The troponin assay is the "new kid on the block." cTnI is currently the most sensitive, specific marker for cardiac damage and will replace the other less specific cardiac markers. This is a result of continued search for measures that provide the earliest diagnosis, which in turn ensures the greatest positive influence on morbidity and mortality in acute MI. Is the cTnI assay the ultimate marker for cardiac injury? It is doubtful. Only time will tell.