红细胞分布宽度对急性呼吸窘迫综合征患者预后的判断价值及与APACHE Ⅱ评分的相关性分析

目的:本文旨在研究红细胞分布宽度(RDW)对判断急性呼吸窘迫综合征(ARDS)患者预后的价值,分析其与急性生理学与慢性健康状况评分系统Ⅱ(APACHE Ⅱ评分)的相关性。方法:对86例ARDS患者进行回顾性分析,根据患者预后情况分为生存组和死亡组,搜集入院24 h内血常规中RDW值,并计算APACHE Ⅱ评分,比较2组之间的差别,评价RDW对ARDS患者预后的判断价值,剖析其与APACHE Ⅱ评分的相关性。结果:2组年龄、性别、住院天数差异无统计学意义(P0.05),死亡组患者入院24 h内RDW、APACHEⅡ评分均显著高于存活组,差异均有统计学意义(P0.05)。Spearman相关性分析显示,患者入院24 h内时RDW与APACHEⅡ评分呈显著正相关关系(r=0.439,P0.05)。RDW的AUC曲线下面积为0.896(95%CI 0.827～0.964),灵敏度为0.860,特异度为0.862,截断值为14.15%;APACHEⅡ评分AUC曲线下面积为0.920(95%CI 0.861～0.979),灵敏度为0.877,特异度为0.828,截断值为15.5分。多元Logistic回归分析显示:RDW和APACHEⅡ评分能够作为ARDS患者预后的独立预测因子。结论:入院24 h内RDW及APACHEⅡ评分对判断ARDS患者预后具有重要价值,是评估预后的独立因子,且RDW与APACHEⅡ评分具有显著正相关性。     

降钙素原联合脓毒症死亡风险评分对老年脓毒症患者预后的评估价值

目的:探讨降钙素原(PCT)联合脓毒症死亡风险评分(MEDS)对老年脓毒症患者预后的评估价值。方法:选择我院急诊监护室81例老年脓毒症患者,入院后给予血常规,PCT,血气分析及生物化学全项等检查,并进行急性生理及慢性健康状况评分(APACHEⅡ)和MEDS评分。随访28d,根据预后患者分成死亡组(19例)和存活组(62例),分别比较两组患者PCT、白细胞(WBC)、MEDS评分和APACHEⅡ评分的区别,同时比较A PACHEⅡ评分、PCT、MEDS评分、PCT和MEDS评分2者联合预测死亡的ROC曲线下面积的区别。结果:死亡组患者PCT、MEDS评分和APACHEⅡ评分均大于存活组(P0.05),WBC比较差异无统计学意义(P=0.810);PCT预测死亡的ROC曲线下面积为0.719(P0.01),MEDS预测死亡的ROC曲线下面积为0.667(P0.05),APACHE II评分ROC曲线下面积为0.852(P0.01),均大于PCT和MEDS评分(P0.05),PCT和MEDS评分2者联合预测死亡的ROC曲线下面积0.756(P0.01),与APACHE II评分比较差异无统计学意义(P=0.086)。结论:PCT联合MEDS评分可以准确评估老年脓毒症患者的病情,与APACHE II评分比较具有相近的评估病情作用。     

急诊脓毒症改良死亡风险评分对急诊脓毒症患者危险分层的应用

目的 探讨急诊脓毒症改良死亡风险评分(NMEDS)对急诊脓毒症患者危险分层的应用价值.方法 连续入选海南省农垦总医院急诊科2015年1月1日至2015年8月31日急诊就诊并且明确诊断为脓毒症患者164例,随访28 d按照患者预后分为死亡组(48例)和存活组(116例)两组,比较两组患者入院后24h内NMEDS与急性生理学与慢性健康状况评分系统Ⅱ(APACHEⅡ)评分;并描绘受试者工作特征曲线(ROC曲线),分析NMEDS与APACHEⅡ评分对急诊脓毒症患者死亡危险预后能力的比较.结果 死亡组患者在入院24h内NMEDS分值明显高于存活组(13.4±1.8)vs.(5.8±2.1),P ＜0.01;APACHEⅡ评分相比较,死亡组(27.4±3.6)分较存活组(17.6±4.1)分高,P=0.003;NMEDS评分不同分值28 d患者病死率:≤4分为4.5％,5～8分为10.0％,9～12分为19.4％,13～16分为42.4％,≥17分为66.7％.NMEDS对患者28 d死亡风险预测的ROC曲线下面积为0.788,数值上较APACHEⅡ评分曲线下面积为0.701高,但差异无统计学意义,P=0.056.结论 NMEDS对急诊脓毒症患者是可以应用的危险分层评分系统,在急诊临床工作中具有应用价值.     

