经桡动脉与经股动脉入径行急诊经皮冠状动脉介入治疗ST段抬高型急性心肌梗死临床对比研究

目的比较经桡动脉与经股动脉入径行急诊经皮冠状动脉介入(PCI)治疗ST段抬高型急性心肌梗死(STEMI)的有效性及安全性。方法选择接受急诊PCI的STEMI患者112例,其中桡动脉组77例,股动脉组35例,比较两组手术成功率、介入治疗术中、术后相关指标、并发症发生率及6个月的随访结果。结果两组手术成功率均100%,处理梗死相关血管所需的指引导管数[(1.12±0.23)根vs.(1.08±0.34)根]、穿刺至球囊扩张时间[(42.34±1.23)min vs.(48.18±2.34)min]、术中球囊数[(1.21±0.32)个vs.(1.18±0.25)个]、术中支架的使用数[(1.15±0.37)个vs.(1.16±0.21)个]、造影剂用量[(98.32±8.51)ml vs.(95.45±7.23)ml]差异无统计学意义,血管穿刺相关并发症中桡动脉组发生皮下血肿伴局部皮肤水疱8例,比股动脉组发生穿刺部位血肿13例少(P<0.05);桡动脉组无血管迷走反射发生,股动脉组在术后拔管压迫止血中发生血管迷走神经反射5例;桡动脉组有1例导尿,股动脉组6例术后行导尿;住院天数桡动脉组明显较股动脉组少[(7.45±0.61)d vs.(8.39±0.53)d,P<0.05];住院期间桡动脉组因泵衰竭死亡1例,恶性心律失常猝死1例,股动脉组因泵衰竭死亡1例;术后6个月门诊或电话随访期间两组均无MACE以及靶血管再次血运重建发生。结论经桡动脉与经股动脉入径行急诊PCI治疗STEMI均有效、安全,但前者可以明显减少血管并发症、血管迷走神经反射和导尿的发生率,缩短平均住院日。     

环境适应表达训练对全喉切除术患者生活质量及心理变化的影响

目的:全喉切除术患者术后的生活质量及心理都发生了很大变化,探讨环境适应表达训练对其这方面的改善作用。方法:选择 1999-06/2001-06在商丘市第一人民医院耳鼻咽喉科病理诊断为喉癌并行全喉切除术术后患者 104例,依患者是否接受环境适应表达训练分为观察组 54例,对照组 50例。观察组在此基础上进行环境适应表达训练,每天一两小时,回院后与患者及家人分析在外界环境中交流遇到的问题,指导患者找出解决的方法,所有患者出院前根据最易出现的几种情绪制定问卷表,同时采用医院焦虑抑郁情绪测定(hospital anxiety and depression scale,HAD 量表进行问卷调查及出院 6 )个月后通过门诊及信函进行上述问卷调查并进行统计分析。结果:获随访的观察组 39例,对照组 33例,两组患者的各项生活质量分及负性心理情绪发生率术后 4周比较差异无显著性意义 P >0.05) ( 。出院后 6个月时 H AD 中活动、娱乐、工作、交流各项评分比较差异有显著性或非常显著性意义,对照组分别为(70.14±17.5),(64.01±19.04),(36.17±24.71),(40.06±24.89)分,观察组为 (88.70±22.33),(77.42±23.15),(54.02±29.34),(73.30±20.56)分 (P <0.05或 P<0.01)。负性心理情绪发生     

腰椎间盘突出症术后高压氧治疗的临床实验

目的:探讨高压氧治疗能否减轻腰椎间盘术后的水肿,促进受损神经根尽快恢复及临床症状的缓解。方法:采取随机抽签法将46例患者分为两组,一组术后采用高压氧治疗,另一组做对照组。结果:治疗组术后3,7,14dVAS评分分别为(6.0±1.2),(2.6±1.2),(1.2±1.0)分,对照组分别为(7.7±0.8),(5.6±1.0),(4.8±1.4)分,与对照组比较差异有显著性意义(P=0.000,F=133.433,df1=1,df2=44)。治疗组术后疼痛时间(1.6±1.1)d,对照组术后疼痛时间(4.5±1.8)d。术后疼痛时间两组比较差异有显著性意义(t=6.709,P<0.001)。体感诱发电位(SEP)变化:治疗组P40差值2.3±2.4,对照组2.0±2.1,与对照组比较差异无显著性意义(t=0.453,P>0.05)。结论:术后高压氧治疗有助于神经根的复原,SEP在治疗前后不显著,可能与SEP不敏感有关,须进一步观察。     

