补救性冠状动脉成形术治疗老年人急性心肌梗死

目的 评价老年人急性心肌梗死（AMI）溶栓失败后补救性冠状动脉成形术（PCTA）的成功率。住院存活率及6个月随访结果。方法 28例老年人AMI,于发病（胸痛）开始6h内接受静脉溶栓治疗,溶栓开始90min时行冠状动脉造影,示TIMI（心肌梗死溶栓试验）血流0-1级或虽达2级但仍有胸痛,立即给予急诊补救性PTCA并记录其成功率、住院存活率,术后随访6个月。结果 全部患者中梗塞相关动脉（IRA）31支,其中前降支病变17支,右冠状动脉病变10支,回旋支病变4支,补救性PTCA使26例患者IRA完全再通,成功率92.9%,TIMI血流均达3级,其中10例补救性PTCA后因残余狭窄大于50%而植入支架。成功的补救性PTCA患者住院存活率96.3%,1例死亡,术后随访6个月,4例因胸痛复发经冠状动脉造影证实为再狭窄（15.4%）。未成功的补救性PTCA患者中1例死亡（死亡率50%）。结论 老年人AMI溶栓失败后补救性PTCA成功率及住院存活率高,远期预后良好。     

延迟性冠脉介入及静脉溶栓对急性心肌梗死预后的影响

目的:对比研究延迟经皮冠状动脉内成形术(PTCA)及支架植入术(ICS)与静脉溶栓术(IT)对急性心肌梗死(AMI)患者近期及远期预后的影响。方法:36例初次AMI患者被分为2组,即延迟PCI组(A组)16例、静脉溶栓成功组(B组)20例。结果:(1)住院期间A组和B组平均住院天数(d)、再发不稳定心绞痛(％)、非致死心肌梗死(％)、心源性死亡(％)、住院期死亡及复合终点事件(不稳定性心绞痛、心肌梗死和死亡的总和)(％)、室壁运动异常积分指数等指标之间比较无明显差异(P>0.05);(2)随访期间A组左室扩大(％)、室壁瘤形成(％)、死亡及复合终点事件(％)、再狭窄率(％)等发生率低于B组(P<0.05)、存活率(％)及射血分数(％)明显高于B组(P<0.05)。结论:失去溶栓时机或溶栓失败的AMI患者积极行延迟PTCA及支架植入治疗,对改善近期及远期预后是有益的。     

Stenting versus thrombolysis in acute myocardial infarction trial (STAT)

OBJECTIVES: We sought to directly compare primary stenting with accelerated tissue plasminogen activator (t-PA) in patients presenting with acute ST-elevation myocardial infarction (AMI). BACKGROUND: Thrombolysis remains the standard therapy for AMI. However, at some institutions primary angioplasty is favored. Randomized trials have shown that primary angioplasty is equal or superior to thrombolysis, while recent studies demonstrate that stent implantation improves the results of primary angioplasty. METHODS: Patients presenting with AMI were randomly assigned to primary stenting (n = 62) or accelerated t-PA (n = 61). The primary end point was the composite of death, reinfarction, stroke or repeat target vessel revascularization (TVR) for ischemia at six months. RESULTS: The primary end point was significantly reduced in the stent group compared with the accelerated t-PA group, 24.2% versus 55.7% (p < 0.001). The event rates for other outcomes in the stent group versus the t-PA group were as follows: mortality: 4.8% versus 3.3% (p = 1.00); reinfarction: 6.5% versus 16.4% (p = 0.096); stroke: 1.6% versus 4.9% (p = 0.36); recurrent unstable ischemia: 9.7% versus 26.2% (p = 0.03) and repeat TVR for ischemia: 14.5% versus 49.2% (p < 0.001). The median length of the initial hospitalization was four days in the stent group and seven days in the t-PA group (p < 0.001). CONCLUSIONS: Compared with accelerated t-PA, primary stenting reduces death, reinfarction, stroke or repeat TVR for ischemia. In centers where facilities and experienced interventionists are available, primary stenting offers an attractive alternative to thrombolysis.     

