Routine Angioplasty and Stenting After Fibrinolysis for Acute Myocardial Infarction

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.

Inclusion criteria

• Patients >= 18 years old who present within 12 hours of symptom onset with more than 30 minutes of continuous symptoms of an acute myocardial infarction to a centre that does not perform primary PCI, with either:

• >= 2 mm ST-segment elevation in 2 or more contiguous anterior leads
• >= 1 mm ST-segment elevation in 2 or more contiguous inferior leads with at least one of the following high-risk features:

• Systolic blood pressure < 100 mm Hg
• Heart rate > 100/minute
• Killip Class II-III
• >= 2 mm ST-segment depression in anterior leads
• >= 1 mm ST-segment elevation in right-sided lead V4 (V4R), indicative of right ventricular involvement

Exclusion criteria

• Left bundle branch block
• Cardiogenic shock (Killip Class IV requiring vasopressors or inotropic support to maintain a systolic blood pressure > 90) prior to randomization
• Active bleeding or known hemorrhagic diathesis
• Availability of primary PCI with door-to-balloon time ≤ 60 minutes
• Time from thrombolysis to initiation of consent process > 30 minutes
• Use of thrombolytic agent other than tenecteplase (TNK) for index event
• Major surgery, biopsy of parenchymal organ, or significant trauma in the past 6 weeks
• Systolic blood pressure > 200 mm Hg or diastolic > 110 mm Hg after arrival to the hospital and before enrollment
• Concomitant use of oral anticoagulants (e.g. warfarin) with International Normalized Ratio (INR) of > 2
• Recent non-compressible vascular puncture
• History of central nervous system structural damage (e.g. aneurysm, neoplasm, arteriovenous malformation, stroke) at any time, or transient ischemic attack within the last year
• History of heparin-induced thrombocytopenia
• Documented allergy to aspirin
• Participation in other clinical research studies involving experimental therapies including drugs or devices within 7 days of enrollment or prior participation in this study
• Inability to cooperate with the protocol or undergo cardiac catheterization
• Other serious illness (e.g. active cancer, significant hepatic disease)
• Serum creatinine > 140 umol/L
• Percutaneous coronary intervention within one month
• Previous bypass surgery
• Pregnancy
• Use of enoxaparin (or other low molecular weight heparin) in last 12 hours in patient > 75 years of age
• Inferior ST-elevation myocardial infarction with none of the 5 high-risk features listed in the inclusion criteria