MCE-NSS系统自动定量分析缺血再灌注大鼠存活心肌

目的 探讨基于中智相似积分（NSS）算法的心肌超声造影（MCE）分析系统自动定量评估缺血再灌注大鼠存活心肌的准确性及应用价值。 方法SD大鼠制成心肌缺血再灌注(I/R)模型，随机分为缺血30min再灌注组（I/R-30组）与缺血45min再灌注组（I/R-45组）。分别于术前、阻断即刻、再灌注后7d、14d及28d行心肌超声造影（MCE）获取左室短轴（乳头肌水平）切面图像，运用MCE-NSS系统自动勾勒心内膜及心外膜边界，并将心肌均分为18个节段，获得各心肌节段室壁增厚率（WT）及标化造影剂灌注强度（CI）值。阻断即刻，将室壁收缩运动减弱或消失节段（WT＜0.3）定义为危险节段；再灌注后危险节段被划分为三个区域：①WT<0.3且CI＜-54 Pix为危险中央区；②WT<0.3且CI＞-54Pix为危险周边区域；③WT>0.3且CI>-54Pix为危险恢复区；观察阻断即刻、术后7d、14d和28d时中央区、周边区和恢复区面积变化情况。术后28d取大鼠心脏，行Masson染色及免疫组化分别计算梗死面积和微血管密度，并与MCE-NSS系统测得的梗死面积行相关性分析。结果 ①危险节段各区域面积变化：术后7d、14d和28d时，两组危险中央区面积百分比变化较阻断即刻变化不明显（P＞0.05），而危险周边区面积逐渐减小（P＜0.01），危险恢复区面积逐渐增加（P＜0.01）；I/R-45min组危险中央区面积在各时间点均大于I/R-30min组（P＜0.01），危险周边区和危险恢复区面积在两组间比较差异无统计学意义（P＞0.05）；②与病理结果比较：危险中央区面积和Masson染色计算的梗死面积呈正相关（r=0.81, P＜0.01），危险周边区CI值与免疫组化计算的微血管密度呈正相关（r=0.86, P＜0.01）。 结论 新型MCE-NSS系统可以实现对心肌缺血再灌注后左室局部收缩功能及微循环情况的评估，并能识别存活心肌。     

无创心肌做功评估经皮冠状动脉介入治疗后急性ST段抬高型心肌梗死患者心肌节段微血管灌注

目的 观察无创心肌做功（MW）评估经皮冠状动脉介入治疗（PCI）后急性ST段抬高型心肌梗死（STEMI）患者心肌节段微血管灌注（MVP）的效能。方法 分析119例经PCI治疗的STEMI患者术后72 h内超声心动图及心肌超声造影（MCE）检查资料,评估心肌节段MVP水平,对比不同水平MVP心肌节段的纵向应变（LS）和心肌有用功（CMW）、无用功（WW）、MW指数（MWI）及MW率（MWE）;以多因素logistic回归分析观察MVP减低的独立影响因素,以受试者工作特征（ROC）曲线分析其评估MVP减低的效能。结果 共纳入2 142个心肌节段,其中MVP正常组1 515个节段（造影剂恢复充盈时间≤4 s）,延迟组321个节段（造影剂恢复充盈时间>4 s且<10 s）,减低组306个节段（造影剂恢复充盈时间≥10 s）;3组间心肌节段LS、CMW、WW、MWI和MWE总体及两两比较差异均有统计学意义（P均<0.001）。将MVP正常及延迟者归为MVP未减低组,其与减低组间心肌节段LS、CMW、WW、MWI及MWE差异均有统计学意义（P均<0.001）。MWI[OR=1.00,95%CI（1.00,1.00）,P=0.023]、MWE[OR=0.98,95%CI（0.97,1.00）,P=0.010]、CMW[OR=1.00,95%CI（1.00,1.00）,P<0.001]均为MVP减低的独立影响因素,其评估MVP减低的曲线下面积（AUC）分别为0.856、0.853及0.877,CMW大于MWI、MWE （Z=5.246、2.307,P均<0.05）。结论 无创MW可有效评估PCI后STEMI患者心肌节段MVP。     