Primary angioplasty versus systemic thrombolysis in anterior myocardial infarction

OBJECTIVES: This study compares the efficacy of primary angioplasty and systemic thrombolysis with t-PA in reducing the in-hospital mortality of patients with anterior AMI. BACKGROUND: Controversy still exists about the relative benefit of primary angioplasty over thrombolysis as treatment for AMI. METHODS: Two-hundred and twenty patients with anterior AMI were randomly assigned in our institution to primary angioplasty (109 patients) or systemic thrombolysis with accelerated t-PA (111 patients) within the first five hours from the onset of symptoms. RESULTS: Baseline characteristics were similar in both groups. Primary angioplasty was independently associated with a lower in-hospital mortality (2.8% vs. 10.8%, p = 0.02, adjusted odds ratio 0.23, 95% confidence interval 0.06 to 0.85). During hospitalization, patients treated by angioplasty had a lower frequency of postinfarction angina or positive stress test (11.9% vs. 25.2%, p = 0.01) and less frequently underwent percutaneous or surgical revascularization after the initial treatment (22.0% vs. 47.7%, p < 0.001) than did patients treated by t-PA. At six month follow-up, patients treated by angioplasty had a lower cumulative rate of death (4.6% vs. 11.7%, p = 0.05) and revascularization (31.2% vs. 55.9%, p < 0.001) than those treated by t-PA. CONCLUSIONS: In centers with an experienced and readily available interventional team, primary angioplasty is superior to t-PA for the treatment of anterior AMI.     

Percutaneous transluminal coronary angioplasty versus thrombolysis in acute myocardial infarction: A meta-analysis

While percutaneous transluminal coronary angioplasty (PTCA) as a primary modality for treating acute myocardial infarction (MI) has been shown to have important advantages over thrombolysis, a survival benefit has not been demonstrated because of the small size of the individual trials. To increase the statistical power to detect a survival benefit, we performed a meta-analysis of trials of PTCA and thrombolysis. We pooled the data for all randomized, controlled trials; randomized, controlled trials stratified according to thrombolytic agent [streptokinase vs. tissue plasminogen activator (TPA)]; and all trials. Pooling was performed by calculating the Mantel-Haenszel odds ratio with the Robins, Greenland, and Breslow estimate of variance. Calculation of the Q statistic was performed to assess heterogeneity. For all four analyses, the odds ratio indicated a significant survival advantage of PTCA over thrombolysis: all randomized controlled trials [0.57,95% confidence index (CI): 0.48,0.68)]; streptokinase trials [0.61,95% CI: 0.43,0.87); TPA trials (0.52,95% CI: 0.36,0.76); all trials (0.51,95% CI: 0.43,0.61). The Q statistic was not significant for any of the analyses. The results of our meta-analysis support the hypothesis that PTCA is associated with a significant reduction in mortality compared with thrombolysis.     

Systemic thrombolysis and percutaneous transluminal coronary angioplasty (PTCA) in acute myocardial infarction

Intravenous high-dose infusion of streptokinase in acute evolving myocardial infarction is a widely used therapeutic concept with clinically relevant recanalization rates and low complications. In our experience with 150 patients and acute myocardial infarction treated with intravenous streptokinase (1.5 Mio U), 107 (78 p. 100) of 137 patients demonstrated an antegrade perfused infarct artery. In a group of patients (n = 95), in whom early revascularization was performed, the incidence of reinfarction was reduced from 15 p. 100 to 7 p. 100; hospital mortality was not influenced (3.6 p. 100 vs 4.3 p. 100). PTCA was successful in 39 of 48 patients (81 p. 100). The incidence of angiographically determined restenosis amounted to 28 p. 100 (9/32). Patients after successful PTCA without restenosis demonstrated an improvement of left ventricular function in contrast to patients with restenosis or reocclusions. Thus, intravenous streptokinase followed by PTCA presents a clinically practicable and promising method for treatment of acute myocardial infarction.     