血清肝素结合蛋白水平联合入院24 h乳酸清除率对肺炎并发脓毒症患者预后的评估价值研究

目的:评估血清肝素结合蛋白(HBP)水平联合24 h乳酸清除率(24 h LCR)对肺炎并发脓毒症患者预后判断的价值。方法:选取74例肺炎并发脓毒症患者,根据患者28 d预后分为存活组(51例)、死亡组(23例)。采用酶联免疫吸附(ELISA)法检测患者血清HBP水平;采用血气分析仪检测患者体内血乳酸含量,并计算24 h LCR;采用Pearson法分析HBP水平、24 h LCR与急性生理与慢性健康评分(APACHEⅡ)的相关性;采用受试者工作特征(ROC)曲线评估HBP、24 h LCR对肺炎并发脓毒症患者的预后价值;采用COX回归分析影响肺炎并发脓毒症患者预后的因素。结果:①多因素分析显示,HBP高水平、24 h LCR低水平及APACHEⅡ评分是影响肺炎并发脓毒症患者不良预后的独立危险因素。②死亡组肺炎并发脓毒症患者HBP水平、APACHEⅡ评分明显高于存活组,24 h LCR水平明显低于存活组,差异有统计学意义(P0.05);③肺炎并发脓毒症患者血清HBP水平与APACHEⅡ评分呈正相关,24 h LCR与APACHEⅡ评分呈负相关,差异有统计学意义(P0.05)。④HBP预测肺炎并发脓毒症不良预后的曲线下面积(AUC)为0.874,截断值为22.89 ng/mL,其灵敏度、特异度分别为73.9%、92.2%;24 h LCR预测肺炎并发脓毒症不良预后的AUC为0.883,截断值为30.77%,其灵敏度、特异度分别为87.0%、80.4%;HBP联合24 h LCR预测肺炎并发脓毒症不良预后的AUC为0.932,其灵敏度、特异度分别为82.6%、98.0%;结论:死亡组肺炎并发脓毒症患者血清中HBP呈高水平,24 h LCR呈低水平,二者联合检测对肺炎并发脓毒症患者预后评估有一定参考价值。     

英国国家早期预警评分对急诊老年严重脓毒症及脓毒症休克患者预后的评估价值

目的探讨英国国家早期预警评分(NEWS)对急诊老年严重脓毒症及脓毒性休克患者病情及预后的评估。方法收集首都医科大学宣武医院急诊老年严重脓毒症和脓毒性休克患者116例,就诊后采集患者的常规生理生化指标,并行NEWS评分,APACHEⅡ评分和SOFA评分,随访28 d,根据患者预后分为死亡组和存活组,分别比较死亡组和存活组NEWS评分,APACHEⅡ评分及SOFA评分区别;比较脓毒性休克和严重脓毒症组的NEWS评分,APACHEⅡ评分及SOFA评分的区别;NEWS评分与APACHEⅡ评分。SOFA评分的相关性分析;通过分析ROC曲线下面积(AUC)确定NEWS评分对老年严重脓毒症和脓毒性休克患者预后的评估价值。结果脓毒性休克组患者NEWS评分;APACHEII评分和SOFA评分大于严重脓毒症组;死亡组NEWS评分;APACHEII评分和SOFA评分均显著大于存活组(P<0.05);NEWS评分水平与APACHEⅡ评分。SOFA评分具有显著相关性(r=0.807、0.883,P<0.05),NEWS评分;APACHEII评分和SOFA评分预测死亡ROC曲线下面积分别为0.870、880、0.865(P>0.05)。结论 NEWS评分对急诊老年严重脓毒症和脓毒性休克患者的病情和预后具有重要的评估价值,评分愈高提示患者预后愈差。     