腺苷负荷动态CT心肌灌注定量评价冠状动脉微循环的实验研究

目的 观察腺苷对心肌灌注的影响，对比腺苷负荷前后心肌灌注变化，并得出定量指标。方法 对10只中华小型猪依次行静息态及负荷态动态CT心肌灌注成像（CT-MPI），测量左心室心肌17个节段、右冠状动脉（RCA）、左前降支（LAD）及回旋支（LCx）3支血管支配心肌，基底部、中间部、心尖部（包括心尖）3个区域及心肌各壁所属节段心肌血流量（MBF）、心肌血容量（MBV）、达峰时间（TTP）及组织通过时间（TTT）。将心肌节段分为静息组和负荷组，比较组间MBF、MBV、TTP及TTT差异。通过腺苷负荷后心肌血流灌注量化指标改变，观察腺苷对冠状动脉微循环的负荷效能。结果 静息组MBF、MBV、TTP及TTT分别为（199.82±66.24）ml/（100 ml·min）、（15.71±5.58）ml/100 ml、（6.38±2.03）s及（13.39±4.91）s；负荷组分别为（278.87±123.24）ml/（100 ml·min）、（20.91±7.66）ml/100 ml、（5.83±1.68）s及（12.53±4.49）s。相比静态组，负荷组MBF、MBV显著升高、TTP缩短（t=8.757、7.738、3.367，P均<0.05），2组TTT差异无统计学意义（t=1.743，P>0.05）。结论 腺苷可增加心肌小型猪血流灌注、缩短灌注TTP；结合动态CT-MPI，可定量分析负荷前后心肌灌注变化及程度。正常心肌组织灌注储备不受腺苷影响。     

三维超声心动图结合心肌超声造影评价2型糖尿病患者心肌功能障碍

目的 探讨实时三维超声心动图结合心肌超声造影对评价2型糖尿病（T2DM）患者心肌功能障碍的价值。方法 选取单纯糖尿病组（Ⅰ组）和糖尿病合并微血管并发症组（Ⅱ组）各29例,对照组（C组）32名,运用实时三维超声心动图获取左心室16节段、12节段及6节段达最小收缩容积时间的标准差（Tmsv16-SD、Tmsv12-SD、Tmsv6-SD）和最大时间差值（Tmsv16-Dif、Tmsv12-Dif和Tmsv6-Dif）及其心率校正值。通过心肌超声造影获得各室壁各节段的峰值强度A、充盈速度β并计算A·β,进行组间数据分析。结果 ①同步性运动评估：Ⅱ组除Tmsv6-Dif以外,其余左心室同步化指标均较C组延长（P均<0.05）;Ⅰ组Tmsv12-Dif、Tmsv12-SD、Tmsv12-Dif%和Tmsv12-SD%较C组延长（P均<0.05）。②心肌血流灌注整体评估：C组、Ⅰ组、Ⅱ组A、β、A·β均呈逐渐下降趋势,Ⅱ组A、β及A·β均低于C组（P均<0.05）;Ⅱ组β及A·β均低于Ⅰ组（P均<0.05）;Ⅰ组β及A·β均低于C组（P均<0.05）;3组内同一指标3个节段差异均无统计学意义（P均>0.05）。结论 单纯T2DM及合并血管并发症患者左心室运动均存在不同步现象;T2DM患者心肌灌注减低,呈弥漫性损害,随其他脏器微循环病变出现而加重。     

