Double-blind randomized trial of alteplase versus placebo in patients with chest pain at rest

A time-to-treatment analysis in the medicine versus angiography in thrombolytic exclusion (MATE) trial

Patients with acute coronary syndromes who are considered ineligible for thrombolytic therapy are at high risk of recurrent ischemia and death. This trial randomized 201 patients to triage angiography in the first 24 hours of hospital admission versus conventional medical care. Of the 165 patients who underwent angiography that was either protocol-driven or on the basis of physician preference, those who underwent angiography within 6 hours of symptom onset had a reduction in early and late adverse events. The rates of in-hospital recurrent ischemia were 15.4%, 15.4%, 17.5%, 32.4%, and 38.5%, respectively (P = 0.01 for trend), and rates of cumulative recurrent myocardial infarction or death were 0%, 12.8%, 10.0%, 11.8%, and 7.7%, respectively (P = 0.48 for trend) for patients who underwent angiography at 0-6, 6-12, 12-24, 24-48, and over 48 hours, respectively from symptom onset. Future trials of invasive versus conservative therapy should focus on performing angiography within 6 hours of symptom onset.

A prospective randomized trial of triage angiography in acute coronary syndromes ineligible for thrombolytic therapy. Results of the medicine versus angiography in thrombolytic exclusion (MATE) trial

OBJECTIVES

The purpose of this study was to determine if early triage angiography with revascularization, if indicated, favorably affects clinical outcomes in patients with suspected acute myocardial infarction who are ineligible for thrombolysis.

BACKGROUND

The majority of patients with acute myocardial infarction and other acute coronary syndromes are considered ineligible for thrombolysis and therefore are not afforded the opportunity for early reperfusion.

METHODS

This multicenter, prospective, randomized trial evaluated in a controlled fashion the outcomes following triage angiography in acute coronary syndromes ineligible for thrombolytic therapy. Eligible patients (n=201) with <24 h of symptoms were randomized to early triage angiography and subsequent therapies based on the angiogram versus conventional medical therapy consisting of aspirin, intravenous heparin, nitroglycerin, beta-blockers, and analgesics.

RESULTS

In the triage angiography group, 109 patients underwent early angiography and 64 (58%) received revascularization, whereas in the conservative group, 54 (60%) subsequently underwent nonprotocol angiography in response to recurrent ischemia and 33 (37%) received revascularization (p=0.004). The mean time to revascularization was 27+/-32 versus 88+/-98 h (p=0.0001) and the primary endpoint of recurrent ischemic events or death occurred in 14 (13%) versus 31 (34%) of the triage angiography and conservative groups, respectively (45% risk reduction, 95% CI 27-59%, p=0.0002). There were no differences between the groups with respect to initial hospital costs or length of stay. Long-term follow-up at a median of 21 months revealed no significant differences in the endpoints of late revascularization, recurrent myocardial infarction, or all-cause mortality.

CONCLUSIONS

Early triage angiography in patients with acute coronary syndromes who are not eligible for thrombolytics reduced the composite of recurrent ischemic events or death and shortened the time to definitive revascularization during the index hospitalization. Despite more frequent early revascularization after triage angiography, we found no long-term benefit in cardiac outcomes compared with conservative medical therapy with revascularization prompted by recurrent ischemia.

Effects of streptokinase in patients presenting within 6 hours of prolonged chest pain with ST segment depression

BACKGROUND

The effects of streptokinase on the occurrence of a combined clinical outcome in patients presenting with recent chest pain and ST depression were investigated in view of the role of thrombus in the pathogenesis of acute ischaemic syndromes.

METHODS

112 patients aged < or = 75 years presenting within 6 h of the last episode of ischaemic chest pain of least 20 min duration with > or = 1 mm ST depression were randomised in a double blind manner to receive either streptokinase 1.5 million units over 30 min (n = 57) or placebo (n = 55). The primary end point was the combination of death, frequency of myocardial infarction (defined as peak creatine kinase > 600 U/ml), need for angiography because of uncontrollable ischaemia, and an exercise test within 35 days showing > or = 1 mm ST depression at < or = 6 min. The secondary end points were safety, frequency of chest pain, readmission with myocardial infarction or unstable angina, or need for revascularisation between 35 days and 1 year. The severity of ST depression on presentation was analysed with respect to clinical outcome.

RESULTS

The frequency of the combined hierarchical end point of death, myocardial infarction, early angiography, and a positive exercise test was 82% (47 of 57 patients) with streptokinase and 75% (41 of 55 patients) with placebo. There were four deaths, two in each group. 27 patients (47%) receiving streptokinase and 22 (40%) receiving placebo developed myocardial infarction. 11 patients (eight streptokinase and three placebo) required coronary arteriography and subsequent revascularisation because of angina uncontrolled by medical treatment. 44 patients (22 in each group) had a positive exercise test. There were three further cardiac deaths (one streptokinase, two placebo), and three noncardiac deaths within 1 year. A conservative approach to intervention was adopted and over a period of 1 year 29 patients (26%) (13 streptokinase and 16 placebo) underwent revascularisation procedures. Three patients (two streptokinase and one placebo) required transfusion. ST depression > or = 3 mm had 90% specificity but only 60% positive predictive value for myocardial infarction at presentation (P = 0.008, stepwise logistic regression). ST depression > or = 2 mm was predictive of death, late development of myocardial infarction, or a need for angiography (P = 0.02).

CONCLUSION

Patients presenting with ischaemic chest pain and ST depression frequently develop myocardial infarction. Severe ST depression is predictive of an adverse outcome. The 35 day (3.6% cardiac and total) and 1 year mortality (8.9% total, 6.3% cardiac) are low with conservative management and expeditious revascularisation. Streptokinase treatment within 6 h of the last episode of pain does not seem to be beneficial.