乳酸清除率、乳酸和APACHE Ⅱ评分对急性百草枯中毒患者预后的相关研究

目的：研究百草枯中毒患者乳酸、12h乳酸清除率和APACHEⅡ评分与患者预后的相关性。方法：回顾性研究2009-01-2013-12百草枯中毒患者95例,按生存组和死亡组比较入院时乳酸值、12h乳酸清除率和APACHEⅡ评分与患者预后的分析。结果：急性百草枯中毒死亡组患者入院时乳酸、APACHEⅡ评分、24h APACHEⅡ评分均高于生存组（P〈0.05）,乳酸清除率低于生存组（P〈0.05）。乳酸、入院APACHEⅡ评分、24hAPACHEⅡ评分与死亡呈正相关。12h乳酸清除率与死亡呈显著负相关。入院时APACHEⅡ评分和乳酸清除率的ROC曲线下面积大于入院时乳酸和入院后24hAPACHEⅡ评分的ROC曲线下面积,研究对象与预测中毒预后的良好指标百草枯血浆浓度面积接近。根据最佳截断值,乳酸、乳酸清除率、百草枯血浆浓度、入院APACHEⅡ评分、24hAPACHEⅡ评分预测病死率的灵敏度、特异度、Youden指数分别为0.727~0.909,0.667~0.921,0.485~0.642。结论：入院时APACHEⅡ评分和早期乳酸清除率对急性百草枯中毒病死有更好的预测能力。     

降钙素原和乳酸动态变化对急诊老年严重脓毒症和脓毒性休克患者预后的评估价值

目的研究血浆降钙素原(Procalcitonin,PCT)和动脉血乳酸动态变化情况对老年严重脓毒症及脓毒性休克患者病情和预后的评估作用。方法收集首都医科大学宣武医院急诊监护室老年严重脓毒症和脓毒性休克患者163例,入院后给予PCT和动脉血乳酸等检查,并给与APACHEⅡ评分(Acute Physiology and Chronic Health EvaluationⅡ)。入院后6h复查血乳酸,5d复查PCT,随访28d根据预后患者分为死亡组和存活组,分别比较死亡组和存活组PCT和乳酸区别和2组乳酸和PCT的变化情况;比较脓毒性休克和严重脓毒症组的PCT,乳酸和APACHEⅡ评分的区别;用ROC曲线下面积(AUC)分析PCT和动脉血乳酸预测老年严重脓毒症和脓毒性休克患者死亡的价值。结果脓毒性休克组患者PCT、乳酸和APACHE II评分大于严重脓毒症组;死亡组PCT和乳酸均大于存活组(P0.05),6h乳酸和5d的PCT的差别更明显,死亡组乳酸和PCT前后比较无显著性差异(P0.05),存活组乳酸和PCT较前明显下降(P0.01);PCT预测死亡ROC曲线下面积为0.803,动脉血乳酸曲线下面积为0.796,两者比较无统计学差异(P0.05)。结论 PCT和动脉血乳酸对急诊老年严重脓毒症和脓毒性休克患者的病情和预后具有重要的评估价值,PCT和乳酸含量持续保持高水平的提示预后差。     

脓毒症患者血清miR-205和HMGB1的表达关系及意义

目的:检测脓毒症患者血清miR-205、高迁移率族蛋白B1(HMGB1)的表达水平,并探讨二者在脓毒症中的关系及意义。方法:随机选取2017-03-12—2019-09-20期间于本院就诊的55例脓毒症患者为观察组,根据患者21 d时的生存情况分为存活组和死亡组,同期选取于本院进行体检的50例健康人群为对照组,采用qRT-PCR法检测各组血清miR-205水平,采用酶联免疫吸附(ELISA)法检测血清中HMGB1的表达水平,采用Pearson法分析血清miR-205、HMGB1水平与反映疾病严重程度的急性生理学和慢性健康评分Ⅱ(APACHEⅡ)评分、多器官功能障碍综合征(MODS)评分的相关性,采用ROC曲线分析血清miR-205、HMGB1及APACHEⅡ评分对脓毒症患者不良预后的预测价值。结果:观察组血清miR-205表达水平显著低于对照组,血清HMGB1水平显著高于对照组(P0.05);死亡组APACHEⅡ评分、MODS评分及血清HMGB1水平均显著高于存活组,血清miR-205水平显著低于存活组(P0.05);Pearson法分析结果显示,脓毒症患者血清miR-205与HMGB1、APACHEⅡ评分均呈负相关(P0.05),HMGB1与APACHEⅡ评分呈正相关(P0.05),血清miR-205、HMGB1与MODS评分均无相关性(P0.05);ROC曲线分析结果显示,血清miR-205预测脓毒症患者不良预后的曲线下面积为0.851,敏感度为67.30%,特异度为92.00%;血清HMGB1预测不良预后的曲线下面积为0.888,敏感度为76.40%,特异度为94.00%;APACHEⅡ评分预测不良预后的曲线下面积为0.908,敏感度为83.30%,特异度为88.90%。结论:脓毒症患者血清miR-205水平降低,血清HMGB1水平升高,对患者不良预后有一定预测价值。     

