急性心肌梗死患者血清肌钙蛋白I浓度的释放特点及其对静脉溶栓再通的判定价值

目的　观察急性心肌梗死 (AMI)接受静脉溶栓治疗患者血清肌钙蛋白Ⅰ (cTnⅠ )的浓度变化情况及其评价溶栓再通的价值。　方法　 6 6例AMI者均接受静脉溶栓治疗 ,应用ELISA法测定cTnⅠ值。　结果　溶栓再通组 5 2例 ,溶栓未通组 14例 ,两组的cTnⅠ释放大部分存在双峰 ,溶栓再通组第一峰时 (11 34小时± 3 30小时 )、第二峰时 (2 3 80小时± 12 4 3小时 )比未通组相对应的时间明显提前 (P <0 0 5 ) ,cTnⅠ第一峰时比CK MB峰时提前。以cTnⅠ第一峰值到达时间≤ 14小时判定溶栓再通的敏感性、特异性及准确性分别为 92 31%、6 4 2 9%及6 6 5 %。　结论　在大多数AMI者血清cTnⅠ释放呈双峰 ,其第一、二峰值到达时间在溶栓再通组前移 ,血清cTnⅠ≤ 14小时作为评价溶栓再通与否 ,有一定的判定价值     

溶栓治疗对急性心肌梗死患者血浆内皮素和一氧化氮水平的影响

目的 :探讨溶栓治疗对急性心肌梗死 (AMI)患者内皮素 (ET)和一氧化氮 (NO)水平的影响。方法 :治疗组 32例 ,采用尿激酶 15 0万U于 6 0min内静脉滴注 ,分别测出治疗前及治疗后溶栓再通组 (18例 )和未通组 (14例 )ET和NO水平的动态变化。对照组 2 0例 ,测治疗前ET和NO水平。结果 :①治疗组的ET水平高于对照组 (P <0 .0 5 ) ,NO水平低于对照组 (P <0 .0 5 ) ;②溶栓再通组的ET、NO水平显著增高 ,峰值分别是 196 .2 8± 2 0 .14ng/L和5 6 .82± 13 .6 2 μmol/L ,显著高于溶栓未通组的峰值 (ET 112 .18± 15 .2 2ng/L和NO43.87± 10 .12 μmol/L ,P <0 .0 5 ) ;③再通组ET和NO峰值提前 ,都在溶栓后 2h ,而溶栓未通组ET和NO峰值均为溶栓后 6h。结论 :①ET/NO代谢失衡是构成AMI发生的一个重要机制 ;②溶栓后NO水平升高可拮抗再灌注损伤引起的ET水平增高。     

血清肌钙蛋白T及I对急性心肌梗死早期诊断的临床价值

目的 :观察急性心肌梗死 (AMI)患者入院前后血清肌钙蛋白T(cTnT)、肌钙蛋白I(cTnI)的变化 ,探讨cTnT、cTnI对早期诊断AMI的价值。方法 :对 10 0例患者 (AMI 5 0例、不稳定型心绞痛 5 0例 )和 2 0例健康人进行了血清cTnT、cTnI、肌酸激酶 (CK)和肌酸激酶同工酶 (CK MB)检测。结果 :①血清cTnT、cTnI、CK和CK MB检测AMI的敏感度和特异度分别为 80 %和 90 %、85 %和 92 %、92 %和 6 1%、75 %和 75 %。②AMI患者血清cTnT、cTnI浓度平均升高 (17.5± 5 .7)和 (16 .2± 4 .8)倍 ,显著高于CK(7.6± 3.1)倍、CK MB (6 .5± 2 .9)倍 (P <0 .0 1) ;③AMI后 3h内cTnT、cTnI阳性检出率为 5 0 .0 %、4 0 .0 % ,明显高于CK MB(2 4 .0 % )和CK(2 0 .0 % ) ;AMI 5d后cTnT、cTnI阳性检出率为 70 .0 %、6 6 .0 % ,而CK MB和CK仅为 4 .0 %和 8.0 %。结论 :血清cTnT、cTnI能早期确切诊断AMI ,具有较宽的时间诊断窗口 ,是心肌梗死早期诊断较敏感和特异的血清标志物     