心脏MR T2* mapping技术定量评价2型糖尿病患者左心室心肌改变

目的 探讨心脏MR T2^* mapping技术定量评价2型糖尿病（T2DM）患者心肌改变的临床价值。方法 对54例T2DM患者（T2DM组）及43名健康志愿者（正常对照组）采用T2^* mapping技术行心脏MR检查。测量并比较2组间左心室各节段心肌及各支冠状动脉供血区心肌T2^*值的差异。结果 T2DM组左心室第6、15、16节段T2^*值低于正常对照组（P均<0.05）,2组间其余各节段心肌T2^*值差异均无统计学意义（P均>0.05）。T2DM组冠状动脉左回旋支（LCX）供血区心肌T2^*值低于正常对照组（P=0.035）,2组间左前降支（LAD）及右冠状动脉（RCA）供血区心肌T2^*值差异均无统计学意义（P均>0.05）。结论 T2^* mapping技术可用于定量评价T2DM患者左心室心肌改变,有助于早期发现糖尿病心肌病。     

核素心肌灌注的定量及异质性分析对病毒性心肌炎的诊断价值

目的 探讨核素心肌灌注的定量及异质性分析诊断病毒性心肌炎（VMC）的价值。方法 回顾性分析接受^99mTc-MIBI心肌灌注显像的疑似VMC患者37例,其中18例临床诊断为VMC（VMC组）,其余19例排除VMC的患者为非VMC组。使用QPS软件获得静息灌注总积分（SRS）及总灌注缺损值（TPD）,计算靶心图放射性计数异质性参数节段靶心图变异系数（CV_s）和室壁靶心图变异系数（CV_w）,比较2组心肌灌注各参数的差异。应用ROC曲线评价各参数对VMC的诊断效能。结果 VMC组心肌灌注以左心室前壁和下壁降低最显著（P均<0.05）;VMC组TPD、CV_s较非VMC组均明显增高（P均<0.05）;CV_s对VMC炎诊断效能最优（AUC=0.83,P<0.01）,当CV_s阈值为10.5%时,其灵敏度为94.4%,特异度为73.7%。结论 心肌灌注异质性分析有助于VMC的诊断和鉴别诊断。     

MR心肌首过灌注成像评估肥厚型心肌病心肌缺血

目的 采用MR心肌首过灌注成像评估肥厚型心肌病（HCM）心肌缺血情况。方法 选取20例HCM患者（HCM组）和10名健康志愿者（对照组）行CMR检查（包括左心室短轴电影、心肌首过灌注成像和延迟增强扫描）,测量舒张末期心肌厚度（EDTH）,绘制左心室基底部、中部及心尖部的血池-信号强度心肌灌注曲线,获得各节段达峰时间（t_peak）、心肌信号强度最大上升斜率（Slope_max）、峰值信号强度（SI_peak）等。根据EDTH,将HCM组各心肌节段分为非肥厚亚组和肥厚亚组,肥厚亚组又分为轻度肥厚（15~19 mm）、中度肥厚（20~24 mm）和重度肥厚（25~29 mm）节段3个水平,采用单因素方差分析比较所有组别t_peak、Slope_max、SI_peak的总体差异,对HCM各亚组及各水平的t_peak、Slope_max、SI_peak行两两检验。结果 对照组与HCM非肥厚亚组的Slope_max、t_peak差异均无统计学意义（P均>0.05）。HCM非肥厚亚组与HCM肥厚亚组Slope_max、t_peak差异均有统计学意义（P均<0.05）。HCM肥厚亚组中,轻度肥厚水平Slope_max明显高于中度和重度肥厚（P均<0.05）,中度肥厚水平t_peak高于轻度肥厚（P<0.05）;中度与重度肥厚间Slope_max、t_peak及轻度、中度和重度肥厚间SI_peak差异均无统计学意义（P均>0.05）。结论 MR心肌首过灌注成像可反映HCM不同肥厚节段的心肌缺血情况,有助于对HCM患者进行风险分层、制定治疗计划和预后评估。     

