Myocardial Protection by Retrograde Application of HTK Solution Compare with Cold Blood Cardioplegic Solution during Heart Valve Surgery

Objective: Cardioplegic solution is one important principle for adequate myocardial protection in cardiac surgery. Bretschneider’s histidine-tryptophan-ketoglutarate (HTK) solution is an intracellular solution while blood cardioplegia solution is an extracellular solution. Both have been used to preserve the myocardium. The present study compared between the two cardioplegic solutions for incidence of ventricular fibrillation after aortic clamp removal in double valve replacement (DVR) and tricuspid annuloplasty (TVA) to assess the effectiveness for myocardial protection. Materials and Methods: A retrospective study was conducted among patients who underwent DVR with TVA operations between January 1, 2013 and June 30, 2017 and divided in two groups at Queen Sirikit Heart Center of the Northeast. The medical records were searched for detailed demographics, preoperative status, operative technique, and post-operative hospital course. Results: Thirty-six patients were included in the present study, 18 patients received HTK solution, the others received blood cardioplegia. The demographic data presented no statistical difference between the two groups. Incidence of ventricular fibrillation after aortic clamp removal occurred in 10 patients (55.6%) in the HTK group, which was more than the cold blood group [five patients (27.78%)]. Cardiopulmonary bypass (CPB) and aortic cross clamp time in the cold blood group was significantly longer than in the HTK group (p<0.001). The peak of Trop-T and CK-MB within six hours after surgery tended to be downward after 24 hours and was not related to perioperative myocardial ischemia in the HTK group. No statistically difference was observed in postoperative outcome, ICU stay, or hospital stay. Conclusion: The use of HTK solution has no significant different outcome compared to conventional cold blood cardioplegia via retrograde route in DVR with TVA operation. There was no significantly different incidence of ventricular fibrillation and there was no evidence of postoperative myocardial infarction. CPB and aortic cross clamp time in the HTK group were shorter than in the cold blood cardioplegia significantly. Keywords: Cardioplegia, HTK, Custodiol, Ventricular fibrillation