Routine Angioplasty and Stenting After Fibrinolysis for Acute Myocardial Infarction

Overview

Background: In Canada, most patients with acute myocardial infarction (AMI) present to hospitals without cardiac catheterization facilities. Thrombolytic therapy remains the standard-of-care in these centres. However, thrombolytic therapy achieves normal coronary flow and myocardial perfusion in less than 50% of patients, and is associated with reocclusion, reinfarction, and recurrent ischemia. Primary angioplasty results in more complete reperfusion and lower rates of reocclusion, reinfarction and recurrent ischemia, but is not available in most centres. Although patients can be transferred for primary angioplasty, long transport times are associated with worse outcomes. An alternative strategy, described as facilitated angioplasty, involves administration of thrombolytic therapy at the community hospital followed by immediate transport for angioplasty. This approach achieves the benefits of primary angioplasty without delaying treatment. A well-conducted, prospective, randomized trial is needed to compare this strategy of facilitated angioplasty with standard thrombolytic therapy. Objectives: To evaluate the safety, feasibility, and efficacy of routine transfer of patients with AMI to an angioplasty centre immediately after thrombolysis for coronary angiography and percutaneous coronary intervention (PCI). Hypothesis: A strategy of routine transfer of patients with AMI to an angioplasty centre immediately after thrombolysis for coronary angiography and percutaneous intervention is associated with a significantly lower incidence of the composite of death, reinfarction, recurrent ischemia, heart failure, and shock at 30 days compared with the conventional strategy of thrombolysis with transfer reserved for failed reperfusion and/or development of shock. Research Plan: Patients with ST-elevation myocardial infarction and high-risk characteristics presenting to community hospitals without cardiac catheterization facilities will receive thrombolysis with tenecteplase and heparin (unfractionated or low molecular weight heparin) and will then be randomized to one of two strategies: facilitated PCI or standard treatment (thrombolysis with provisional rescue PCI). In the facilitated PCI group, patients will be transferred immediately to an angioplasty centre for urgent cardiac catheterization, and PCI if appropriate. In the standard treatment group, patients will only undergo urgent angiography for evidence of failed reperfusion and/or development of cardiogenic shock. The primary endpoint will be the composite of death, reinfarction, recurrent ischemia, heart failure, and shock at 30 days.

Patients with ST-elevation myocardial infarction and high-risk characteristics presenting to community hospitals without cardiac catheterization facilities will receive thrombolysis with tenecteplase and heparin (unfractionated or low molecular weight heparin) and will then be randomized to one of two strategies: facilitated percutaneous coronary intervention (PCI) or standard treatment (thrombolysis with provisional rescue PCI). In the facilitated PCI group, patients will be transferred immediately to an angioplasty centre for urgent cardiac catheterization, and PCI if appropriate within 6 hours of thrombolysis. In the standard treatment group, patients will only undergo urgent angiography for evidence of failed reperfusion and/or development of cardiogenic shock.