Fibrinolytic therapy: is it a treatment of the past?

Abstract

Fibrinolytic therapy has been an important means of establishing reperfusion for decades. However, limitations to the use of thrombolytic therapy include perceived or definite contraindications, intracranial bleeding, inability to establish Thrombosis In Myocardial Infarction (TIMI-3) flow in many patients, and high rates of recurrent ischemia and reocclusion. Accordingly, primary percutaneous coronary intervention (PCI) has emerged as the preferred reperfusion strategy. Nearly all acute myocardial infarction (AMI) patients are eligible for emergency catheterization. Knowledge of the coronary anatomy allows immediate triage to surgery, medical therapy, or primary PCI, when appropriate, and results in earlier hospital discharge compared to thrombolytic therapy.1 Primary PCI establishes TIMI-3 flow in >90% of patients and is associated with reduced rates of recurrent ischemia and reocclusion. With the addition of stenting, reocclusion has been further reduced to 5% at routine 6-month angiography.2,3 Small studies have suggested that pharmacological adjuncts to PCI such as abciximab may improve myocardial perfusion and limit infarct size4,5 without the risk of bleeding observed with thrombolytic therapy.6 Finally, new technologies such as coronary thrombectomy, distal projection, and systemic cooling are easily applied in the catheterization laboratory and may further improve myocardial perfusion and infarct size. Although primary PCI has been in use for more than 25 years, the first trials randomizing PCI to intravenous thrombolytics therapy were not published until 1993.7 A meta-analysis of the first 10 randomized trials demonstrated a reduction in death, reinfarction, and stroke with primary PCI in all subgroups, but the greatest absolute benefit was observed in high-risk patients.8 On the basis of these early results, many experienced interventionalists were no longer willing to randomize patients to thrombolytic therapy. Therefore, the next decade of research was focused on perfecting the primary PCI technique, with studies randomizing patients to intraaortic balloon pumps, stents, glycoprotein …