Quantitating the biological variation of cardiac troponin in health and disease states to optimise the diagnosis of myocardial injury

The diagnosis of acute myocardial injury requires a rise and/or fall of cardiac troponin (cTn), with at least one concentration above the 99th percentile. This thesis sought to quantify the biological variation and 99th percentile of cTn in defined populations to aid diagnosis using a high-sensitivity assay. The biological variation of cTnI was similar between end-stage renal failure and cardiomyopathy patients, although both were proportionately lower than healthy individuals with low cTnI. The 99th percentile of cTnI for elderly men was similar to healthy younger adults. Adding cTnI to the Framingham risk calculator improved cardiovascular risk prognostication in elderly men.