Methodology and results of intravenous thrombolysis in acute myocardial infarction

For the vast majority of patients with acute myocardial infarction, intravenous thrombolysis is at present the only therapeutic approach aimed at early reperfusion of the ischemic myocardium. Rapid recanalization of the infarct-related coronary artery is achieved in at least 50–60% of the patients by short-term high-dose infusions of streptokinase or urokinase with a low risk of bleeding. A substantial reduction of infarct size, however, can be expected in only a minority of patients, mostly in those who are treated very early. The effects of intravenous thrombolysis on early and late mortality from acute myocardial infarction are still equivocal; more conclusive data may be expected from ongoing randomized trials.     

Intracoronary delivery of Gd-DTPA and Gadophrin-2 for determination of myocardial viability with MR imaging

The aim of this study was to compare intracoronary (i. c.) administration of Gadophrin-2, a necrosis-avid contrast agent (NACA), and nonspecific agent Gd-DTPA for determination of myocardial viability (MV) in acute myocardial infarction (AMI) with MRI. Reperfused AMI was induced in 12 dogs by transcatheter balloon occlusion of coronary artery. In 6 dogs each, Gd-DTPA at 0.1 mmol/kg or Gadophrin-2 at 0.005 mmol/kg was administered into coronary artery by fast bolus (n = 3) or slow infusion (n = 3). Serial ECG-triggered cardiac MRI of T1-weighted segmented turbo fast low-angle shot (FLASH) sequence was conducted and compared with triphenyltetrazolium chloride (TTC) histochemical staining. The contrast ratio and infarct size were quantified and analysed statistically. No cardiovascular side effects were found with local delivery of both agents. After i. c. administration, Gadophrin-2 induced a strong (CR ≥ 1.78) and persistent ( ≥ 10 h) contrast enhancement of infarcted region. The infarct size defined with Gadophrin-2 was almost identical to that with TTC staining throughout the postcontrast period. With a dose 20 times higher, Gd-DTPA also strongly enhanced infarct-to-normal contrast; however, the enhancement diminished with time, i. e. from early strong to later faint enhancement and eventual loss of contrast. The delineated infarct size was also unstable, i. e. from early overestimation to later underestimation and eventual disappearance of the enhanced infarct. In combination with PTCA procedure, i. c. administration of MRI contrast agents may prove useful for post-procedure verification of diagnosis. The NACA-enhanced MRI may serve as an in vivo surrogate of postmortem histochemical staining for determination of MV. Although applicable in clinical setting, cardiac MRI with nonspecific Gd-DTPA is less reliable and should be performed within less than 1 h after contrast. Received: 8 September 2000 Revised: 16 November 2000 Accepted: 21 November 2000     

急性心肌梗死心肌血流再灌注评价技术

TIMIFlow作为评价再灌注的方法自20世纪80年代起就一直应用于临床。TIMIFrameCount是较TIMI血流分级更为客观、更具可重复性的联系性变量指标。TMBG和TMP从心肌微血管水平对再灌注进行评价。冠脉内多普勒血流频谱变化常作为造影过程中的附加检查指标评价血管再通及心肌再灌注。同时心肌声学造影、连续心电图ST段监测、核素心肌灌注显像和心肌增强磁共振成像作为无创性的评价方法也显示出其应用价值。     

Role of technetium 99m methoxyisobutylisonitrile single photon emission tomography in the evaluation of thrombolysis in acute myocardial infarction before and after admission to hospital

To investigate initial perfusion status in acute myocardial infarction, methoxyisobutylisonitrile (MIBI) was administered by the rescue physicians. Thirty-nine patients received the radiopharmaceutical at home or upon arrival at the hospital. Diagnosis was confirmed in 30 patients, and 19 emergency thrombolyses were performed. Initial single photon emission tomography (SPET) analysis was constantly abnormal in confirmed myocardial infarction sometimes before direct electrocardiographic signs. MIBI-SPET was normal in non-coronary syndromes. MIBI uptake improved after thrombolysis (P < 0.001) but also after heparin therapy (P < 0.05). SPET improvement demonstrated myocardial salvage earlier than wall motion studies. MIBI administration at the patient's home allowed very early perfusion imaging when thrombolysis was performed at home. MIBI-SPET has the potential use of comparing thrombolytic agents or at home versus in hospital thrombolysis.for the Multicenter Study Group Etude MIBI (EMIBI)Members of the EMIBI Group     

