Coronary interventions and their impact on post myocardial infarction survival

Abstract

Rapid reestablishment of infarct vessel patency and microvascular flow provides the best opportunity for minimizing mortality in the patient post myocardial infarction (MI). Early infarct artery patency can be restored by thrombolysis, primary angioplasty, or facilitated percutaneous coronary intervention (PCI). In comparative studies, primary angioplasty offers a greater mortality benefit than thrombolysis in patients with acute MI. Short-term rates of mortality and stroke were significantly lower in patients receiving primary angioplasty compared with thrombolysis, as was the risk of nonfatal reinfarction. The timing of reperfusion therapy after symptom onset affects outcomes. Patients presenting >3 h after symptom onset are likely to benefit more from PCI than from thrombolysis. Nevertheless, PCI should be performed as soon as possible for optimal results. If PCI is to be delayed, then immediate thrombolysis is likely to be as effective as PCI. Registry data indicate that reperfusion for acute MI is currently underused, with different techniques frequently misapplied. Outcomes tend to be better at centers that perform a high volume of reperfusion procedures, partly due to shorter treatment delays. Facilitated PCI combines fibrinolytic therapy with angioplasty. It is designed to promote very early patency in those who respond to drug therapy, with very high final patency rates assured by angioplasty. Clinical trials have generally found facilitated PCI to be more efficacious than thrombolysis alone. Rescue PCI in cases of failed fibrinolysis is associated with a modest mortality benefit compared with conservative treatment. Myocardial injury following reperfusion after ischemia can limit the benefits of PCI and fibrinolysis; however, strategies for minimizing reperfusion injury have not yet shown clinical efficacy.