自体骨髓单个核细胞移植治疗扩张型心肌病的临床观察

目的:观察自体骨髓单个核细胞冠脉内移植治疗扩张型心肌病的临床疗效。方法:扩张型心肌病16例(男性5例, 女性11例),平均年龄(45．3±10．8)岁,心功能Ⅳ级,左室射血分数(LVEF)<30％。抽取骨髓,用Ficoll密度梯度离心法分离骨髓单个核细胞,经外周动脉穿刺插管,将骨髓单个核细胞分别直接注入左、右冠脉。比较移植前后心功能的变化。结果:移植3个月后,心功能(NYHA分级)得到改善,总有效率87．5％,超声心动图检查均示左室舒张末径(mm)(72．94± 4．01 vs 63．63±2．58．P<0．001)、左室收缩末径(mm)(52．00±2．80 vs 44．38±1．78．P<0．001)减小,左室射血分数(％) (22．88±5．29vs33．81±3．33,P<0．001)、短轴缩短率(％)(12．00±2．39 vs 20．94±3．70,P<0．001)明显增加;心脏ECT 检查与术前相比,术后患者缺血及坏死心肌节段减少,(3．4±0．3vs2．1±0．4,P<0．05)(2．5±0．5 vs 1．6±0.3,P< 0．01)个。结论:自体骨髓单个核细胞移植有可能通过缺血心肌血运改善,坏死心肌区有心肌细胞再生而改善扩张型心肌病的心功能。     

定量组织速度成像对梗死心肌局部收缩运动的评估价值

目的:探讨定量组织速度成像技术在评价梗死心肌局部收缩运动和精确性能。方法:①选择2004-03/05在解放军总医院老年心血管病研究所住院心肌梗死患者32例,男20例,女12例,年龄(58±13)岁。均能够耐受超声检查和能保证在6个月内随访,获完全知情同意并均自愿参加。受累部位分别为左室下壁14例,前壁10例,前间壁7例,高侧壁1例。②选择同期本院健康体检自愿者20名,男女各10名,平均年龄(56±10)岁;均无心血管系统疾病,将该测得结果作为正常参考值。③采用彩色超声诊断仪于心肌梗死患者经皮冠状动脉血管成形术术前1d及术后1周,1,2,6个月5个时间点行超声检查,即进行6个月的随访。观察心肌梗死患者左室梗死区域心肌收缩运动变化,记录各受累节段中点内膜下心肌组织峰值收缩速度和收缩期加速度。④组间计量资料差异性测定采用t检验。结果:随访期间有1例广泛前壁梗死患者于经皮冠状动脉血管成形术术后出现再狭窄未进入结果分析,进入结果分析心肌梗死患者31例。经皮冠状动脉血管成形术前后心肌梗死患者左室下壁、前壁、前间壁、高侧壁受累心肌运动峰值收缩速度和收缩期加速度的变化比较:术前明显低于正常参考值(P<0.05);术后1个月即高于术前,但差异不明显;术后6个月明显高于术前(P<0.05),但仍低于正常参考值犤术后6个月峰值收缩速度:(5.88±2.33),(5.83±2.79),(5.91±2.72),5.94cm/s;术后6个月收缩期加速度:(168.04±73.11),(162.67±69.97),(163.94±65.60),141.49cm/s2;术前峰值收缩速度:(4.01±2.45),(3.61±1.90),(4.22±2.50),4.85cm/s;术前收缩期加速度:(112.83±72.16),(99.70±70.40),(108.77±65.42),105.59cm/s2;峰值收缩速度正常参考值:(6.98±2.32),(6.53±2.57),(7.28±2.85),(6.54±2.03)m/s;收缩期加速度正常参考值:(183.47±75.98),(173.71±70.56),(182.01±78.46),(203.47±86.33)cm/s2犦。结论:①心肌节段缺血坏死时,局部的心肌收缩严重异常,导致病变节段室壁运动速度显著降低。②定量组织速度成像技术可定量、精确反映梗死心脏局部收缩运动,是一种无创、易重复的随访方式。     