肌钙蛋白T对急性心肌梗死静脉溶栓疗效的判断价值

105例患者采用尿激酶天普乐欣150万～200万U/半小时内静脉溶栓。结果:再通组CK、CK-MB及TnT峰值时间(小时)分别为12.46±1.16、11.75±1.29及12.66±1.37,明显早于未通组(P<0.001)。上三项峰值浓度仅TnT值(μg)再通组(14.145±2.6110)显著高于未通组(8.673±1.616),p<0.05。峰值相对浓度再通组与未通组TnT显著高于CK-MB(P<0.001)。以TnT早期峰时≤16h,TnT 12h/24 h≥1.0及TnT 12h/24h≥0.8作为判断溶栓再通的的指标。表1     

曲美他嗪对急性心肌梗死溶栓再通患者的心肌保护作用

目的探讨曲美他嗪对急性心肌梗死溶栓再通患者的心肌保护作用.方法68例因急性心肌梗死而行早期静脉溶栓的患者随机分为曲美他嗪组(T组)和对照组(C组),T组在常规治疗的基础上于溶栓前后给予曲美他嗪口服,C组不用曲美他嗪.比较两组再通患者间肌酸激酶(CK)峰值浓度、CK恢复正常的时间、再灌注心律失常及2周后的左室功能.结果(1)T组和C组溶栓再通患者分别为24例和23例,两组临床基线资料无统计学差异.(2)T组CK和CK-MB峰值浓度分别为(1265±728)和(114±67)U/L,显著低于C组的(1739±814)和(159±72)U/L(P＜0.05);T组CK及CKMB峰值时间和恢复正常的时间均显著短于C组(P＜0.05或0.01).(3)T组33%(8例)发生再灌注心律失常,显著低于C组的65%(15例)(P＜0.05).(4)2周后超声心动图检测的左室射血分数T组为(58±10)%,显著高于C组的(51±10)%(P＜0.05);室壁运动指数T组为1.25±0.23,显著低于C组的1.43±0.25(P＜0.05).结论对溶栓再通的急性心肌梗死患者,曲美他嗪可能缩小梗死面积,减轻再灌注损伤,保护心脏功能.     

急性心肌梗塞早期溶栓治疗前后QT间期离散度变化

探讨急性心肌梗塞溶栓治疗前后QT间期离散度 (QTintervaldispersion ,QTd)的变化 ,我们将 34例施溶栓治疗的急性心肌梗塞 (acutemyocardialinfarction ,AMI)病人分为 2组 :再通组 18例 ,未通组 16例。测定溶栓前及溶栓后 2、8、2 4、4 8h和 1周的同步 12导联心电图QTd。溶栓前再通组与未通组QTd分别为 :58.3± 13.5ms ,56.2± 17.1ms ;溶栓后再通组与未通组QTd分别为 :2h ,70 .2± 14.2ms ,58.5± 13.1ms ;8h ,51.2± 13.6ms ,73.4± 15.8ms ;2 4h ,4 8.7± 16.8ms,66.5± 15.2ms ;4 8h ,4 0 .5± 11.8,66.5± 15.2 ;1周 ,38.6± 13.4 ,50 .1± 15.8。溶栓后 ,再通组与未通组QTd各对应时间段相比 ,有显著性差异 (P <0 .0 1)。溶栓前再通组与未通组QTd相比无显著性差异 (P >0 .0 5)。说明成功的溶栓治疗使心室复极的QTd缩短 ,使QTd最高值提前出现。QTd缩短速度明显加快 ,对于判断溶栓治疗的疗效有一定意义     

急性心肌梗死溶栓时间对血管再通和近期预后的影响

目的研究急性心肌梗死发病后不同时间溶栓治疗对血管再通和预后的影响.方法根据溶栓时间将64例分成≤4h,＞4～6h和＞6～12h三组,比较血管再通率、再通所需时间及对近期预后的影响.结果血管再通率分别为73%,66.2%,49.4%(后者与前二组相比差异有显著性,P＜0.05);血管再通所需时间与发病至溶栓的时间呈正相关,分别为58.9±32.1min,89.4±28.5min和109.1±30.2min(P＜0.05).室性心律失常和心绞痛的发生率以基本通畅组为最高(P＜0.01),病死率以未通组为最高(P＜0.01).结论急性心肌梗死发病6h以内血管再通效果最好,及时有效再灌注有利于改善急性心肌梗死患者的近期预后.     