ST段抬高急性心肌梗死早期静脉溶栓治疗的探讨

目的　探讨早期静脉溶栓治疗ST段抬高急性心肌梗死 (STEMI)的有效性与安全性。方法　回顾性分析 837例STEMI患者 ,早期静脉溶栓组 (n =5 0 2 )和对照组 (n =335 ,无溶栓指征或不愿溶栓者 ) ,观察早期静脉溶栓后梗死相关动脉 (IRA)的再通情况 ,同时分析两组住院期间心血管事件的发生率及药物不良反应。结果　早期静脉溶栓组梗死相关动脉 (IRA)的再通率为 6 0 .9% (rt PA组74 .2 % ,尿激酶组 5 7.6 % ) ,两组的不良反应无显著差异。住院期间两组患者在不稳定性心绞痛、非致命性再次心肌梗死、中风、非致命性心功能衰竭的发生率方面无明显差异 ,但溶栓组住院病死率较传统方法下降 17% ,且住院日显著缩短。结论　早期静脉溶栓是一种安全和有效的再灌注治疗的手段之一     

直接经皮冠脉介入和静脉溶栓治疗急性心肌梗死的比较

目的　探讨直接经皮冠脉介入 (PCI)和静脉溶栓治疗急性心肌梗死 (AMI)的临床疗效。方法　采用不同时期连续 13个月收治AMI患者 ,静脉溶栓组 5 7例 ,直接PCI组 75例。比较两组的再灌注率 ,以及两组住院和随诊期间心脏事件发生的情况。结果　静脉溶栓组再灌注率为 5 7.9% ,直接PCI组为 96 %。超声心动图LVEF值静脉溶栓组和直接PCI组分别为 0 .5 9± 0 .12和 0 .6 3± 0 .10。两组在住院期间的心脏事件的发生率无显著差异 ,而随访期间的心脏事件的发生率有显著差异 :直接PCI和静脉溶栓的不稳定心绞痛发生率分别为 9.3%和 38.6 % ;非致死性心功能衰竭 4 .0 %和 14 .0 % ;病死率 0 %和 7.0 % ;复合终点事件 9.3%和 5 0 .9%。结论　直接PCI能更快、更满意地开通梗死相关血管 ,抢救濒临死亡的心肌 ,改善心功能 ,降低病死率 ,优于静脉溶栓治疗。     

A case of acute myocardial infarction after intracoronary stent implantation: Demonstration of the stent location by postmortem X-ray examination

A 70-year-old man died 1 h after his car was involved in a minor collision with a stationary bus. One month before the accident, he had been diagnosed as having ischemic heart disease due to severe stenosis of the left anterior descending coronary artery (LADCA) by coronary angiography, followed by intracoronary stent implantation. Postmortem examination failed to show any potentially fatal injury, but macroscopic examination demonstrated myocardial necrosis accompanied by massive bleeding in the anterior left ventricle. Since it was difficult to delineate the precise site of the implanted stent in the heart by naked-eye examination, X-ray examination was performed. Guided by X-ray imaging, the stent, measuring 10 mm in length and 2 mm in diameter, was confirmed in the LADCA. Microscopic examination demonstrated myocardial necrosis accompanied by hemorrhage and granulation tissue in the anterior wall of the left ventricle, in the territory of the LADCA downstream from the implanted stent. However, there was no evidence of stent thrombosis. Therefore, it was likely that occlusion had occurred in a branch or branches of the LADCA downstream from the location of the stent. In conclusion, X-ray examination seems to be an effective adjunct in forensic pathology for localization of an implanted coronary stent and careful investigation of the coronary artery surrounding the stent.     