Heparin management in acute myocardial infarction (AMI)

Antithrombotic agents have been shown to be beneficial in the setting of acute coronary syndromes, and as an adjunct to thrombolysis for acute myocardial infarction (AMI). The optimal type and dosing of antithrombotic drug, however, remains elusive. Heparin, the agent most commonly used, has several limitations, the most important of which may be its inability to inhibit clot-bound thrombin. Newer, direct thrombin inhibitors (such as hirudin) provide potent and predictable thrombin inhibition and are able to inhibit clot-bound thrombin. Both heparin and hirudin can carry a substantial risk of haemorrhage, however, and thrombin activity is likely to rebound after discontinuation of either agent. Further, the relationships of antithrombotic/thrombolytic dosing, measures of anticoagulation (such as APTT), and clinical outcomes are not always clear. Nonetheless, from the data available from large, randomised trials, intravenous heparin should remain a standard adjunct to thrombolytic therapy for AMI.     

Combined Abciximab REteplase Stent Study in acute myocardial infarction (CARESS in AMI)

Background

Most patients with acute myocardial infarction (AMI) are admitted to hospitals without percutaneous transluminal coronary angioplasty (PTCA) facilities or are initially managed in a prehospital mobile unit. Thrombolysis remains the most readily available reperfusion treatment in those settings, but the optimal subsequent strategy in those patients is unclear. If a mechanical recanalization is likely to be performed in an emergency, it is probably desirable that the patient receives abciximab, the glycoprotein IIb/IIIa antagonist with the strongest evidence of benefit for angioplasty in AMI.

Objective

The aim of this trial is to compare the effects on clinical outcome and cost-effectiveness of 2 strategies after immediate treatment with abciximab and half-dose reteplase for ST-elevation AMI: to manage the patients conservatively (referring them for rescue PTCA only if needed) or to immediately send all patients for emergency coronary angioplasty.

Methods

The Combined Abciximab RE-teplase Stent Study in Acute Myocardial Infarction (CARESS in AMI) is an open, prospective, randomized, multicenter clinical trial conducted in patients with high-risk ST-segment elevation AMI treated within 12 hours from symptom onset in hospitals without PTCA facilities or in a prehospital mobile intensive care unit. Apart from contraindications to thrombolysis, the main exclusion criteria are age ≥75 years and a past history of CABG surgery or a percutaneous coronary intervention procedure involving the infarct-related artery. Enrollment will be performed in hospitals without PTCA facilities or directly in the ambulance if a dedicated system is in place for prehospital diagnosis and treatment of AMI. Patients will receive half-dose reteplase and full-dose abciximab and will subsequently be randomized to conventional medical therapy (with referral for emergency rescue PTCA allowed in selected cases) or emergency angioplasty. The primary end point is the 30-day combined incidence of mortality, reinfarction, and refractory ischemia. In order to obtain a 95% power (2-sided) to detect a 42% reduction in the primary end point, 900 patients are required in each arm of the study. Secondary end points include the 1-year composite end point of mortality, reinfarction, refractory ischemia, and hospital readmission because of heart failure; resource use at 30 days and 1 year; and the incidence of inhospital stroke and bleeding complications in the 2 groups.

Results

Seventy-four patients have been randomized (as of March 10, 2004); results are expected in June 2005.

Conclusion

This study will establish whether angioplasty must be started as soon as possible in all patients who receive combined pharmacologic reperfusion with the glycoprotein IIb/IIIa inhibitor abciximab and half-dose thrombolysis or whether it can be postponed or skipped in patients with signs of successful reperfusion, with obvious organizational advantages.     