超声斑点追踪成像技术评价多发性骨髓瘤患者的心肌功能

目的 采用超声斑点追踪成像技术观察左心室射血分数（LVEF）正常的多发性骨髓瘤（MM）患者心肌收缩功能变化。方法 将40例多发性骨髓瘤患者（LVEF≥50%）分为室壁厚度正常组（n=13）及室壁厚度增厚组（n=27）,以健康体检者40名为正常对照组,对所有受检者行常规超声参数测定及二维斑点追踪成像分析。结果 室壁厚度增厚组及室壁厚度正常组心尖部及左心室短轴位心肌各节段较正常对照组的二维纵向收缩期、二维径向收缩期峰值应变明显减低（P均<0.05）,室壁增厚组减低更为明显。室壁厚度正常组、室壁厚度增厚组二尖瓣水平前壁、前间隔及室壁厚度增厚组乳头肌水平左心室后壁二维圆周收缩期峰值应变较正常对照组明显减低（P均<0.05）,其余节段心肌二维圆周收缩期峰值应变差异无统计学意义（P均>0.05）。结论 MM患者在常规超声检查出现特征性改变之前,心肌纵向及径向收缩功能均已出现减低,但圆周运动未出现显著改变。     

心肌分层应变技术评价低温条件下兔左心室心肌纵向收缩功能

目的 应用分层应变技术评价不同低温条件下兔左心室心肌纵向收缩功能变化。方法 选取新西兰兔30只，随机分为常温组、低温A组、低温B组，每组10只，常温组置于室温22~25℃，低温A、B组分别置于-25℃条件下4 h和8 h。比较各组心内膜层、中层及心外膜层的心肌收缩期纵向峰值应变（LS）。结果 3组心肌LS值由心内膜层至心外膜层呈递减趋势；低温A组心内膜层心肌LS绝对值较常温组降低（P<0.05），低温B组3层心肌LS值绝对值较常温组均明显降低（P均<0.01）；低温B组3层心肌LS值的绝对值均显著低于低温A组（P均<0.05）。结论 新西兰兔左心室壁3层心肌LS值随低温时间改变受累程度不同，心肌纵向分层应变技术可更早发现左心室收缩功能减低，心内膜层心肌应变较心外膜层心肌应变敏感。     

心血管MR组织追踪技术定量评估肥厚型心肌病右心室心肌应变

目的 探讨心脏MR组织追踪（CMR-TT）技术评价肥厚型心肌病（HCM）右心室功能的可行性及右心室应变与左心室应变的相关性。方法 对32例HCM患者（HCM组）及32名健康志愿者（对照组）行CMR电影序列扫描,测量心功能及左、右心室应变参数。结果 HCM组左心室质量较对照组明显增高（t=11.26,P<0.001）,其余左心功能参数（左心室射血分数、舒张末期容积、收缩末期容积）2组间差异均无统计学意义（P均>0.05）。与对照组比较,HCM组左心室、右心室整体圆周应变（GCS）、整体径向应变（GRS）和整体纵向应变（GLS）均明显减低（P均<0.05）;除左、右心室基底部径向应变外,HCM组各节段局部应变较对照组减低（P均<0.05）。HCM组右心室GRS与左心室GRS呈正相关（r=0.375,P=0.034）,与左心室GLS呈负相关（r=-0.466,P=0.007）;右心室GCS与左心室GCS、GLS均呈正相关（r=0.531、0.462,P=0.002、0.008）。结论 右心室节段应变、整体应变能敏感地反映HCM右心室心肌收缩功能;HCM患者在左心室射血分数减低前左、右心室心肌收缩功能已存在受损;HCM右心室与左心室心肌收缩功能受损存在一定相关性。     