Teboroxime is a marker of reperfusion after myocardial infarction

Background  

It has been shown that serial teboroxime imaging can rapidly assess coronary perfusion in viable myocardial distributions. However, the myocardial uptake of teboroxime after reperfusion of acutely infarcted myocardium has not been critically evaluated. The study object was to assess whether teboroxime uptake in acutely infarcted myocardium is linearly related to blood flow.     

尿激酶溶栓治疗对急性心肌梗死患者QT离散度的影响

目的:观察尿激酶溶栓治疗对急性心肌梗死(AMI)患者QT离散度的影响。方法:对48例急性心肌梗死患者在发病6h内予以尿激酶溶栓治疗,比较AMI溶栓成功组与溶栓失败组治疗前后QT离散度(QTd)和QT离散度校正值(QTcd),比较各组溶栓前和溶栓治疗后7d内复杂室性心律失常(CVA)事件发生率。结果:AMI溶栓成功组治疗7d后QTd或QTcd较失败组显著减少(P<0.05),CVA事件的发生率显著低于溶栓失败组(P<0.05)。结论:尿激酶溶栓治疗可减小AMI患者的QTd或QTcd,减少CVA的发生,提高AMI患者的生存率。     

急性脑梗死两种溶栓治疗方法的安全性与疗效比较

 目的对比观察急性脑梗死(combinedintra-arterial,ACI)超早期行动静脉联合溶栓与静脉溶栓的临床疗效及安全性。方法系统性回顾分析68例行动静脉联合溶栓或静脉溶栓治疗的ACI患者的临床资料,比较两组术后闭塞血管再通率、术后NIHSS评分、并发症等。结果联合组、静脉组患者术后7d与术前相比,NIHSS评分差异均有统计学意义(P<0.05或P＜0.01)。两组患者术后24h、术后7dNIHSS评分相比,差异有统计学意义(P<0.05);两组患者术后闭塞血管再通率相比,差异有统计学意义(P<0.05);两组患者术后出血发生率及病死率相比,差异无统计学意义(P>0.5)。结论对于ACI的治疗,动静脉联合溶栓的疗效优于静脉溶栓。     

阿替普酶溶栓治疗ST段抬高型心肌梗死的临床评价

目的探讨阿替普酶（rt-PA）静脉溶栓治疗急性ST段抬高型心肌梗死的临床疗效和安全性。方法将我院2010年1月～2014年1月收治的126例ST段抬高型心肌梗死患者随机分为阿替普酶（rt-PA）组和尿激酶（UK）组,两组均在予阿斯匹林、氯吡格雷双联抗血小板、阿托伐他汀及其他常规治疗的基础上,分别给予阿替普酶及尿激酶溶栓治疗,比较两组总的冠脉开通率、胸痛缓解率、出血不良反应发生情况。结果 rt-PA组的冠脉再通率为79.4%,明显高于UK组的54.0%（P〈0.05）;rt-PA组的胸痛缓解率明显高于UK组（P〈0.05）,而出血不良反应明显低于UK组（P〈0.05）。结论阿替普酶溶栓治疗急性ST段抬高型心肌梗死,比尿激酶具有更高的冠脉开通率,临床疗效更佳,出血不良反应更少,安全性好,更适合基层医院推广使用。     

心血通胶囊对犬急性心肌缺血的影响

目的：观察收血通胶囊对实验性犬急性心肌缺血的影响,为进一步临床研究提供理论依据。方法：心血通胶囊经消化道给药后,采用心外膜标测和定量组织学硝基四氮唑蓝染色法,测定心肌梗塞范围及损伤程度。结果：心血中明显减轻由心外膜电图所标测的心肌缺血程度（∑－ＳＴ）及心肌缺血范围（Ｎ－ＳＴ）;明显减小通过Ｎ－ＳＴ染色所显示的梗塞区。结论：心血通对犬急性心肌缺血有明显的改善作用。     

