Management of Patients with Acute Coronary Syndrome: Should We Rely on Cardiac Markers?

Abstract

Early diagnosis and risk stratification of patients presenting to the emergency room for a suspected acute coronary syndrome is an emerging problem. In general, diagnosis is based on an ECG, clinical presentation, and elevated cardiac markers. In the past decade cardiac troponins and myoglobin have been identified as important markers for the global assessment and treatment of patients with acute coronary syndromes. Recent studies have identified patients with increased troponin I and T levels as a high risk population gaining benefit from the adjunctive treatment with glycoprotein (GP) IIb/IIIa receptor antagonists or low molecular weight heparin. Myoglobin was introduced as a sensitive marker of successful or failed reperfusion following thrombolytic therapy. These studies indicate that cardiac markers are important tools in the risk stratification of patients with acute coronary syndromes allowing adequate treatment decisions. However, certain limitations of cardiac markers have to be considered. These limitations mainly refer to the delay in time from presentation to the emergency room to the availability of the results of the blood sample. Thus, in the individual case, especially if an ECG and clinical presentation are unspecific or there is doubt concerning the success of thrombolytic therapy, early angiography remains the gold standard for diagnosis and establishment of adequate therapy. In this setting, early reperfusion by percutaneous coronary interventions will increase myocardial salvage, and therefore, should be preferred to the delayed confirmation of the diagnosis by repeated determination of cardiac markers.