New insights from the MESA study: increased high-sensitivity troponins as a cardiovascular risk factor.

The most recent high-sensitivity assays for troponins I and T (hs-TnI and hs-TnT) have made it possible to detect blood concentrations up to 10 times lower than previous assays, making troponins detectable even in asymptomatic subjects without manifest cardiovascular disease. For this reason, hs-Tn, initially introduced as markers of myocardial damage in an acute setting, have also become possible markers of subclinical myocardial damage in baseline conditions. In fact, recent evidence suggests that hs-TnT and hs-TnI predict the risk of future cardiovascular events also in the context of primary prevention, and offer incremental information when added to current risk stratification models. The different association highlighted with different outcome measures, such as coronary heart disease, atherosclerotic cardiovascular disease, heart failure, and death from all causes, seems to indicate that the risk observed in asymptomatic subjects with high levels of hs-Tn is an expression of subclinical damage secondary to multiple pathophysiological mechanisms, and not only to atherothrombosis. However, the ability of hs-TnT and hs-TnI (until now used interchangeably), to provide differential predictive information, and not redundant with respect to more traditional factors, remains to be definitively clarified, both for the purpose of predicting specific outcomes and for the implementation of specific preventive strategies. To date, evidences available allow us to hypothesize their role more as markers than as risk factors.