缺血修饰白蛋白在急性心肌梗死早期诊断中的应用价值

目的：探讨血清缺血修饰白蛋白在急性心肌梗死早期诊断中的价值。方法：选择76例急性心肌梗死患者,分别于胸痛发作2、4、6、12、24、48 h采静脉血检测其缺血修饰白蛋白、CK、CK-MB及LDH的水平,查体表心电图,并与正常对照组比较,分析缺血修饰白蛋白对急性心肌梗死患者早期诊断的意义。结果：急性心肌梗死患者胸痛2、4、6 h缺血修饰白蛋白水平均明显高于正常对照组,差异有统计学意义（P〈0.05）,而胸痛12、24、48 h缺血修饰白蛋白水平与正常对照组比较,差异无统计学意义（P〉0.05）;胸痛2、4、6 h的缺血修饰白蛋白水平明显高于同组胸痛12、24、48 h,差异有统计学意义（P〈0.05）。与诊断急性心肌梗死的其他检查比较,缺血修饰白蛋白具有很好的相关性（P〈0.01）,更好的敏感性。结论：检测缺血修饰白蛋白的水平对于急性心肌梗死早期诊断及治疗有一定临床价值。     

Transplantation of progenitor cells after reperfused acute myocardial infarction: evaluation of perfusion and myocardial viability with FDG-PET and thallium SPECT

Clinical outcome after myocardial infarction depends on the extent of irreversibly damaged myocardium. Implantation of bone marrow-/circulating blood-derived progenitor cells has been shown to improve contractile cardiac function after myocardial infarction in both experimental and initial clinical studies. In the present study, first observations of the effect of local intracoronary progenitor cell infusion on the regeneration of infarcted cardiac tissue after acute myocardial infarction was evaluated by means of ¹⁸F-fluorodeoxyglucose positron emission tomography (PET) and ²⁰¹Tl single-photon emission computed tomography (SPECT). Twenty-six patients underwent intracoronary infusion of bone marrow-derived (BMCs) (15 patients) or circulating blood-derived endothelial progenitor cells (EPCs) (11 patients) 4±2 days after acute myocardial infarction. Based on a left ventricular segmentation model (17 segments), mean signal intensities as a parameter of viability and perfusion in the infarct zone and non-infarct areas were calculated quantitatively by PET and SPECT at baseline and at 4 months of follow-up. Transplantation of progenitor cells was associated with a significant increase in the mean signal intensity (MSI) in the infarct zone from 54.5% (25th and 75th percentiles: 47.7%, 60.0%) to 58.0% (52.7%, 66.7%) on PET (P=0.013) and from 58.0% (49.5%, 63.0%) to 61.5% (52.5%, 70.2%) on SPECT (P=0.005). Global left ventricular ejection fraction (LVEF) increased from 53.5% (42.6%, 60.0%) to 58.0% (53.0%, 65.8%) (P<0.001). In the five patients without an increase in MSI on PET, LVEF changed from 60.0% (50.0%, 64.0%) to 72.0% (64.0%, 75.5%) at follow-up. PET and SPECT did not show any significant changes in MSI in the non-infarct areas [from 73% (68.5%, 76.2%) to 73% (69.7%, 78.0%) for PET and from 72.0% (66.5%, 77.6%) to 73.0% (67.5%, 78.2%) for SPECT]. There were no significant differences in myocardial viability and perfusion between BMC and EPC infusion. These preliminary results show that coronary stenting and transplantation of progenitor cells result in a significant increase in myocardial viability and perfusion. Therapeutic effects can be reliably measured by PET and SPECT.     

不同救治手段对急性心肌梗死转归的影响

目的对比分析12h内来院的急性心肌梗死(AMI)患者采用溶栓,直接冠脉成形术和转院后急诊冠脉成形术治疗方法对AMI患者预后的影响。方法将2004年1月-2005年12月来院的AMI12h内患者采取连续入组的方式分为溶栓治疗组(32例)和直接冠脉成形术治疗组(63例),以及外院转院于12h内行急诊冠脉成形术治疗组(25例),比较3组患者在院期间和出院后1年转归的差别。结果与直接冠脉成形术和转院后急诊冠脉成形术相比,溶栓组到院至再通时间间隔最短,分别平均为(1.1±0.2)h、(2.3±1.0)h和(2.1±1.1)h,(P<0.01),病死率(分别为6.3%、3.2%和4.0%)和1年后病死率(分别为12.5%、4.8%和8.0%)均未达统计学意义,溶栓组非致死性再梗死的发生率显著高于PCI组(分别为18.8%和4.5%,P<0.05)。结论AMI的救治关键是尽早开通罪犯血管,转院治疗也是较为安全有效的治疗方式。     

