Modern challenges in acute coronary syndrome
Despite a growing evidence base, gaps in knowledge and practice leave room for improvement in the treatment of acute coronary syndrome
A few decades ago, there was still controversy about the importance of interruption of blood flow versus myocardial tissue oxygen demand in causing myocardial infarction.1,2 It is now universally accepted that coronary thrombosis at the site of an unstable atherosclerotic plaque is the usual cause of coronary occlusion3 and the cluster of conditions of unstable angina, non-ST-elevation myocardial infarction (NSTEMI) and ST-elevation myocardial infarction (STEMI) comprise the clinical complex now called acute coronary syndrome (ACS).
An important observation from the investigations at the start of the “reperfusion era” was the recognition that STEMI and NSTEMI, while both due to coronary thrombosis, had quite different presentations and natural histories.4 Important differences between the pathophysiology of STEMI and NSTEMI determine the focus of treatment. In STEMI, the complete occlusion of the coronary vessel initiates a cascade of myocardial necrosis, which can be prevented by early reperfusion with percutaneous coronary intervention or fibrinolytic therapy.5 In NSTEMI, the less complete occlusion…