Značaj protekcije miokarda etapnom reperfuzijom u toku operativnog lečenja urođenih srčanih mana

Abstract

Studija ima za cilj da pokaže efekte etapne reperfuzije toplom krvnom kardioplegičnom reperfuzijom (hot shot postkondicioniranje) u odnosu na do sada korišćeni vid kardioprotekcije (hot shot). Metod: Ispitanici su randomizirano razvrstani u dve grupe u zavisnosti da li su primili kontinuiranu krvnu kardioplegičnu reperfuziju (HS) ili krvnu kardioplegičnu reperfuziju sa algoritmom za postkondicioniranje (PostK). Procenjivana je brzina funkcionalnog i metaboličkog oporavka miokarda, intenzitet ishemijsko-reperfuzionog oštećenja miokarda i postoperativni klinički i ehokardiografski rezultati. Rezultati: Sedamdesetjedan ispitanik je randomizirano podeljen u dve grupe: HS grupa ( n=34) i PostK grupa (n=37). Dve grupe se nisu razlikovale u odnosu na demografske karakteristike, tipove mana i operativne varijable. Tip reperfuzije nije uticao na mortalitet, morbiditet i rane kliničke rezultate. Nije bilo razlike između grupa u odnosu na dužinu trajanja mehaničke ventilacije i vremena u jedinici intenzivnog lečenja. Izuzev nižih ukupnih prosečnih vrednosti serumskog laktata (p=0,02) u PostK grupi, nije registrovana značajna razlika u drugim ispitivanim postoperativnim hemodinamskim varijablama, kao i ehokardiografskim parametrima funkcije leve komore. Porast vrednosti cTnT nije zavisio od primenjene reperfuzione tehnike, ali je zavisio od dužine ishemije, sa postojanjem snažne pozitivne korelacije (p<0.001). Registrovana je značajno smanjena miokardna sekvestracija leukocita u PostK grupi (p=0,005). Nije ustanovljeno postojanje među-grupne razlike u vrednostima trans-kardijalnih vrednosti serumskih laktata, Ph krvi, glukoze i sadržaja kiseonika. Zaključak: Postkondicioniranje u formi etapne reperfuzije toplom krvnom kardioplegijom nema značajan pozitivan efekat na rane kliničke rezultate, brzinu i stepen metaboličkog i funkcionalnog oporavka miokarda, kao i stepen ishemijskog oštećenja. Etapna reperfuzija dovodi do smanjene miokardne sekvestracije leukocita što potencijalno može da umanji neutrofilima indukovano oštećenje vaskularnog endotela i miocita.

This study investigates the effects of postconditioning in the form of stage cardioplegic warm blood reperfusion on functional and metabolic miocardial recovery as well as early clinical results in patients undergoing congenital cardiac lesions repair. Methods: Patients were randomly assigned to receive either continuous or intermitent warm blood hot shot. Early clinical results were assessed. Transcardiac difference in serum lactate, glucose, Ph and oxygen content were measured during the early reperfusion phase. Postoperative changes in the cardiac index, serum lactate levels, central venous saturation, cardiac Troponin T release were assessed during the first 24 hours following ishaemia. Results: Patients were randomly devided into two groups: HS group (n=34) and PostK group (n=37). Two groups were similar in terms of patients’ caracteristics, lesions distribution and operative variables. There was no difference in mortality and postoperative complications rates between groups. There were no difference in inotropic requirements, duration of ventilation time and intensive care unit stay. The postoperative changes in central venous saturation, cardiac index, Troponin T release and left ventricle function assessed by transtoracic echocardiography were similar between two groups. However, there was significant difference in the level of serum lactate (p=0.02) in favour of the PostK patients. An increase in the cTnT level was associated with prolonged ischemic time (p<0.001). Although, there was significantly lower WBC myocardial sequestration (p=0.005) in PostK group, myocardial release of lactate and acids, glucose intake and oxygen consumption were similar between two groups. Conclusion: Postconditioning using intermitent cardioplegic warm blood reperfusion does not show significant adventage comparing with continuos hot shot in terms of clinical outcome, functional recovery and the degree of ischaemic injury in children undergoing congenital heart lesions repair. Stage reperfusion decreases myocardial WBC sequestration which might atenuate neutrophiles-related vascular endothelium and myocytes injury.