声心动图资料,总结其特征,包括APSD分型、部位、大小、房室大小、分流情况,以及是否合并其他心脏畸形情况。结果①49例患者中,术前超声准确诊断APSD 45例,漏诊4例,诊断准确率91.8%。②超声心动图诊断Ⅰ型11例(22.4%),Ⅱ型24例(49.0%),Ⅲ型14例(28.6%),其中45例分型与经心导管及手术结果相符。③二维超声心动图表现为主肺动脉间隔连续性中断,缺损范围约5～50mm。左心系统增大22例(44.9%),右心系统增大4例(8.2%),全心扩大(左心为著)21例(42.9%),右室壁增厚4例(8.2%),主动脉、肺动脉内径均增宽,以肺动脉内径增宽为著。彩色多普勒超声表现为左向右分流12例(26.7%),双向分流25例(55.6%),右向左分流8例(17.7%)。轻度肺动脉高压3例(6.1%),中度肺动脉高压10例(20.4%),重度肺动脉高压36例(73.5%)。结论超声心动图是诊断APSD的有效方法,能在术前对其进行详细评估,有助于临床制定治疗方案,具有较好的应用价值。     

超声心动图诊断先天性矫正型大动脉转位的价值

目的探讨超声心动图对先天性矫正型大动脉转位(ccTGA)的诊断价值。方法回顾性分析43例先天性矫正型大动脉转位超声心动图二维图像、彩色多普勒声像图表现并与心脏磁共振、心血管造影及手术结果对比分析,总结其诊断特点,找出漏诊的原因。结果术前确诊41例,漏诊2例;左位心36例,中位心3例,右位心3例;SLL型(心房正位,心室左袢,主动脉位于肺动脉左前)32例。SLD型(心房正位,心室左袢,主动脉位于肺动脉右前)5例。IDD型(心房反位,心室右袢,主动脉位于肺动脉右前)3例。IDL型(心房反位,心室右袢,主动脉位于肺动脉左前)3例;合并的畸形:室间隔缺损28例,肺动脉瓣或瓣下狭窄15例,三尖瓣发育异常24例(2例合并Ebstein畸形),房间隔缺损或卵圆孔未闭10例,动脉导管未闭5例,右心室双出口2例;漏诊2例为成人诊断为二尖瓣发育畸形,重度二尖瓣反流;41例超声诊断与心脏磁共振、心血管造影及手术结果一致。结论超声心动图诊断先天性矫正型大动脉转位具有较高的准确度,在成人重度二尖瓣反流中,应除外ccTGA。     

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.