This and another article in a recent edition of JAMA illustrates the significance of the new, now commonly used, high sensitivity troponin assays. With the old assay, one thought of troponin as essentially being present or not and when present, usually indicative of myocardial damage. These new assays have confirmed that troponin is and has always present in the circulating blood stream and that levels consistent with myocardial necrosis are now much higher. Does this mean that at any time there is always a 'turn over' of myocytes? These newly available assays are also good news for researchers of cardiac ischaemia re-perfusion and in the case of cardiac surgery for those who are trying to develop the 'perfect' cardioplegic solution. One is now able to detect smaller levels of myocardial damage and as confidence intervals for these assays are likely to be narrower, required number of individuals to show a significant difference will be smaller.