Early detection of the no-reflow phenomenon in reperfused acute myocardial infarction using technetium-99m tetrofosmin imaging

Evaluation of myocardial perfusion in the early stage of acute myocardial infarction (MI) is clinically important for adjunctive therapies to minimize infarct size. To determine the role of early scintigraphic detection of impaired myocardial reperfusion after primary coronary angioplasty (PTCA) in patients with acute MI, semiquantitative technetium-99m tetrofosmin single-photon emission tomographic (SPET) imaging was performed before primary PTCA (before; area at risk), 60 min after PTCA (after) and at 1 month (1 M; final infarct) in 35 patients with acute MI. The left ventricle was divided into 13 segments and the defect score was calculated as the sum of the perfusion defect of each segment, from 3 (complete defect) to 0 (normal perfusion). A significant myocardial perfusion change after PTCA was defined as a change in the defect score (before minus after PTCA) of ≥4. The echocardiographic asynergic score was defined as the number of asynergic (severe hypokinetic or akinetic) segments corresponding to the analogous segments on SPET images, and recovery of wall motion was calculated as absolute change in the asynergic score (before PTCA minus 1 M). Among the 35 patients, 15 (43%) had a change in the defect score of <4 (no reflow: group 1) while 20 had a change in the defect score of ≥4 (reflow: group 2). There were no significant differences between the two groups with respect to the time between admission to PTCA, revascularization time, collateral grade or Thrombolysis in Myocardial Infarction (TIMI) flow grade before PTCA. Despite the lack of a difference in area at risk between the two groups (group 1 = 12.8±4.3 and group 2 = 15.1±4.7), final infarct size in group 1 was significantly larger compared with that in group 2 (8.1±4.3 vs 4.9±3.0, P<0.001). Recovery of wall motion was significantly smaller in group 1 than in group 2 (4.3±1.7 to 3.5±1.5 vs 4.1±2.1 to 1.6±1.6, P<0.001). In conclusion, a small change (<4) in defect score (scintigraphic no-reflow phenomenon) after primary PTCA indicates persisting impaired myocardial perfusion or irreversible cellular damage just after PTCA which is associated with poor recovery of wall motion, as compared with that observed in cases of reflow (≥4 in defect score). Received 12 September and in revised form 11 November 1998     

Exercise-rest Tc-99m tetrofosmin SPECT in patients with chronic ischemic left ventricular dysfunction: Direct comparison with Tl-201 reinjection

BACKGROUND: This study was designed to compare the results of exercise-rest technetium-99m tetrofosmin single photon emission computed tomography (SPECT) with those of thallium-201 reinjection at rest after exercise-redistribution imaging in the same patients with chronic ischemic left ventricular (LV) dysfunction. METHODS: Within 1 week, 33 patients with chronic myocardial infarction and LV dysfunction underwent exercise-rest tetrofosmin SPECT and Tl-201 reinjection at rest after exercise-redistribution imaging. In each patient, regional tetrofosmin and Tl-201 activity was quantitatively measured in 22 myocardial segments. Regional LV function was assessed in corresponding segments by echocardiography. RESULTS: Agreement in the evaluation of regional perfusion status between tetrofosmin and Tl-201 imaging was observed in 78% of the 726 total segments, with a kappa value of 0.61. In segments with normal function at echocardiography (n = 436), no difference between Tl-201 and tetrofosmin uptake was observed. In hypokinetic segments (n = 138), exercise tetrofosmin uptake was lower (P < .01) as compared with exercise Tl-201 activity, whereas no difference was observed between tetrofosmin uptake at rest as compared with Tl-201 activity on redistribution and reinjection images. In segments with severe functional impairment (akinetic or dyskinetic, n = 152), tetrofosmin uptake on exercise images was reduced (P < .01) as compared with exercise Tl-201 activity; furthermore, tetrofosmin uptake at rest was lower (P < .01) as compared with Tl-201 activity on both redistribution and reinjection images. In these segments, concordance in the detection of myocardial viability between tetrofosmin and Tl-201 imaging was observed in 138 (91%) of the 152 segments, with a kappa value of 0.77. CONCLUSIONS: In patients with chronic coronary artery disease and LV dysfunction quantitative exercise-rest tetrofosmin and Tl-201 reinjection SPECT provide similar information in the assessment of perfusion status and in the detection of myocardial viability.     