急性心肌梗死溶栓后降钙素基因相关肽和内皮素的变化

目的 :探讨急性心肌梗死 (AMI)患者溶栓后降钙素基因相关肽 (CGRP)和内皮素(ET)的变化。方法 :将 4 5例AMI患者根据溶栓情况分为常规治疗组、溶栓未通组和溶栓再通组 ,用放射免疫法测定 3组患者梗死后不同时间 (4、6、8、10、12、14、2 4、16 8h)的血浆CGRP和ET水平。结果 :溶栓再通组血浆CGRP和ET峰值显著高于常规治疗组和溶栓未通组 (P <0 .0 1) ,且峰值出现时间提前 2h。结论 :AMI患者溶栓再通后CGRP和ET峰值提高 ,且时间提前 ,CGRP和ET可作为溶栓再通和评价梗死范围的一种有价值的指标。     

四种新的心肌损伤标记物在急性心肌梗死早期诊断中的比较研究

目的 :探讨新的生化标记物对急性心肌梗死 (AMI)早期诊断价值。　　方法 :动态监测 98例AMI患者血清肌红蛋白 (Mb) ,心肌肌钙蛋白I、T (cTnI、cTnT )及肌酸激酶MB同工酶(CK MB)的变化 ,对比分析它们对AMI的早期诊断及对预后的判断。　　结果 :AMI起病 6小时之内 ,以Mb诊断敏感性最高 (90 2 0 % ) ,cTnI次之 (5 2 94% ) ,CK MB最低 (2 7 45 % ) ;cTnI和cTnT升高显著且较长时间不降者预后差。　　结论 :早期确诊或排除AMI以cTnI和Mb组合更为可取 ;判断溶栓是否再通以cTnI和CK MB更为准确可靠 ;对那些心肌损伤标记物升高显著 ,且较长时间居高不降者 ,提示预后欠佳。     

静脉溶栓治疗对急性心肌梗死患者QT间期离散度及室性心律失常的影响

目的　研究静脉溶栓心肌再灌注治疗对急性心肌梗死 (AMI)患者QT间期离散度(QTd)与校正的QT间期离散度 (QTcd)及室性心律失常 (VA)恶性程度的影响。方法　分别于入院时及溶栓治疗后 4周记录 15例溶栓成功及 17例溶栓未成功患者常规 12导联心电图 ,计算QTd及QTcd ,并行心电监测 ,记录住院期间发生的VA。结果　再通组 (15例 ) 4周后QTd与QTcd[(5 2 .9± 10 .4)ms、(5 8.7± 12 .3 )ms]与溶栓前QTd与QTcd比较 [(69.7± 15 .5 )ms ,(80 .5± 2 7.0 )ms]显著减小 (P <0 .0 5 )。 4周后再通组较溶栓失败冠脉未通组 (17例 )QTd与QTcd[(63 .7±15 .5 )ms ,(72 .3± 2 5 .4)ms]显著减小 (P <0 .0 5 )。再通组VA恶性程度与未通组比较有显著降低 ,死亡率亦降低。结论　早期静脉溶栓成功心肌再灌注治疗可以显著减小心肌梗死患者的QT间期离散度 ,并降低室性心律失常的恶性程度     

Comparison of five cardiac markers in the detection of reperfusion after thrombolysis in acute myocardial infarction.

OBJECTIVE--To investigate and compare the clinical usefulness of serial measurements of five cardiac marker proteins, namely creatine kinase (CK), CK-MB mass, myoglobin, troponin T, and myosin light chain 1, in the early detection of reperfusion after thrombolytic treatment. METHOD--Serial blood samples were taken from 26 patients presenting with acute myocardial infarction. Concentrations of the five markers were assayed in each sample. Thrombolytic treatment was given to the patients who were divided into those who reperfused (n = 17, group A) and those who failed to reperfuse (n = 9, group B) on the basis of clinical signs and angiography within 24 h. RESULTS--The release profiles of CK, CK-MB mass, myoglobin, and troponin T for patients in group A differed from those of patients in group B. No difference was observed in the release profile of myosin light chain 1 between the two groups. The time to peak concentration of CK, CK-MB mass, myoglobin, and troponin T occurred significantly earlier in patients of group A than in those of group B, with myoglobin peaking earlier than the other markers. An index, defined as the ratio of the concentration of each marker immediately before and 2 h after the start of thrombolytic treatment, was calculated for each marker in groups A and B. The 2 h myoglobin and troponin T indices were significantly different between groups A and B. The diagnostic efficiency of the myoglobin index, however, was best at 85%. CONCLUSIONS--These studies suggest that myoglobin has greater potential than the other markers examined in the detection of reperfusion after thrombolytic treatment.     

