Abstract 14031: Effects of Custodiol-HTK and Del Nido Solutions in a Coronary-Perfused Rabbit Ventricular Wedge Model

Abstract

Introduction: Distinct cardioplegic solutions are used in cardiac surgery for myocardial protection. Custodiol-HTK (CUS) solution consists of histidine, tryptophan, ketoglutarate and mannitol to reduce cellular edema. Del Nido (DN) is a nonglucose-based solution containing low calcium and high lidocaine concentrations, preventing intracellular Ca2+ accumulation during ischemia. Hypothesis: Using a coronary-perfused rabbit experimental model, this study compares the effects of CUS and DN on transmural electrocardiogram (ECG) and tension parameters. Methods: Twelve left ventricular (LV) wedge preparations from 12 rabbit hearts were arterially perfused with Tyrode's solution and stimulated at a cycle length of 1000 ms. Simultaneous recording of transmural ECG and tension were obtained. After exposure to normal Tyrode, the LV wedge preparation was perfused with 20 cc of CUS (n=6) or 20 cc of DN (n=6) leading to complete arrest maintained for 30 minutes. ECG and tension recordings were obtained under baseline conditions and at 5, 15, and 30 minutes after reperfusion with normal Tyrode. Differences in change from baseline ECG and tension parameters after CUS or DN were compared using a mean differences regression model. Results: Reperfusion effects of CUS and DN on ECG and tension are shown in Table 1 . After reperfusion, DN group had a significantly greater increase in QRS duration, significantly more QT shortening and more ST segment change compared to CUS group. At 5- and 15-minutes post-reperfusion, the CUS group had significantly higher tension recovery. Negative T wave were observed in 1 of 6 wedges of the CUS group and 5/6 (83.3%) wedges of the DN group. Conduction block was observed in 0/6 wedges in the CUS group and 5/6 (83.3%) wedges in the DN group. Conclusions: In a LV coronary-perfused rabbit wedge preparation, Custodiol-HTK cardioplegia led to less ischemic changes in ECG and faster tension recovery following reperfusion compared to del Nido cardioplegia.