Prognostic value of adenosine Tl-201 myocardial perfusion imaging after acute myocardial infarction: Results of a prospective clinical trial

BACKGROUND: We have previously shown in retrospective studies that adenosine myocardial perfusion imaging (MPI) done after acute myocardial infarction (AMI) can effectively predict the risk of future cardiac events in these patients. The objective of this study was to validate these observations in a prospective clinical trial. METHODS AND RESULTS: One hundred twenty-six stable patients underwent quantitative adenosine MPI at a mean of 4.5 +/- 2.9 days after AMI. On the basis of the MPI results, they were divided into 3 risk groups: low risk (< 20% perfusion defect), intermediate risk (> or = 20% perfusion defect with < 10% ischemia), and high risk (> or = 20% perfusion defect with > 10% ischemia). The patients were followed up for 11 +/- 5 months for the occurrence of cardiac events: death, myocardial infarction, unstable angina, or congestive heart failure. The actual event rates correlated very well with the prespecified risk groups (19% for the low-risk group, 28% for the intermediate-risk group, and 78% for the high-risk group; P < .001). The significant multivariate predictors for events were female gender (relative risk [RR], 2.90; P = .002), left ventricular ejection fraction (RR, 1.34; P = .04), and ischemic defect size (RR, 1.46; P = .001), with a global chi2 value of 26.7. CONCLUSION: This study demonstrates, in a prospectively designed clinical trial, that quantitative adenosine MPI performed soon after AMI can effectively predict the risk of future cardiac events. These findings are currently being validated in an ongoing, large, multicenter, international clinical trial.     

动脉溶栓与机械碎栓联合动脉溶栓的对比分析

目的 比较两种不同动脉溶栓方法治疗超早期脑梗死患者的疗效,探讨哪种方法更有益于开通血管.方法 收集2009年10月- 2011年5月55例脑梗死急性期并行超早期介入治疗患者,其中25例(联合治疗组)采用机械碎栓联合尿激酶进行动脉内溶栓治疗,30例(尿激酶组)采用尿激酶进行单纯动脉内溶栓治疗.术后观察患者闭塞血管再通和神经功能障碍恢复情况,并比较分析两种动脉溶栓方法的疗效.结果 联合治疗组患者血管再通23例,成功再通率为92%(23/25),尿激酶组患者则为18例,再通成功率仅为60%(18/30).术后平均NIHSS(脑卒中量表)及ADL(日常活动量表)评分联合治疗组(1 h 分别为8.6 ± 2.5和20.0 ± 4.6;24 h分别为9.0 ± 1.8和17.0 ± 2.5)改善程度明显优于尿激酶组(1 h分别为7.5 ± 2.0和28.0 ± 3.5;24 h分别为8.1 ± 2.0和24.0 ± 2.1),两组间差异有统计学意义(P ＜ 0.05).尿激酶用量及溶栓时间联合治疗组分别为(36.8 ± 8.4)万u和(35.3 ± 11.6)min,尿激酶组分别为(50.4 ± 15.3)万u和(55.7 ± 13.3)min,前者低于后者,两组间差异有统计学意义(P ＜ 0.05).结论 超早期应用动脉内机械碎栓联合动脉溶栓治疗急性脑梗死的疗效优于单纯动脉溶栓.