Time course of serum cardiac enzymes after intracoronary thrombolytic therapy. Creatine kinase, creatine kinase MB isozyme, lactate dehydrogenase, and serum glutamic-oxaloacetic transaminase

We analyzed the time course of serum creatine kinase (CK), the CK MB isozyme, lactate dehydrogenase (LDH), and serum glutamic-oxaloacetic transaminase (SGOT) activity and calculated rates of increase and decline for CK in 24 consecutive patients with acute myocardial infarction (AMI) who received intracoronary thrombolytic therapy. In 19 patients with successfully reperfused infarcts, peak CK activity occurred at 14.1 +/- 1.1 hours after onset of symptoms, the maximal rate of CK rise was 595 +/- 102 IU/L/hr, and the fractional disappearance rate (Kd) was (86 +/- 6) X 10(-5)/min. The peak CK MB activity occurred at 12.9 +/- 0.8 hours and the MB Kd was (223 +/- 39) X 10(-5)/min. In five patients in the nonreperfused group the peak CK (24.9 +/- 4.5 hours) and CK MB (22.7 +/- 3.3 hours) activity occurred later, the maximal rate of CK rise (281 +/- 37 IU/L/hr) was less, and the CK Kd [(68 +/- 5) X 10(-5)/min] and MB Kd [(116 +/- 28) X 10(-5)/min] were lower. The peak CK, CK MB, cumulative CK release, and area under the curve were not different. Except for a shortened time to peak SGOT in the reperfused (17.1 +/- 1.3 hours) compared with the nonreperfused (29.1 +/- 5.6 hours) groups, the time course of LDH and SGOT were not different. Thus, the initial serum CK kinetics and time to peak SGOT may be useful in assessing the reperfusion status in patients with AMI receiving thrombolytic therapy without coronary angiography or in those who may have spontaneous recanalization.     

Peak creatine kinase as a measure of effectiveness of thrombolytic therapy in acute myocardial infarction

As part of the National Heart, Lung, and Blood Institute multicenter Thrombolysis in Myocardial Infarction Trial, the time to peak plasma creatine kinase (CK) activity as a marker of reperfusion in 272 patients with validated acute myocardial infarction was analyzed. Patients were treated with either tissue-type plasminogen activator or streptokinase by intravenous administration. All patients underwent acute coronary angiography. The infarct-related artery was identified and thrombolytic therapy administered. Reperfusion at 90 minutes was documented by angiography. CK was determined before institution of therapy and every 4 hours thereafter for the first 24 hours. Patients were classified into 3 groups for comparative purposes: group 1--occlusion with no reperfusion (n = 119); group 2--occlusion with reperfusion (n = 98); and group 3--subtotal occlusion (n = 55). Early (within 4 hours after treatment) and late (more than 16 hours after treatment) peaking of CK differentiated patients with drug-induced perfusion from those without reperfusion. Although peak CK between 5 and 11 hours after drug treatment did suggest perfusion through the infarct-related artery, it did not differentiate between drug-induced and spontaneous reperfusion. Clinically, early peak CK is a useful noninvasive means of assessing coronary artery patency. However, in clinical trials assessing drug therapy, the use of peak CK may overestimate drug effectiveness by including patients with spontaneous reperfusion.     

心脏肌钙蛋白T在急性心肌梗死中的应用价值

目的 探讨血清肌钙蛋白T(cTnT)在急性心肌梗死(AMI)后的释放特点及其对AMI溶栓后的疗效判定。方法 采用酶联免疫法对28例AMI患者进行动态血清cTnT观察,同时测定CK及CK-MB。结果 溶栓2小时阳性率为67.9％、发病8小时至5天为100％、发病7、9、11、13、15、17、19天分别为92.9％、82.1％、67、9％、60.7％、39.3％、21.4％、7.1％。明显比CK和CK-MB持续时间长。cTnT诊断急性心肌梗死的敏感性为100％。溶性再通组15例呈双峰曲线,4例呈单峰曲线,双峰者首峰与次峰比大于2,单峰都在24小时以内出现。未通组双峰3例,单峰6例,双峰者首峰与次峰比不大于2,单峰多在4～5天内出现。把首峰与次峰之比(或第24小时内峰值与第4日峰值之比)大于2,作为溶栓再通指标的敏感性为89.5％,特异性为100％。结论 血清中cTnT动态变化对AMI的诊断及溶栓治疗效果的评定均有一定的价值。     