Guns and Knives in New Mexico: Patterns of Penetrating Trauma, 1978–1993

Objective: To identify patterns of nonfatal and fatal penetrating trauma among children and adults in New Mexico using ED and medical examiner data.
Methods: The authors retrospectively sampled in 5-year intervals all victims of penetrating trauma who presented to either the state Level-1 trauma center or the state medical examiner from a 16-year period (1978–1993). Rates of nonfatal and fatal firearm and stabbing injury were compared for children and adults.
Results: Rates of nonfatal injury were similar (firearm, 34.3 per 100,000 person-years; stabbing, 35.1). However, rates of fatal injury were significantly different (firearm, 21.9; stabbing, 2.7; relative risk: 8.2; 95% confidence interval: 5.4, 12.5). From 1978 to 1993, nonfatal injury rates increased for children (p = 0.0043) and adults (p < 0.0001), while fatal penetrating injury remained constant. The increase in nonfatal injury in children resulted from increased firearm injury rates. In adults, both stabbing and firearm nonfatal injury rates increased.
Conclusions: Nonfatal injury data suggest that nonfatal violence has increased; fatal injury data suggest that violent death rates have remained constant. Injury patterns vary by age, mechanism of trauma, and data source. These results suggest that ED and medical examiner data differ and that both are needed to guide injury prevention programs.     

Interprofessional approaches to creating safe,high quality health care

Three supplementary perspectives are presented arguing that interprofessional collaboration is both necessary and desirable. Nonetheless, there are often too many serious intra-professional barriers and obstacles to interprofessional collaboration to make it successful. Some of these barriers, it is argued and illustrated, are found in the multiple ways in which professional identity is tacitly acquired and embodied in the practitioners' habitual, everyday practice. The paper then explores ways in which reflection, especially Second order reflection, can help to elucidate and overcome these obstacles, as well as increasing professional adaptability and competence.     

Systematic Reviews Published in the January 2011 Issue of The Cochrane Library

ABSTRACT

The Cochrane Library of Systematic Reviews is published quarterly as a DVD and monthly online. The January 2011 issue (first quarterly DVD for 2011) contains 4515 complete reviews, 1985 protocols for reviews in production, and 13,521 one-page summaries of systematic reviews published in the general medical literature. In addition, there are citations of 641,000 randomized controlled trials, and 14,018 cited papers in the Cochrane methodology register. The health technology assessment database contains over 9300 citations. One hundred and seven new reviews have been published in the last 3 months, of which five have potential relevance for practitioners in pain and palliative medicine.     

Prospects for the control of neglected tropical diseases by mass drug administration

The prospects for the control of neglected tropical diseases, including soil-transmitted helminthiasis, shistosomiasis, lymphatic filariasis, onchocerciasis and trachoma, through mass drug administration, are exemplified by the elimination of the trachoma as a public-health problem in Morocco. In spite of this and other striking successes, mass drug administration programs are faced with major challenges resulting from suboptimal coverage and lack of efficacy. At current suboptimal coverage rates, programs may need prolongation for an extended period, increasing costs and undermining sustainability. Community participation through health education and information appears to be crucial to improve coverage and to achieve sustainability. Implementation of complementary measures, such as vector control, improved hygiene and environmental sanitation, are important to further control transmission and to prevent re-emergence of the infection and, again, may only be achieved effectively through community-based initiatives. To reduce costs and to relieve pressure on the health system, combining neglected tropical disease programs in areas where diseases coexist and integration with existing control programs for malaria, tuberculosis and HIV/AIDS is advocated. The risk of developing drug resistance is of particular concern in view of the lack of alternative drugs, and reduced treatment efficacy due to emerging resistance is evident for the soil-transmitted helminths and onchocerciasis. Given the risk for the development of drug resistance and the need for a high degree of participation, close attention should be paid to the monitoring of the coverage and efficacy of the different program components.     

Bacterial meningitis: an update of new treatment options

The outcome of bacterial meningitis critically depends on the rapid initiation of bactericidal antibiotic therapy and adequate management of septic shock. In community-acquired meningitis, the choice of an optimum initial empirical antibiotic regimen depends on the regional resistance patterns. Pathogens resistant to antibacterials prevail in nosocomial bacterial meningitis. Dexamethasone is recommended as adjunctive therapy for community-acquired meningitis in developed countries. In comatose patients, aggressive measures to lower intracranial pressure <20 mmHg (in particular, external ventriculostomy, osmotherapy and temporary hyperventilation) were effective in a case–control study. Although many experimental approaches were protective in animal models, none of them has been proven effective in patients. Antibiotics, which are bactericidal but do not lyse bacteria, and inhibitors of matrix metalloproteinases or complement factor C5 appear the most promising therapeutic options. At present, vaccination is the most efficient method to reduce disease burden. Palmitoylethanolamide appears promising to enhance the resistance of the brain to infections.     

