急性心肌梗死后存活心肌对梗死相关血管晚期血运重建术后左室功能的影响

目的探讨存活心肌对急性心肌梗死(AMI)后梗死相关血管(IRA)晚期血运重建术后远期左室功能以及左室重构的影响.方法69例AMI未接受早期再灌注治疗者,于发病10～21 d行IRA经皮冠状动脉血运重建(PCI)术,术前于AMI发病后5～10 d应用小剂量多巴酚丁胺(5和10μg·min-1·kg-1)超声心动图负荷试验检测存活心肌,并分别测定和计算给药前后左室腔大小、左室射血分数(LVEF)以及室壁运动积分(WMS).按有无存活心肌分为存活心肌组和无存活心肌组,超声心动图随访术后6个月时两组左室腔大小、LVEF和WMS的变化.结果157个运动异常节段中89个节段(57%)有存活心肌,有存活心肌组26例(占38%),无存活心肌组43例(占62%).存活心肌组术后6个月LVEF较术前明显提高(P＜0.05),收缩末期容积指数(LVESVI)和WMS明显降低(P＜0.05和P＜0.01);而无存活心肌组LVEF较术前明显降低(P＜0.01),LVESVI和左室舒张末期容积指数(LVEDVI)较术前明显增加(P＜0.05),WMS无明显变化.存活心肌组多巴酚丁胺负荷时的LVEF和WMS明显改善,且与6个月时的测定值相近;而无存活心肌组PCI前应用多巴酚丁胺LVEF和WMS均无明显变化.结论AMI后有存活心肌者晚期血运重建有利于改善远期左室功能和减少左室重构.心肌梗死后早期小剂量多巴酚丁胺负荷状态下左室收缩功能的提高预示晚期血运重建术后心功能改善.     