血管紧张素转换酶基因分子变异与冠状动脉内支架再狭窄的相关性

目的:探讨血管紧张素转换酶(angiotensin-convertingenzyme,ACE)基因多态性与冠状动脉内支架再狭窄的相关性。方法:选择冠状动脉造影随访102例支架术后患者为研究对象,根据其ACE基因型分布不同分为II组39(例),ID例(44例),D组(19例);并D采用PCR法检测ACE基因插入/缺失(I/D)的多态性。结果:ACEI/D各基因型支架术前病变血管长度、参考血管直径等方面无差异;术前、术后即刻靶血管最小管腔直径也无差异,而术后6个月随访时靶血管管径晚期丧失参数,ACEI/D各基因型则存在显著性差异(t=3.83,P<0.05)。进一步的Posthoctests分析表明,II组术后随访时最小管腔直径、晚期丧失及净获得参数犤1.54±0.98),(1.45±0.96),(1.25±0.91)mm犦与DD组犤(0.90±0.87),(2.13±0.81),(0.54±0.91)mm犦比较,差异有显著性意义(P<0.05);而ID与DD组间及II与DD组间比较差异无显著性意义(P>0.05)。多因素回归分析表明靶血管最小管腔直径和ACEDD基因型是支架再狭窄的独立预测因子(P=0.004,0.018);其中ACEDD增加再狭窄的危险OR值为2.095(95%CI∶1.135～3.867)。结论:ACEDD基因型可能与冠状动脉内支架再狭窄具有相关性。     

面神经端侧吻合与端端吻合后神经再生质量的比较

目的:比较面神经损伤后端侧吻合与端端吻合方法效果。方法:在解放军总医院动物中心,用24只新西兰大耳白兔进行实验。左侧上颊神经切断后作端端吻合。右侧上颊神经切断后,远断端与下颊支侧方,外膜开窗处作支间端侧吻合。分别于术后1,2,3个月时作肌电图后取材,作组织学检查。结果:术后1,2个月时,端侧吻合肌电图神经传导速度慢于端端吻合犤1个月时(10.6±2.20),(15.7±2.13)m/s,2个月时(14.4±1.80),(20.80±3.10)m/s,P<0.05犦,术后3个月时端侧吻合肌电图神经传导速度与端端吻合差异无显著性意义犤(22.8±2.40),(23.20±2.14)m/s,P>0.05犦。术后1,2个月时,端侧吻合有髓神经纤维数少于端端吻合犤1个月时(34.16±4.24),(44.28±3.04)个/高倍视野,2个月时(43.64±3.20),(52.84±2.16)个/高倍视野,P<0.05犦,术后3个月时端侧吻合有髓神经纤维数与端端吻合差异无显著性意义犤(64.66±2.48),(66.12±1.96)个/高倍视野,P>0.05犦。结论:面神经断伤作端侧吻合后,早期神经再生质量不及端端吻合优良,晚期效果比较接近。     

冠状动脉内自体骨髓单个核细胞移植治疗心肌梗死后心力衰竭的临床观察

目的评价冠状动脉内自体骨髓单个核细胞移植治疗心肌梗死后心力衰竭的疗效及安全性。方法16例陈旧性心肌梗死至少3个月以上合并有心功能衰竭,心功能NYHA分级Ⅱ～Ⅳ级,左室射血分数(LVEF)<50%的患者,每例取自体单个核细胞(2.6±1.5)×107个注入冠状动脉,随访3～6个月,平均4.9个月。结果手术顺利,未见严重心律失常及炎症反应等不良反应;除1例第3个月时死于肺炎外,其余患者均健康存活,与术前比较NYHA心功能分级由3.0±0.5改善到2.2±0.6(P<0.05);6分钟步行试验由(292±78)m增加到(378±49)m(P<0.05);LVEF由(42±4)%提高到(46±8)%(P<0.05);左室壁运动积分(WMSI)由1.64±0.28降到1.34±0.33(P<0.05);核素心肌显像(SPECT)显示14例患者缺血范围不同程度缩小。结论冠状动脉内自体骨髓干细胞移植治疗心肌梗死后心功能衰竭安全、有效。     

