Cardiac-specific methylation patterns of circulating DNA for identification of cardiomyocyte death

BACKGROUND: Correct detection of human cardiomyocyte death is essential for definitive diagnosis and appropriate management of cardiovascular diseases. Although current strategies have proven utility in clinical cardiology, they have some limitations. Our aim was to develop a new approach to monitor myocardial death using methylation patterns of circulating cell-free DNA (cf-DNA). METHODS: We first examined the methylation status of FAM101A in heart tissue and blood of individual donors using quantitative methylation-sensitive PCR (qMS-PCR). The concentrations and kinetics of cardiac cf-DNA in plasma from five congenital heart disease (CHD) children before and after they underwent cardiac surgery at serial time points were then investigated. RESULTS: We identified demethylated FAM101A specifically present in heart tissue. Importantly, our time course experiments demonstrated that the plasma cardiac cf-DNA level increased quickly during the early post-cardiac surgery phase, peaking at 4–6 h, decreased progressively (24 h) and returned to baseline (72 h). Moreover, cardiac cf-DNA concentrations pre- and post-operation were closely correlated with plasma troponin levels. CONCLUSIONS: We proposed a novel strategy for the correct detection of cardiomyocyte death, based on analysis of plasma cf-DNA carrying the cardiac-specific methylation signature. Our pilot study may lead to new tests for human cardiac pathologies.