磁共振成像特征追踪技术测定左心室应变与急性心肌梗死透壁程度关系

目的应用基于心脏磁共振成像(MRI)电影序列的特征追踪技术分析急性心肌梗死患者左心室心肌应变,探索其与急性心肌梗死透壁程度的关系,及急诊经皮冠状动脉介入治疗(PCI)术后心肌应变演变规律。方法入组74例急性ST段抬高型心肌梗死(STEMI)患者,均于急性心肌梗死12 h内接受急诊PCI,术后2~5 d,行心电门控稳态自由进动序列扫描采集电影序列图像,同时行钆对比剂延迟强化,得到短轴强化序列图像。其中20例3~5月后复查MRI。应用Tom Tec 2D CPA软件分析电影序列,得到局部心肌应变指标,(包括各节段内膜圆周、径向、纵向应变峰值),和整体心肌应变指标(包括整体圆周、径向、纵向应变值),应用Segment分析软件计算延迟强化序列各个节段心肌梗死透壁程度。结果本研究74例STEMI患者,梗死面积为(11.81±7.28)%。分析得到537个无梗死节段,425个非透壁梗死节段,182个透壁梗死节段。圆周应变峰值基底段无梗死节段(–23.90±10.92)%、非透壁梗死节段(–18.94±10.51)%、透壁梗死节段(–14.24±9.05)%,两两比较发现,无梗死节段指标(取绝对值)显著高于非透壁梗死节段(P=0.000),非透壁梗死节段指标显著高于透壁梗死节段(P=0.016)。圆周应变峰值中间段无梗死节段(–22.13±9.98)%、非透壁梗死节段(–17.47±8.72)%、透壁梗死节段(–12.71±8.92)%,两两比较发现,无梗死节段指标(取绝对值)显著高于非透壁梗死节段(P=0.000),非透壁梗死节段指标显著高于透壁梗死节段(P=0.000)。圆周应变峰值心尖段无梗死节段(–22.46±10.31)%、非透壁梗死节段(–19.51±12.49)%、透壁梗死节段(–13.81±11.13)%,两两比较发现,透壁梗死节段指标(取绝对值)显著低于无梗死节段(P=0.000)与非透壁梗死节段(P=0.001),但无梗死节段与非透壁梗死节段指标比较,差异无统计学意义。纵向应变峰值在基底段与中间段,无梗死节段、非透壁梗死节段及透壁梗死节段指标比较,差异无统计学意义;但心尖段三个阶段指标分别是(–20.26±12.42)%,(–14.82±11.29)%,(–11.94±9.73)%,两两比较发现,无梗死节段指标(取绝对值)显著高于非透壁梗死节段(P=0.000),非透壁梗死节段显著高于透壁梗死节段(P=0.043)。径向应变峰值在基底段无梗死节段(31.92±17.47)%与非透壁梗死节段(22.35±18.57)%比较,差异有统计学意义(P=0.000),与透壁梗死节段(17.78±16.24)%比较,差异有统计学意义(P=0.000),但非透壁梗死节段与透壁梗死节段比较,差异无统计学意义。径向应变峰值在中间段无梗死节段(32.13±16.37)%、非透壁梗死节段(25.20±15.85)%、透壁梗死节段(15.20±10.48)%,两两比较发现,无梗死节段指标显著高于非透壁梗死节段(P=0.000),非透壁梗死节段指标显著高于透壁梗死节段(P=0.000)。径向应变峰值心尖段无梗死节段(27.42±14.94)%与非透壁梗死节段(20.51±15.43)%比较,差异有统计学意义(P=0.001),与透壁梗死节段(16.59±11.84)%比较,差异有统计学意义(P=0.000),但非透壁梗死节段与透壁梗死节段比较,差异无统计学意义。20例患者PCI术后无梗死节段、非透壁梗死节段、透壁梗死节段圆周应变、纵向应变及径向应变达峰值均较急性心肌梗死时有升高趋势。其中非透壁梗死节段圆周应变(取绝对值)及纵向应变(取绝对值)较PCI术前升高[(–16.88±9.92)%比(–19.46±11.31)%,P=0.018;(–12.02±9.46)%比(–16.67±11.29)%,P=0.000];透壁梗死节段圆周应变(取绝对值)及径向应变较PCI术前升高[(–13.83±9.47)%比(17.20±10.63)%,P=0.035;(18.36±12.85)%比(24.55±14.81)%,P=0.001],差异均有统计学意义。结论急诊PCI术后STEMI患者,在急性期局部心肌应变在无梗死节段、非透壁梗死节段、透壁梗死节段之间有差别。PCI术后3~5个月,非透壁梗死节段圆周应变及纵向应变较急性期时改善,而透壁梗死节段圆周应变及径向应变改善。心脏磁共振成像特征追踪技术与钆对比剂延迟技术相结合,可从功能学和组织学特征两方面对急性心肌梗死心肌损伤综合评估。     

AMI患者PCI后心肌灌注水平对心功能及左室重构的影响

目的:探讨急性心肌梗死（AMI）患者经皮冠脉介入术（PCI）后TIMI血流III级时的心肌灌注水平及其对心功能与左室重构的影响。方法: 对36例AMI患者PCI后行经静脉心肌声学造影（MCE）和心脏二维超声检查。①利用心肌声学造影评分（MCS）及室壁运动评分(WMS)分析PCI后心肌灌注情况与室壁运动情况的关系;②根据声学造影积分指数（CSI）将患者分为A、B两组,比较两组的左室射血分数（LVEF）,评估心肌灌注水平对心功能的影响;③根据心脏二维超声结果,比较两组患者术后6个月时左室舒张末直径（LVEDD）及LVEF的变化,进一步评估心肌灌注水平对左室重构的影响。结果: PCI后梗死相关血管TIMI血流均达III级。共152节段与梗死相关血管的再灌注有关。①MCS为0分的18节段中,2个（11.1%）WMS为1~2分;MCS为0.5分的30节段中16个（53.3 %）WMS为1~2分;MCS为1分的104节段中,82个（78.8%）WMS为1~2分;统计学分析显示,PCI后心肌灌注水平与室壁运动呈正相关（P<0.05）。②心肌灌注好的A组LVEF显著大于B组［(52.1±3.4)%,(47.2±2.9)%,P<0.05］。③术后6个月A组的LVEF及LVEDD均无明显变化,B组的LVEF较前有所下降［(47.2±2.9)%,(43.8±4.4)%,P<0.05］,LVEDD较前有所增加［(50.2±2.9) mm,(56.3±3.1) mm,P<0.05］。结论: AMI患者PCI后心肌灌注水平与心功能及左室重构有一定相关性,良好的心肌灌注在一定程度上可以抑制左室重构。     

