[The basic research on the high-sensitive troponin I assay, and the application to evaluation of chronic heart failure].

The mortality among patients with heart diseases increases steadily in an aging society like Japan. Among those, the patients with chronic heart failure (CHF) are thought to be increasing rapidly although the official report is missing. It is well-known that BNP or NT-proBNP is useful for a clinical diagnosis of CHF, but a role of the cardiac troponin (cTn) attracts attention as a novel biomarker of their prognosis. However, because the level of cTn in patients with CHF is far lower than that in cases of acute coronary syndrome (ACS), development of the high-sensitive method with precision is desired. In the present study, a new sensitive assay system with an analyzer, ARCHITECT STAT (cTnI hs-ARCH) was basically studied and found more sensitive than other conventional 2 sensitive methods. The performance of cTnI hs-ARCH was evaluated in patients with CHF by comparing it to findings with other 2 methods. When CHF patients are allocated into categories of NYHA classification according to their subjective symptoms, cTnI hs-ARCH was superior to other methods in discriminating subgroups. In addition, multivariable analysis disclosed that cTnI hs-ARCH is influenced by the level of renal function at the minimum among the 3 methods. Therefore, cTnI hs-ARCH may be a useful method for evaluation of prognosis in patients with CHF who often have impaired renal function.