Comparison of del Nido and Histidine‐tryptophan‐ketoglutarate cardioplegic solutions on cardiac and endothelial function

Abstract

ObjectivesThis study was designed to compare cardiac and endothelial protection of three clinically used cardioplegias del Nido (DNC), Histidine‐tryptophan‐ketoglutarate (HTK), and cold blood (BC) cardioplegia followed by HTK (BC+HTK) in ischemia/reperfusion(I/R)rat model.MethodsSixty male Wistar rats were subjected to either 120‐min global ischemia at 4°C followed by 90‐min reperfusion at 37°C or no I/R (Control) in Langendorff apparatus and were randomly allocated into five groups: Control, I/R, DNC, HTK, and BC+HTK. Hemodynamic parameters were continuously recorded. The endothelium‐dependent relaxation to acetylcholine (ACh) was measured in the left anterior descending artery thereafter in myograph. The protein expression of cardiac Troponin T (cTnT) and creatine Kinase MB (CKMB) were measured by western blotting.ResultsDuring reperfusion, HTK had higher LVSP whereas DNC had lower LVEDP, better LVDP, and best +dp/dtmax and ‐dp/dtmax than other two groups but the differences disappeared at the end of the reperfusion. HTK or BC+HTK preserves the ACh‐induced endothelium‐dependent relaxation better than DNC (Emax=48.2±8.0% in DNC vs. 75.0±8.0% in HTK, p<0.05; vs. 96.9±3.5% in BC+HTK, p<0.001). The protein level of cTnT and CKMB was downregulated in the three groups.ConclusionsDNC shows a better recovery in diastolic function, whereas HTK or BC+HTK exerts better protection in coronary endothelial function. All these three cardioplegias could ameliorate the myocardium injury at the protein level. These findings may suggest that searching for “perfect” cardioplegia is warranted.