心肌梗死区存活心肌对糖尿病急性心肌梗死患者PCI术后心功能的影响(英文)

目的:探讨糖尿病急性心肌梗死经皮冠状动脉介入治疗(PCI)术后患者心肌梗死区存活心肌对左室重构及左心功能的影响。方法:208例2型糖尿病并急性心肌梗死PCI术后的患者接受静息状态下18-氟脱氧葡萄糖正电子发射断层扫描术(18F-FDG PET)心肌代谢显像与99m锝-甲氧基异丁基异腈单光子发射型计算机断层成像术(99Tcm-MIBI SPECT)心肌灌注显像,根据心肌梗死区有无存活心肌,分为有心肌存活组(115例,灌注-代谢不匹配)和无心肌存活组(93例,灌注一代谢匹配)。检测两组PCI术前、术后超声心动图各指标,观察心肌梗死区心肌存活状态对于左室重构以及心功能的影响。结果:心肌梗死12个月后有存活心肌组左室射血分数(LVEF)显著高于无存活心肌组[(46.7±6.98)%比(44.1±7.12)%],左室舒张末期内径(LVEDd)[(53.17±4.77)mm比(55.46±4.75)mm],左房内径[(35.89±12.08)mm比(39.25±11.31)mm]显著小于无存活心肌组,P均<0.05。舒张期二尖瓣血流速度峰值的比值12个月后两组无显著差异(P>0.05)。结论:于2型糖尿病合并急性心肌梗死的患者,心肌梗死区有存活心肌患者较无心肌存活患者,LVEF明显改善,左室舒张末期内径显著缩小。     

急性心肌梗死行PCI术患者联合血栓抽吸与替罗非班治疗的疗效及对cTnT水平的影响

目的:探讨重症急性心肌梗死(AMI)行皮冠脉介入治疗(PCI)患者联合应用血栓抽吸及替罗非班治疗的效果及对心肌肌钙蛋白T(cTnT)水平的影响。方法:我院ICU治疗的AMI患者108例,随机分为单纯PCI组和联合治疗组(PCI术中接受血栓抽吸联合替罗非班),各54例,比较两组的治疗效果及血清cTnT水平变化。结果:与单纯PCI组比较,联合治疗组术后90 min的TIMI血流改善率(77.78%比94.44%)和ST段回落率(72.22%比90.74%)均显著提高(P均0.05);术后30d的左室射血分数[(46.34±0.53)%比(53.41±0.32)%]显著提高,左室舒张末期内径显著减小[(6.02±0.32)cm比(5.34±0.22)cm],3个月内MACE发生率(20.37%比3.70%)显著降低,P均0.01;术后3d,两组血清cTnT水平均较术前显著降低,且联合治疗组cTnT水平显著低于单纯PCI组[(0.19±0.05)ng/ml比(0.32±0.03)ng/ml],P=0.001。结论:重症急性心肌梗死患者PCI术中联合应用血栓抽吸及替罗非班治疗,可显著改善患者梗死相关动脉血流及心功能,减轻心肌损伤程度,降低MACE发生率。     