骨质疏松症大鼠白细胞介素6、骨钙素和骨碱性磷酸酶的表达特征

背景白细胞介素6、骨钙素和骨碱性磷酸酶均参与骨代谢过程,其与骨质疏松的发生有相关性.目的观察白细胞介素6、骨钙素和骨碱性磷酸酶在骨质疏松大鼠中的表达特征.设计随机分组观察对比实验.单位深圳市人民医院(暨南大学医学院第二附属医院)骨科.材料实验于2002-01/2003-01在深圳市人民医院动物实验室及中心实验室完成.6月龄雌性SD大鼠60只,平均体质量250 g,随机分为3组去势组,对照组,空白组,每组20只.方法去势组手术切除大鼠双侧卵巢建立骨质疏松动物模型;对照组开腹后将卵巢提出腹腔后还纳关腹;空白组不行任何处理.分别于术后2,3,4,5,6个月后每组随机抽出大鼠4只,进行骨密度、骨钙素、白细胞介素6及碱性磷酸酶检测.主要观察指标大鼠全身骨密度、血清骨钙素、血清白细胞介素6及血清骨碱性磷酸酶变化.结果60只大鼠均进入结果分析.①大鼠骨密度测量结果4,5,6个月去势组骨密度较对照组和空白组明显下降[4个月(0.139 5±0.007 8),(0.147 0±0.000 8),(0.145 9±0.002 9)g/cm2,5个月(0.137 9±0.000 9),(0.145 6±0.000 8),(0.144 7±0.000 5)g/cm2,6个月(0.122 6±0.000 4),(0.145 0±0.002 1),(0.144 0±0.000 9)g/cm2,P＜0.05或＜0.01].②大鼠血清骨钙素测量结果4个月后去势组骨钙素显著高于对照组与空白组(P＞0.05).③大鼠白细胞介素6检测结果各时间点去势组白细胞介素6均显著高对照组与空白组(P＞0.05)④大鼠血清骨碱性磷酸酶4,5,6个月去势组骨碱性磷酸酶显著高于对照组与空白组[(2026±4)比(1247±12),(1291±7)nkat/L,(2342±9)比(1273±18),(1342±12)nkat/L,(2633±15)比(1340±9),(1357±8)nkat/L,P＜0.05]结论在骨质疏松症大鼠中骨密度显著降低,白细胞介素6、骨钙素和骨碱性磷酸酶在骨质疏松症大鼠中有显著表达,可作为骨质疏松症的诊断及筛查指标.     

超声心动图评价Dor法切除左心室室壁瘤术后对左心室形态和功能的影响

目的研究Dor法切除左心室室壁瘤术前、术后左心室二维形态的变化,了解该手术对左心室形态和功能的影响。方法采用Philips Sonos 5500超声诊断仪和S4探头,比较室壁瘤组(28例,治疗方法为Dor法合并或不合并冠状动脉搭桥术)和对照组冠心病无室壁瘤组(15例,治疗方法为仅行冠状动脉搭桥术)术前、术后心功能和二维形态指数的变化。结果室壁瘤组:手术死亡2例(7.1%);随访1~54月,平均(28.5±6.4)月,死亡2例(7.1%);存活患者左室射血分数从术前的0.37±0.09提高到术后的0.49±0.09(P<0.01);术后左心室形态更接近椭圆形,舒张末偏心指数从术前的0.57±0.12提高到术后的0.68±0.18(P<0.01),收缩末舒张末偏心指数从术前的0.63±0.15提高到术后的0.69±0.11(P<0.05)。对照组:随访4~19月,平均(11.2±4.6)月,无手术死亡和远期死亡,术前、术后左室射血分数和左心室形态无明显变化(P>0.05)。两组舒张末、收缩末偏心指数术后差别无显著性意义(P>0.05)。结论Dor法能有效改善左心室室壁瘤患者的心功能和心室形态。     

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.     

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.     

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.     

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.     

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.     

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.