Sensitive Cardiac Troponin Assays: Myth and Magic or a Practical Way Forward?

Acute coronary syndrome (STEMI, NSTEMI and unstable angina pectoris) and risk factors, similarities and differences

Introduction: Acute coronary syndrome (ACS) is one of the m ost common and most dramatic manifestations of ischaemic h eart disease and distinguishing of ACS from non-cardiac chest pain represents a diagnostic challenge. Objective: Determine the frequency of ACS types: NSTEMI, STEMI and unstable angina pectoris (UAP) and examine the frequency and significance of risk factors and cardiospecific enzymes in patients with ACS. Methods: The analysis included patients who were referred from the prehospital level of the Banja Luka Primary Healthcare Centre (Emergency Department and Family Medicine Department) and treated under the ACS diagnosis in the coronary unit of the Cardiovascular Diseases Clinic of the Banja Luka University Clinical Centre of the Republic of Srpska (UCCRS) in the first 6 months of 2011. The study included patients older than 18, with recorded information on their gender, age, smoking status, hypertension, diabetes, obesity and family burden. Values of cholesterol, triglycerides, serum potassium, creatine kinase (CK), CK-MB, cardiac tro - ponin T (cTnT) were measured. Results: The total of 192 patients were referred under the referral diagnosis of ACS and treated in the coronary unit of the CVD Clinic of the Banja Luka UCCRS. At the same time, ACS was confirmed in 178 cases. STEMI was confirmed in 86 patients (48.31 %), NSTEMI in 55 (30.90 %) and UAP in 37 (20.79 %). ACS was statistically significantly more common in men (112 men and 66 women), in particular younger men (average age for men was 62.7 and 69.2 for men and women, respectively) (U = 2.472 x 103, p < 0.001). Among the risk factors, it was found th at smoking was more often associated with STEMI (p = 0.014) and hypertension with UAP (p = 0.041). Among all param eters, all three examined cardiac biomarkers showed statistical significance (p < 0.001), namely: values at STEMI > NSTEMI > UAP. Conclusion: Half of patients with ACS did not have STEMI (which is presumably easy to diagnose). Third of patients with ACS reported atypical symptoms, which further complicates the early recognition of MI without ST elevation. Precaution is needed in women and in elderly. Determination of cTnT should be available in every examination room.

Diagnostic and Prognostic Information Provided by a High Sensitivity Assay for Cardiac Troponin T

Cardiac troponins (cTns) are the preferred biomarkers for the diagnosis of acute myocardial infarction, assessment of risk and prognosis, and for determination of antithrombotic and revascularization strategy in patients with acute coronary syndromes. The implementation of high sensitivity cTn assays into the clinical routine has increased the number of patients diagnosed with myocardial infarction. In addition, the number of patients with elevated cTn levels that cannot be explained by acute ischemic injury was increased, which is observed in patients with chronic heart disease and other nonischemic cardiac injury or in patients with impaired renal function. The new definition of myocardial infarction provides support for the interpretation of elevated cTn measured with high sensitivity cTn assays in patients with suspected acute coronary syndrome. This review will summarize clinical studies with the recently introduced high sensitivity cTnT assay (TnT hs) with reference to recent experience with high sensitivity cTn assays in general.