Risk stratification and therapeutic decision making in patients with acutecoronary syndromes - the role of cardiac troponin T

Patients with chest pain represent an inhomogeneous group with greatly vary ing severity of coronary artery disease and cardiac risk. The proper select ion of different treatment strategies in these patients requires reliable r isk assessment. Patients with definitive myocardial infarction: in patients with ST-segment elevation on EGG, a positive troponin T (cTnT) on admission identifies a g roup of patients having a threefold higher mortality rate than patients wit h a negative cTnT test. The differences in risk based on cTnT are found for patients treated with thrombolytic: as well as mechanical recanalization t herapy. These differences in mortality based on admission cTnT may be expla ined by more severe coronary artery disease, worse left ventricular functio n, and less efficient microvascular reperfusion in the cTnT-positive patien ts. Patients with rest angina: in patients with angina at rest, a positive cTnT value on admission identifies a subgroup having a threefold higher cardiac event rate than cTnT-negative patients. The cTnT-positive patients seem to benefit from treatment with low molecular weight heparin and fibrinogen re ceptor antagonists, while cTnT-negative patients do not. The differences in risk and response to therapy may be due to more severe coronary artery dis ease, more critical coronary artery stenoses, and a higher rate of intracor onary thrombus formation in the cTnT-positive versus negative patients. Low risk chest pain patients: in low risk chest pain patients, (i.e. no res t angina, no EGG-changes) cTnT-positive patients on admission have a twofol d higher cardiac event rate than cTnT-negative patients. The proper treatme nt strategy for the low risk cTnT-positive patients remains to be determine d. Troponin T versus troponin I: many of the findings on cTnT also relate to t roponin I. However, there is a high interassay variability of troponin I as says, which has to be taken into consideration.