Indices of reperfusion in patients with acute myocardial infarction using characteristics of the CK-MB time-activity curve

The purpose of this study was to identify indices of coronary artery reperfusion in patients treated with thrombolytic therapy for acute myocardial infarction (AMI) by means of characteristics from the serum creatine kinase (CK) isoenzyme MB time-activity curve. Frequent blood sampling as performed in three groups with a first AMI: 29 patients treated with intravenous thrombolytic therapy who had a patent infarct-related artery with normal flow (TIMI-3) at acute catheterization (reperfusion group); four patients with a persistently closed infarct-related artery (no reperfusion group); and 44 patients who did not receive any therapy aimed at coronary reperfusion (no thrombolytic therapy group). In the latter group we prospectively estimated that 25% would have spontaneous reperfusion. A physiologically based computer-calculated multi-compartment method was used to determine the characteristics of the serum CK-MB time-activity curve. In addition to demonstrating an earlier increase, a shorter time to peak of serum CK-MB and a lower estimated infarct size in the reperfusion group (p = 0.025 to 0.00001), the appearance rate constant (k1) and time from estimated initial increase to peak of CK-MB in the blood stream (tRP) were significantly different from those values in the no thrombolytic therapy group (p less than 00001). A cutoff level indicating reperfusion if k1 was greater than 0.185 or tRP was less than 16.5 hours demonstrated overlapping values between these two groups in only four patients (k1), two patients (tRP), and six patients with a combination.(ABSTRACT TRUNCATED AT 250 WORDS)     

Influence of reperfusion therapy on left ventricular remodeling after acute myocardial infarction

To determine the relation between reperfusion therapy and left ventricular function and remodeling after acute myocardial infarction (AMI), 75 consecutive patients with anterior AMI were studied. The patients were divided into four groups according to the reperfusion outcome and time to reperfusion from onset of MI: 12 patients with spontaneous reperfusion, 18 patients with early (less than 4th) successful reperfusion, 16 patients with late (greater than or equal to 4th) successful reperfusion and 29 patients with unsuccessful reperfusion. The right oblique left ventriculograms (LVG), which was performed early (n = 19) and late after infarction (n = 75) were analyzed to assess left ventricular (LV) volume and global and regional LV function. At the late examination, spontaneous early and late reperfused patients showed smaller LV volume (endo diastolic and endo-systolic volume index) than unsuccessfully reperfused patients LV volume was similar in both early and late reperfused patients. Spontaneous and early reperfused patients showed higher LV ejection fraction (EF) and better regional wall motion (RWM) than unsuccessfully reperfused patients. Both EF and RWM was similar in late and unsuccessfully reperfused patients at the late examination. Endo-diastolic and endo-systolic volume index increased significantly with time in patients with unsuccessful reperfusion (n = 10), as compared with the index found in the early examination. In patients with late reperfusion (n = 5), end-diastolic volume index increased with time, but end-systolic volume index was unchanged. RMW improved in patients with early reperfusion (n = 4), but was unchanged in patients with late and unsuccessful reperfusion.(ABSTRACT TRUNCATED AT 250 WORDS)     

Prognostic implications of an early peak in plasma MB creatine kinase in patients with acute myocardial infarction

