Kim M, et al. - Researchers investigated if the apoptotic biomarker caspase-3 p17 was elevated in the coronary sinus (CS) during cardioplegia and whether any elevations were reflected in the peripheral venous (PV) blood. In CS and PV, cardiac troponin I (cTnI) and caspase-1 p20 levels were also measured. They collected blood samples before and at the end of cardioplegia in PV and CS, as well as measured the levels of p20, p17, and cTnI. They observed that before and at the end of cardioplegia, there was a remarkable rise in the levels of cTnI, p20, and p17 PV when compared to the control population. Post-cardioplegia increases in PV levels of all 3 markers were evident. At both time points, higher CS levels vs PV levels were observed for all 3 markers. Based on the findings, cardiac apoptosis and inflammation occurred during cardioplegia, in addition to necrosis. The contribution of heart-derived markers to the peripheral levels was demonstrated. To gauge cardiac preservation, measurement of PV biomarker concentrations can be used.