Eptifibatide and low-dose tissue plasminogen activator in acute myocardial infarction: the integrilin and low-dose thrombolysis in acute myocardial infarction (INTRO AMI) trial

OBJECTIVES: This study was designed to test the hypothesis that eptifibatide and reduced-dose tissue plasminogen activator (t-PA) will enhance infarct artery patency at 60 min in patients with acute myocardial infarction (AMI). BACKGROUND: Combination fibrin and platelet lysis improves epicardial and myocardial reperfusion in AMI. METHODS: Patients were enrolled in a dose finding (Phase A, n = 344) followed by a dose confirmation (Phase B, n = 305) protocol. All patients received aspirin and weight-adjusted heparin and underwent angiography at 60 and 90 min. In Phase A, eptifibatide in a single or double bolus (30 min apart) of 180, 180/90 or 180/180 microg/kg followed by an infusion of 1.33 or 2.0 microg/kg per min was sequentially added to 25 or 50 mg of t-PA. In Phase B, patients were randomized to: 1) double-bolus eptifibatide 180/90 (30 min apart) and 1.33 microg/kg per min infusion with 50 mg t-PA (Group I); 2) 180/90 (10 min apart) and 2.0 g/kg per min with 50 mg t-PA (Group II); or 3) full-dose, weight-adjusted t-PA (Group III). RESULTS: In Phase A, the best rate of Thrombolysis In Myocardial Infarction (TIMI) flow grade 3 was achieved using 180/90/1.33 microg/kg per min eptifibatide with 50 mg t-PA: 65% and 78% at 60 and 90 min, respectively. In Phase B, the incidence of TIMI flow grade 3 at 60 min was 42%, 56% and 40%, for Groups I through III, respectively (p = 0.04, Group II vs. Group III). The median corrected TIMI frame count was 38, 33 and 50, respectively (p = 0.02). TIMI major bleeding was reported in 8%, 11% and 6%, respectively; intracranial hemorrhage occurred in 1%, 3% and 2% of patients (p > 0.5 for both). The incidences of death (4%, 5% and 7%), reinfarction or revascularization at 30 days were similar among the three treatment groups. CONCLUSIONS: In comparison with standard t-PA regimen, double-bolus eptifibatide (10 min apart) with a 48-h infusion and half-dose t-PA (Group II) is associated with improved quality and speed of reperfusion. The safety profile of this therapy is similar to that of other combination regimens.     

Time delay in the treatment of acute myocardial infarction (AMI): a comparison of primary percutaneous transluminal coronary angioplasty (PTCA) with thrombolysis

Abstract Background: If primary percutaneous transluminal coronary angioplasty (PTCA) cannot be performed within times comparable to thrombolysis, the possible advantages of that management may be offset by the logistic difficulties associated with its delivery.
Aim: To measure and compare the time delay involved in administration of thrombolysis and primary PTCA over a one year period and examine causes for delay greater than 60 minutes.
Method: Prospective data collection on all patients treated with primary PTCA or thrombolysis. A quality improvement process was applied.
Results: Eighty-five patients were treated with thrombolysis with a delay of 39±8 (SD) minutes, 12 patients being treated more than 60 minutes after presentation. Primary PTCA was used in 79 patients with a delay of 48±12 (SD) minutes, 21 patients being treated after more than 60 minutes. Time delays in the two management groups were significantly different (p=0.03) but that in primary PTCA during routine hours was not significantly different from that in thrombolysis treated patients (p=0.07). Causes for revascularisation delay greater than 60 minutes from presentation are discussed.
Conclusions: With appropriate facilities and organisation, patients with acute myocardial infarction presenting within normal working hours can be treated with primary PTCA without compromising their care due to time delay. Many patients managed with primary revascularisation by thrombolysis or primary PTCA with a delay of more than 60 minutes have identifiable clinically appropriate delays.     

Interventional management of acute myocardial infarction (AMI)

The best way to limit infarct size and improve survival in patients with early heart attacks is to restore as quickly as possible patency in the infarct-related artery and blood flow to the threatened myocardium. The value of thrombolytic therapy and aspirin has been shown in large clinical trials. A regimen of accelerated recombinant tissue plasminogen activator is more effective than those using streptokinase. In older patients, there is a greater risk of haemorrhagic stroke; nevertheless, thrombolytic treatment saves more lives because the mortality of myocardial infarction (MI) is higher.
Thrombolytic therapy fails to restore blood flow sufficiently rapidly or completely in nearly one-fifth of patients. Its efficacy, therefore, has been compared with immediate or direct angioplasty (PTCA). If it can be done promptly enough, PTCA is superior in preventing recurrent ischaemia and the combined outcome of death or non-fatal reinfarction, and is associated with a lesser risk of intracranial haemorrhage. It may also be cheaper because patients spend less time in hospital and fewer of them require late revascularisation. PTCA should be considered for patients with cardiogenic shock or for those in whom there is a contraindication to thrombolytic therapy.
The benefits of prompt treatment have been reduced by excessive delay in reaching hospital and door-to-needle time.
After fibrinolysis, coronary angiography and PTCA may be reserved for those with spontaneous angina or exercise-induced ischaemia.     