To determine the prognostic implications of an early peak in plasma MB creatine kinase (MB CK) in patients with acute myocardial infarction who were not treated with an acute intervention, 342 patients with myocardial infarction confirmed by MB CK were retrospectively studied. The patients were classified into those with an early peak MB CK (less than or equal to 15 hours after the onset of symptoms, n = 84) and those with a late peak MB CK (greater than 15 hours after the onset of symptoms, n = 258). Patients with an early peak MB CK were slightly older, were more frequently female and had a higher incidence of prior myocardial infarction, congestive heart failure and arrhythmias compared with patients with a late peak MB CK. Patients with an early peak MB CK more frequently presented with ST segment depression (23 versus 11%, p less than 0.01), with anterior location of ischemia or infarction (71 versus 52%, p less than 0.01) and with a lower mean left ventricular ejection fraction (41.4 versus 47.4%, p less than 0.01). Despite more extensive left ventricular dysfunction at initial presentation, patients with an early peak MB CK had a smaller mean MB CK infarct size index (12.6 versus 18.9 g-Eq/m2, p less than 0.01), with no difference in the incidence of in-hospital complications, including death. The early left ventricular dysfunction improved in the patients with an early peak MB CK, evidenced by a 4.5% increase in ejection fraction from admission to 10 days after infarction, whereas the ejection fraction did not improve in patients with a late peak MB CK. However, the patients with an early peaking MB CK had myocardium in jeopardy as reflected by a higher incidence of ST segment depression and a decrement in the global left ventricular ejection fraction with exercise. The 4 year life table estimate for the rate of recurrent myocardial infarction after hospital discharge was higher in patients with an early peak MB CK (33 versus 22%, p less than 0.05), with an even more striking difference in the 4 year estimate for the rate of fatal recurrent infarction (20 versus 8%, p less than 0.001). The 4 year mortality estimate was markedly higher in hospital survivors with an early peak MB CK than in those with a late peak (47 versus 19%, p less than 0.0001) and, even after adjustment for differences in baseline characteristics, the residual excess mortality in those with an early peak was still significant (p less than 0.02).(ABSTRACT TRUNCATED AT 400 WORDS)     

Detection of coronary artery reperfusion with creatine kinase-MB determinations during thrombolytic therapy: correlation with acute angiography

Increases in plasma creatine kinase-MB (MB CK) were correlated with the onset of coronary artery reperfusion determined angiographically in 32 patients with acute myocardial infarction who were treated with recombinant human tissue-type plasminogen activator (rt-PA). Reperfusion occurred in 14 (70%) of 20 patients with left anterior descending coronary artery occlusion and in 8 (73%) of 11 patients with right coronary artery occlusion. One patient had persistent left circumflex coronary artery occlusion. Plasma MB CK levels (radioimmunometric assay) did not increase significantly in patients with persistent occlusion, but increased by a mean (+/- SEM) of 8 +/- 1 and 6 +/- 1 times over pretreatment levels at the end of the infusion in patients with a reperfused left anterior descending and right coronary artery, respectively. When a greater than or equal to 2.5-fold increase in MB CK levels at the end of the rt-PA infusion was taken as evidence of reperfusion of the left anterior descending coronary artery, 13 (93%) of 14 patients with reperfusion and 5 (83%) of 6 with persistent occlusion were correctly identified. When a greater than or equal to 2.2-fold increase in MB CK levels was used to identify right coronary artery reperfusion, seven (89%) of eight patients with persistent occlusion were correctly identified. The sensitivity and specificity of these indexes, derived from and applied to the same patient group, were 91 and 89%, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)     

Early noninvasive detection of successful reperfusion in patients with acute myocardial infarction

Myoglobin (Mb) is a protein that enters rapidly and is rapidly cleared from plasma after coronary reperfusion. We sought to determine the accuracy with which a rapid rise in plasma [Mb] could predict successful coronary artery reopening in patients undergoing coronary arteriography in conjunction with attempted reperfusion in acute myocardial infarction. In 42 patients, plasma Mb levels were measured before and for at least 4 hours after attempted reperfusion. Thirty-five patients were successfully reperfused. In each, the plasma Mb level rose rapidly with peak [Mb] occurring at 111 +/- 8.1 (+/- SEM) minutes after application of therapy. In contrast, Mb levels rose more slowly in the seven patients who were not reperfused, with peak [Mb] occurring 360 +/- 61.4 minutes after attempted reperfusion. T25-100 (the time required for [Mb] to rise from 25% to 100% of peak value) was shorter in patients successfully reperfused (71 +/- 7.9 minutes) and longer (341 +/- 35.3 minutes) in patients in whom therapy was unsuccessful. A rapid rise in [Mb] after successful reperfusion was also evident by a more than 4.6-fold rise in [Mb] over the first 2 hours after reperfusion in all but five patients; in contrast, [Mb] rose by less than 4.6-fold over this same interval in every patient not successfully reperfused (sensitivity, 85%; specificity, 100%; predictive accuracy, 88%). We conclude that a rapid rise in plasma Mb level over the initial 2 hours after attempted reperfusion in acute myocardial infarction provides a useful index of successful reperfusion.