急诊和择期经皮冠状动脉介入术后心肌修复情况的比较

目的探讨急诊和择期经皮冠状动脉介入(PCI)术后心肌的修复情况。方法回顾性分析2018年1月至2019年2月广安市人民医院心血管内科住院的心肌梗死患者97例,根据行PCI术时机分为急诊PCI术组50例和择期PCI术组47例,术后3个月通过心脏磁共振成像(CMRI)评估和比较2组患者心功能和心肌修复情况,并比较术前和术后3个月肌钙蛋白I(TnI)、脑钠肽(BNP)和肌酸激酶同工酶MB(CK-MB)水平。应用SPSS 19.0统计软件对数据进行分析,根据数据类型采用t检验或χ~2检验进行组间比较。相关性采用Pearson相关分析。结果 2组患者PCI术后3个月较术前左心室舒张末期容积(LVEDV)、左心室收缩末期容积(LVESV)、梗死心肌质量、梗死心肌容积视觉评分、室壁运动异常评分、TnI、BNP和CK-MB均改善,且急诊PCI术组相比择期PCI术组患者水平低[(108.41±21.15)和(126.61±22.05)ml;(59.55±14.41)和(65.54±11.64)ml;(6.84±2.15)和(9.16±3.00)g;(6.03±2.11)和(8.15±2.32)分;(3.01±1.16)和(4.41±1.25)分;(106.84±29.98)和(122.16±32.11)g/L;(1.00±0.34)和(1.24±0.54)ng/L;(32.21±5.44)和(35.49±4.48)U/L],差异均有统计学意义(P0.05)。Pearson相关分析结果表明,梗死心肌质量与梗死心肌容积视觉评分、室壁运动异常评分、LVEDV、LVESV正相关(r=0.411、0.354、0.306和0.341,P0.05)。结论急诊PCI术可显著改善心肌梗死患者心肌的功能和修复。     

缺血预适应对急性心肌梗死患者PTCA术后左室功能和近期预后的影响

目的探讨缺血预适应(IPC)对急性心肌梗死(AMI)患者经皮冠状动脉腔内成形术(PTCA)后左室功能和近期临床预后的影响.方法将40例成功实施PTCA的初次AMI患者按是否并发梗死前心绞痛(PA)分为二组:PA( )组23例,患者在梗死前24h内至少有1次心绞痛发作;PA(-)组17例,梗死前无心绞痛史.应用超声心动图观察PTCA术前及术后2周射血分数(LVEF)、左室短轴缩短分数(LVES)、左室舒张末容积(LVEDV)以及左室收缩末容积(LVESV)的变化.统计PTCA后2周内心脏事件的发生率.结果①二组患者在PTCA前的LVEDV、LVESV、LVEF及LVFS差异均无统计学意义(P＞0.05);②PTCA术后2周,PA( )组LVEDV及LVESV明显缩小(P＜0.01,0.05),LVEF及LVFS显著提高(P＜0.05,0.01).PA(-)组术后LVEDV、LVESV及LVFS均达到明显改善,但手术前后LVEF无明显变化(P＞0.05);③PTCA术后2周,二组患者各指标进行组间比较,PA( )组LVEDV[(101.0±27.1)比(122.7±26.3)ml,P＜0.05]及LEVSV[(50.1±27.0)比(70.2±26.7)ml,P＜0.05]缩小程度PA(-)组明显,LVEF[(57.4±13.6)比(46.1±12.6)%,P＜0.05]及LVFS[(34.7±4.8)比(27.8±4.1)%,P＜0.01]提高的程度显著高于PA(-)组;④二组住院病死率、再发心绞痛及再梗死的发生率无差别(P＞0.05),但PA( )组心功能不全(13.0%比41.2%,P＜0.05)与严重心律失常(17.4%比47.1%,P＜0.05)的发生率显著低于PA(-)组.结论缺血预适应可以使AMI患者在PTCA术后左室重构过程中保存较好的泵功能,并改善术后短期临床预后.     