Efficacy of intracoronary thrombolysis versus percutaneous transluminal coronary angioplasty for treating acute myocardial infarction]

The usefulness of percutaneous transluminal coronary angioplasty (PTCA) in patients with evolving myocardial infarction remains controversial. We retrospectively assessed the efficacy of PTCA on myocardial salvage in acute myocardial infarction in comparison with the efficacy of intracoronary thrombolysis (ICT). Sixty-two patients with initial anteroseptal myocardial infarction who had been treated within 6 hrs after the onset of chest pain were categorized into 4 groups: 1) spontaneous recanalization: n = 14, 2) successful PTCA: n = 25 (this group was further subdivided into 2 groups: direct PTCA group, primary PTCA without prior ICT: n = 19; and rescue PTCA group, PTCA after unsuccessful ICT: n = 6), 3) successful ICT group (n = 12), and 4) unsuccessful recanalization group (n = 11). Left ventricular function in the chronic phase was assessed by contrast ventriculography using the global ejection fraction (EF) and regional wall motion (RWM) was assessed by the centerline method. Patients with recanalization had a significantly higher EF than did those without (62 +/- 12 vs 50 +/- 13%, p < 0.01). The mean EFs for groups with successful reperfusion were as follows: 65 +/- 8% for the spontaneous recanalization group, 61 +/- 14% for PTCA group (64 +/- 13% for direct PTCA group, 51 +/- 13% for rescue PTCA group) and 60 +/- 12% for the ICT group. The EFs for the spontaneous recanalization group and the direct PTCA group were significantly greater than that for the rescue PTCA group. The time to reperfusion and the thrombolysis in myocardial infarction (TIMI) flow grade before reperfusion did not affect the preservation of global left ventricular function. RWM of the infarcted area in patients with recanalization were less hypokinetic than that in patients without (p < 0.01). The mean RWM (SD/chord) in the successfully reperfused groups were -2.3 +/- 1.2 for the spontaneous recanalization group, -2.6 +/- 1.2 for the PTCA group (-2.3 +/- 1.1 for the direct PTCA group, -3.3 +/- 1.0 for rescue PTCA group) and -3.0 +/- 0.5 for the ICT group. Hypokinesis of the infarcted area was more severe in the rescue PTCA group than in the spontaneous recanalization group and the direct PTCA group (multiple comparison test p < 0.01, respectively), and hypokinesis was more severe in the ICT group than in the direct PTCA group (Student's t-test, p < 0.05).(ABSTRACT TRUNCATED AT 400 WORDS)     

Primary angioplasty and thrombolysis are both reasonable options in acute myocardial infarction

Primary angioplasty is increasingly being advocated as the preferred approach for treating acute ST-segment elevation myocardial infarction regardless of whether interinstitutional transfer is required. This review critically analyzes the evidence comparing primary angioplasty with thrombolytic therapy and concludes that reasonable health care professionals may still find considerable uncertainty about the superiority of primary angioplasty for all situations. The magnitude of benefit for primary angioplasty over thrombolysis is probably less than 1 to 2 lives saved/100 patients treated and largely depends on the choice of thrombolytic agent, time to treatment, place of treatment, and adjunctive therapy. There is little evidence that systematically transferring patients for primary angioplasty in routine practice will provide any health benefits over thrombolysis. Consequently, it may be most useful to view these treatments as complementary rather than competitive. Thrombolysis remains a clinically and economically attractive option for the treatment of acute myocardial infarction that does not require the radical restructuring of our health care systems.