Prise en charge des entorses externes de cheville : étude clinique préliminaire sur l’efficacité du dispositif Myolux™

Ankle sprains are the most common injury of the musculoskeletal system and are associated with significant societal and economic impacts. It has been proven that classical therapeutic strategies may not be effective in preventing recurrent injuries: the recurrence rates reported in the literature can reach 73%. In order to provide an effective rehabilitation solution, a destabilizing orthosis was developed. This device is equipped with a mechanical articulator reproducing the subtalar mechanics and placed under the heel. In this paper, we present the main results of a preliminary clinical study conducted between 2004 and 2007. All subjects included in this study were treated with the abovementioned orthosis during 10 rehabilitation sessions of 30 minutes each. Data show a relatively low recurrence rate of 12% for the overall population. Moreover, it's of primary importance to note that this satisfactory ratio is largely reduced (3% of recurrence rate) for the 29 patients who performed one training session per month after the 10th initial rehabilitation sessions. Hence, the destabilizing orthosis appears to be an effective solution to prevent recurrent ankle sprains. However, joint protection requires long-term and regular training sessions. This result has motivated the development of a similar device allowing patients to perform training sessions at home. Finally, data obtained in this study are promising awaiting the final results of the comparative, multicentric and independent clinical trials currently managed by the Hospices Civils de Lyon.     

Imaging choices in occult hip fracture

Background: Hip fracture is a common injury, with an incidence rate of > 250,000 per year in the United States. Diagnosis is particularly important due to the high dependence on the integrity of the hip in the daily life of most people. Objectives: In this article we review the literature focused on hip fracture detection and discuss advantages and limitations of each major imaging modality. Discussion: Plain radiographs are usually sufficient for diagnosis as they are at least 90% sensitive for hip fracture. However, in the 3–4% of Emergency Department (ED) patients having hip X-ray studies who harbor an occult hip fracture, the Emergency Physician must choose among several methods, each with intrinsic limitations, for further evaluation. These methods include computed tomography, scintigraphy, and magnetic resonance imaging. Conclusion: We present an evidence-based algorithm for the evaluation of a patient suspected to have an occult hip fracture in the ED. Also outlined are future directions for research to distinguish more effective techniques for identifying occult hip fractures.     

Systematic Reviews Published in the April 2012 Issue of the Cochrane Library

ABSTRACT

The Cochrane Library of Systematic Reviews is published quarterly as a DVD but monthly online. The April 2012 issue (second DVD for 2012) contains 5045 complete reviews, 2182 protocols for reviews in production, and 17,084 short summaries of systematic reviews published in the general medical literature. In addition, there are citations of 674,000 randomized controlled trials, and 15,400 cited papers in the Cochrane methodology register. The health technology assessment database contains just over 11,000 citations. One hundred and seventeen new reviews have been published in the last 3 months of which 12 have potential relevance for practitioners in pain and palliative medicine. The impact factor of the Cochrane Library stands at 6.186. Readers are encouraged to access the full report for any articles of interest as only a brief commentary is provided.     

Platelets,thrombosis, coagulation,and atherosclerosis

When I first got the invitation to join a medical delegation going to Moldova, I thought for a moment that our destination was the fictional country in the old Marx Brothers movie Duck Soup. On further checking, it turns out that entertaining place was called Freedonia. I now know that Moldova is indeed a real country, bordered on the west by Romania and on the other three sides by the Ukraine. It is a proud country, rich with traditions, and its people are warm, giving, eager to learn ways to improve their healthcare system, and deeply appreciative of our attempts to help them in the task.