红细胞分布宽度对感染患者预后的评估价值北大核心CSCD

目的探讨细菌感染患者的红细胞分布宽度(RDW)与疾病危重程度及预后的关系。方法采用回顾性研究,选择安徽医科大学附属省立医院2013-2015年综合ICU血培养阳性患者112例,统计分析患者的急性生理与慢性健康评估Ⅱ(APACHE-II)评分、RDW、红细胞平均体积、血红蛋白、C反应蛋白(CRP)、降钙素原(PCT)和血清肌酐。根据患者的预后情况分为存活组和死亡组,对两组的相关指标进行比较。采用Spearman's相关性分析RDW与相应检测指标的相关性,采用多因素Logistic回归分析影响预后的独立危险因素,绘制受试者工作特征(ROC)曲线计算曲线下面积,比较危险因素对感染患者的死亡预测价值。采用Kaplan-Meier生存分析,按RDW分层,绘制30 d生存曲线,比较RDW值与死亡预后的关系。结果 RDW与CRP、PCT、APACHEⅡ评分呈正相关(r值分别为0.225、0.266、0.267,P<0.05);Logistic回归分析显示,RDW和APACHEⅡ评分是影响感染患者预后的独立危险因素;RDW的ROC曲线的曲线下面积为0.634,灵敏度为0.600,特异度为0.641。结论 RDW可以作为预测细菌感染患者预后的参考指标,对感染患者的预后具有较好的灵敏度。     

脓毒症患者降钙素原及动脉乳酸与碱剩余变化的临床意义

目的了解脓毒症患者降钙素原(PCT)、动脉乳酸、碱剩余(BE)变化特点及其对脓毒症患者严重程度及预后的影响。方法收集70例脓毒症患者临床资料,测定入院和入院24小时、48小时动脉乳酸、BE等指标,并计算24小时、48小时乳酸清除率;根据患者入院24小时内最差临床指标计算急性生理与慢性健康(APACHEⅡ)评分;根据疾病严重程度分为轻度脓毒症组(n=40)与严重脓毒症组(n=30),根据28天转归分为死亡组(n=14)与存活组(n=56);采用logistic回归分析影响脓毒症患者预后的危险因素,绘制ROC曲线并计算曲线下面积,比较其对判断脓毒症患者预后的价值;采用Pearson相关分析PCT与动脉乳酸、BE及APACHEⅡ评分相关性。结果随脓毒症患者严重程度增加,PCT、APACHEⅡ评分、入院动脉乳酸水平升高,BE水平降低(P<0.05),PCT 0.49(1.63)μg/Lvs 2.90(5.45)μg/L、APACHEⅡ评分13.00(6.00)vs 20.50(8.25)、入院乳酸2.55(1.38)mmol/L vs 5.55(1.48)mmol/L、BE-6.80(4.43)mmol/L vs-8.55(6.20)mmol/L(均P<0.05);死亡组入院24小时、入院48小时乳酸清除率明显低于存活组,24小时乳酸清除率13.39(16.97)%vs 34.78(30.00)%、48小时乳酸清除率7.71(39.38)%vs 62.96(24.73)%,BE明显低于存活组(均P<0.05);死亡组PCT、APACHEⅡ评分与入院乳酸明显高于存活组(P<0.05),PCT 9.00(11.40)μg/L vs 0.49(1.62)μg/L、APACHEⅡ评分21.50(3.25)vs 14.00(7.75)、入院乳酸6.75(4.55)mmol/L vs 2.27(1.30)mmol/L,BE-9.25(4.55)mmol/L vs-6.80(4.45)mmol/L(均P<0.05);脓毒症患者PCT与入院乳酸及APACHEⅡ评分呈正相关,与入院BE水平呈负相关;经logistic回归分析,24小时乳酸清除率、PCT、APACHEⅡ评分为影响脓毒症患者预后的独立危险因素;24小时乳酸清除率结合PCT的ROC曲线下面积为0.960,敏感度、特异度较大。结论早期动脉乳酸,PCT与BE可作为判断脓毒症患者病情严重程度的指标。24小时乳酸清除率、PCT、APACHEⅡ评分对判断脓毒症患者预后有重要意义。     

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.     

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.     

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.