直接经皮冠状动脉介入术中球囊充盈次数对心肌灌注和心肌坏死程度的影响

目的 探讨直接经皮冠状动脉介入术(PCI)中球囊充盈次数与心肌灌注和心肌坏死程度的关系,评价缺血后适应在直接PCI中可能的临床效果.方法 回顾分析2004年1月至2006年12月于我院行直接PCI的ST段抬高性心肌梗死(STEMI)患者140例,梗死相关血管(IRA)为左前降支(LAD)或右冠状动脉(RCA),术前IRA血流为TIMI 0级,且无侧支循环充盈,术后TIMI血流达3级.排除心搏骤停复苏后、心源性休克、曾患心肌梗死或有梗死前心绞痛的患者.按直接PCI中球囊充盈次数将患者分为A组(球囊充盈次数为1～2次者)和B组(球囊充盈次数为3次或以上者),其中A组62例,B组78例.直接PCI后心肌灌注情况用心肌Blush分级和ST段恢复情况来评价,心肌坏死程度用心肌酶[肌酸激酶(CK),肌酸激酶同工酶(CK-MB)]释放峰值水平和出院前超声心动图测得左室射血分数(LVEF)来评价.结果 两组患者基本临床特征相似,PCI中球囊充盈次数B组显著高于A组(4.7±0.9比1.8±0.2,P＜0.05).PCI术后造影示心肌Blush分级B组(2.35±0.32)明显高于A组(1.89±0.29),P＜0.05.两组患者入院时心电图最大ST段抬高幅度相似,分别为4.53±0.62 mm(A组)和4.31±0.58 mm(B组)(P＞0.05),术后2 h最大ST段抬高幅度分别降至1.65±0.49 mm和0.98±0.37 mm(P＜0.05).B组患者CK及CK-MB峰值水平均显著低于A组(1 368±726 U/L比1 976±869 U/L,P＜0.05;132±76 U/L比189±84 U/L,P＜0.05).出院前B组LVEF(54.76%±11.24%)明显高于A组(47.68%±10.17%,P＜0.05).结论 直接PCI术中需多次球囊充盈的患者较最少球囊充盈次数的患者心肌灌注改善、心肌坏死程度减轻,提示多次球囊充盈以断续的方式来解除持续性心肌缺血可能模拟了缺血后适应的心脏保护作用.     

急性ST段抬高型心肌梗死急诊介入治疗前应用替罗非班对疗效的影响

目的 前瞻性比较急诊室或导管室应用替罗非班对急诊冠状动脉介入治疗(PCI)急性ST段抬高型心肌梗死(STEMI)临床疗效的影响.方法 入选连续113例接受急诊PCI治疗的急性STEMI患者,随机分为急诊室内(术前使用组,56例)和导管室内替罗非班使用组(术中使用组,57例).比较两组基础临床情况、介入治疗结果、术后30天和180天主要心脏不良事件(MACE,死亡/再梗死/再次靶血管重建)发生率及左室射血分数(LVEF).结果 两组基础临床情况差异无统计学意义.与术中使用组相比,术前使用组急诊PCI术前梗死相关动脉TIMI 3级复流血流发生率明显增高(23.2%比8.8%,P＜0.05).术后校正TIMI帧数(cTFC)显著降低(20.2±4.7帧比23.1±5.3帧,P＜0.01),但TIMI 3级(96.4%比94.7%,P＞0.05)、TMP 3级(64.3%比57.9%,P＞0.05)、ST段总和回落(6.2±1.2 mm比6.0±1.1mm,P＞0.05)、肌酸激酶混合型同工酶(CK-MB)峰值(229.5±97.1 ng/mL比247.9±78.8 ag/mL,P＞0.05)、肌钙蛋白(Tn)I峰值(67.7±31.0 ng/mL比74.6±32.8 ng/mL,P＞0.05)、平均住院天数(12.7±6.2 d比12.0±4.5 d,P＞0.05)差异均无统计学意义.术后30天和180天术前使用组MACE发生率分别降低49%和32%、左室射血分数分别增加4.3%和3.6%(P均＞0.05).Kaplan-Meier生存分析显示,两组术后30天(96.4%比93%,P＞0.05)和180天(92.9%比89.5%,P＞0.05)无MACE生存率差异无统计学意义.术前使用组出血并发症发生率低于术中使用组(10.7%比12.3%,P＞0.05).结论 急诊室内早期应用替罗非班能显著提高急性STEMI患者急诊PCI术前梗死相关动脉开通率和术后心肌灌注,但近期临床预后与导管室内使用该药组的差异无统计学意义.     

