Effectiveness of highly sensitive troponin T assay for early diagnosis of acute myocardial infarction (AMI) [Efficacia della misura della troponina T con metodo ad alta sensibilità nella diagnosi precoce di infarto acuto del miocardio]

The interpretation of cardiac troponin results has become challenging because of the availability of highly sensitive troponin assays able to detect even small cardiac damage. To investigate whether the highly sensitive cardiac troponin T assay (hs-cTnT) improves early AMI detection, a comparative evaluation between hs-cTnT and the 4th generation assay (4th-cTnT) was performed. Patients who presented to the Emergency Department from June to September 2011 with chest pain were recruited. Blood samples were taken at admission (T0), 1 (T1), 3, 6 and 12 h after presentation and were analysed by 4th-cTnT and hs-cTnT using Modular SWA E170 analyzer (Roche Diagnostics). For this study, only samples at T0 and T1 were evaluated. Of the 386 patients recruited, 32 (8.3%) had AMI. The sensitivity of hs-cTnT at T0 was 72% vs. 50% of 4th-cTnT. In T1 samples the sensitivity of hs-cTnT (97%) was slightly higher than 4th-cTnT (78%) (P=0.06). Our preliminary results showed that hs-cTnT can detect AMI 1 h after the hospital arrival in the majority of patients. Ongoing studies will define best algorithms for the effective use of hs-cTnT results in clinical practice. Rule-out and rule-in algorithms will have to be fine tuned to exploit cost-savings associated with this early diagnostic accuracy.