Cardiac injury biomarkers in the critically ill

To be clinically relevant, a good cardiac biomarker should have four main characteristics. It should be organ-, disease- and stage-specific to be useful in diagnosis. Its release should be timely and its half-life should be long enough to make measurement possible and meaningful. Its serum or blood concentration should be proportional to disease severity; hence, can be used as a monitoring tool. Finally, their concentrations have implications on long-term outcomes. To date, only a handful of cardiac biomarkers have clinical relevance in the intensive care setting—cardiac troponins (as a marker of cardiac injury) and B-type natriuretic peptide (as a marker of cardiac stress) being probably the most useful. However, cautious interpretations of these biomarkers are needed in intensive care patients as several confounding factors can affect their concentrations.