阿托伐他汀对CHD患者PCI术后血清hsCRP、IL-17、APN水平及心功能的影响

目的:研究阿托伐他汀对冠心病(CHD)患者经皮冠状动脉介入治疗(PCI)术后血清高敏C反应蛋白(hsCRP)、白细胞介素(IL)-17、脂联素(APN)水平及心功能的影响。方法:2015年5月～2016年3月于我院接受PCI治疗的CHD患者168例被随机分为常规治疗组(80例)和阿托伐他汀组(在常规治疗组基础上接受阿托伐他汀,88例)。观察比较两组治疗前、治疗1个月后、治疗2个月后血清hsCRP、IL-17、APN水平、LVEF、左室收缩末期容积指数(LVESVI)及左室舒张末期容积指数(LVEDVI)。结果:与常规治疗组比较,阿托伐他汀组治疗1、2个月后血清hsCRP[2个月:(4.61±1.39)μg/ml比(2.69±0.78)μg/ml]、IL-17[2个月:(151.13±17.37)μg/ml比(103.95±15.37)μg/ml]水平、LVESVI[2个月:(34.25±6.44) ml/m~2比(21.75±4.86)ml/m~2]、LVEDVI[2个月:(59.03±5.05) ml/m~2比(43.18±4.75)ml/m~2]依次显著降低,血清APN水平[2个月:(6.17±1.09) mg/L比(8.46±1.53)mg/L]、LVEF[2个月:(49.96±8.81)%比(62.85±8.92)%]依次显著升高(P均=0.001)。结论:阿托伐他汀能显著改善CHD患者PCI术后心功能,降低血清hsCRP、IL-17水平,升高血清APN水平。     

Anaerobic myocardial abscess following myocardial infarction

An anaerobic myocardial abscess due to Bacteroides fragilis developed in a 60-year-old man when he had an acute myocardial infarction while recuperating from surgery for a paracolonic abscess. Anaerobic bacteremia is a common event and may lead to infection in areas of low oxygen tension far removed from the original portal of entry.     

曲尼司特对心肌梗死后心肌间质纤维化的影响

目的探讨曲尼司特对兔心肌梗死后心肌间质纤维化干预作用。方法结扎左前降支制作兔心肌梗死模型,分实验组和对照组。3周后经胃管分别给予曲尼司特及安慰剂1月,心脏彩超评价心功能并检测血清转化生长因子（transform ing growth factor,TGF-β1）,I、III型胶原浓度及组织羟脯胺酸含量。结果实验组治疗前后心功能、心腔内径、室壁厚度明显改善,血清TGF-β1,I、III型胶原浓度及羟脯胺酸含量较对照组明显下降。结论曲尼司特可有效拮抗心肌梗死后心肌间质纤维化,预防心室重构。     

Transient myocardial ischaemia after acute myocardial infarction

The prevalence and characteristics of transient myocardial ischaemia were studied in 203 patients with recent acute myocardial infarction by both early (6.4 days) and late (38 days) ambulatory monitoring of the ST segment. Transient ST segment depression was much commoner during late (32% patients) than early (14%) monitoring. Most transient ischaemia (greater than 85% episodes) was silent and 80% of patients had only silent episodes. During late monitoring painful ST depression was accompanied by greater ST depression and tended to occur at a higher heart rate. Late transient ischaemia showed a diurnal distribution, occurred at a higher initial heart rate, and was more often accompanied by a further increase in heart rate than early ischaemia. Thus in the first 2 months after myocardial infarction transient ischaemia became increasingly common and more closely associated with increased myocardial oxygen demand. Because transient ischaemic episodes during early and late ambulatory monitoring have dissimilar characteristics they may also have different pathophysiologies and prognostic implications.     

Assessment of myocardial viability using myocardial contrast echocardiography

Myocardial contrast echocardiography (MCE) is a technique that uses microbubbles as a tracer during simultaneous ultrasound of the heart. The microbubbles can be used to provide quantitative information regarding the adequacy of myocardial blood flow (MBF), as well as the spatial extent of microvascular integrity. In acute myocardial infarction, MCE can identify the presence of collateral flow within the risk area, and can therefore predict preservation of myocardial viability and ultimate infarct size even prior to reperfusion. After reperfusion, the extent of microvascular no-reflow can be determined, and has significant implications for recovery of left ventricular function. In chronic ischemic heart disease, MCE has also been shown to successfully differentiate viable from necrotic myocardium. This technique can accurately predict recovery of function after revascularization. More importantly, MCE can be used to identify viable segments that may help to prevent infarct expansion and remodeling, and thus improve patient outcomes.     

Assessment of myocardial viability with myocardial contrast echocardiography

The application of noninvasive imaging techniques to assess myocardial viability has become an important part of routine management of patients with acute myocardial infarction and chronic coronary artery disease. Information regarding the presence and extent of viability may help identify patients likely to benefit from revascularization or therapy directed at attenuating left ventricular remodeling. Myocardial contrast echocardiography (MCE) is capable of defining the presence and extent of viability by providing an accurate assessment of microvascular integrity needed to maintain myocellular viability. It is especially suited for the spatial assessment of perfusion, even when myocardial blood flow is reduced substantially in the presence of severe epicardial stenoses or in a bed dependent on collateral perfusion. The routine use of MCE to evaluate viability in patients with acute and chronic coronary artery disease is now feasible with the advent of new imaging technologies and microbubble agents capable of myocardial opacification from venous injections. The utility of this technique for determining treatment strategies has not been established but is forthcoming.     

经静脉心肌声学造影评价心肌梗死后存活心肌的价值

目的　探讨经静脉心肌声学造影 (MCE)对心肌梗死后存活心肌的诊断价值。方法　 2 4例心肌梗死患者用二维超声评价室壁运动情况 ,同时经静脉进行MCE ,以 3个月后静态超声心动图左室心肌节段性运动改善为依据评价MCE对心肌梗死后存活心肌的诊断价值。结果　在 2 4例病人的 384个心肌节段中 ,运动异常节段 184个。在运动异常的 184个节段中 ,MCE1分 39段 ,0 5分 5 0段 ,0分 95段。 3个月复查 79个节段有运动改善 ,其中 39段来自MCE1分的心肌 ,4 0段来自MCE0 5分的心肌。MCE对预测心肌梗死后室壁运动改善的敏感性、特异性、阳性预测值、阴性预测值及准确率分别为 :10 0 %、89 7%、84 8%、10 0 %和 94 6 %。结论　MCE能比较准确地预测心肌梗死后心肌的存活性     

Transient myocardial ischaemia after acute myocardial infarction.

The prevalence and characteristics of transient myocardial ischaemia were studied in 203 patients with recent acute myocardial infarction by both early (6.4 days) and late (38 days) ambulatory monitoring of the ST segment. Transient ST segment depression was much commoner during late (32% patients) than early (14%) monitoring. Most transient ischaemia (greater than 85% episodes) was silent and 80% of patients had only silent episodes. During late monitoring painful ST depression was accompanied by greater ST depression and tended to occur at a higher heart rate. Late transient ischaemia showed a diurnal distribution, occurred at a higher initial heart rate, and was more often accompanied by a further increase in heart rate than early ischaemia. Thus in the first 2 months after myocardial infarction transient ischaemia became increasingly common and more closely associated with increased myocardial oxygen demand. Because transient ischaemic episodes during early and late ambulatory monitoring have dissimilar characteristics they may also have different pathophysiologies and prognostic implications.