Adenosine and its role in cardioplegia : experimental evaluation in the isolated rat heart and in an-vivo primate model

dc.contributor.advisorOpie, Lionel Hen_ZA
dc.contributor.advisorReichart, Ben_ZA
dc.contributor.authorBoehm, Dieter Hermannen_ZA
dc.date.accessioned2017-11-13T08:15:04Z
dc.date.available2017-11-13T08:15:04Z
dc.date.issued1997en_ZA
dc.date.updated2017-05-17T11:45:53Z
dc.description.abstractThis study was designed to investigate the role of adenosine, an endogenous cardioprotectant agent, without high potassium and as cardioplegic additive to high potassium solutions. Adenosine cardioplegia and potassium cardioplegia supplemented by adenosine (K + ADO) were investigated in terms of hemodynamic, metabolic and ultrastructural recovery in the isolated rat heart and in the in-vivo baboon model during periods of global myocardial ischemia, simulating the clinical situation during open heart surgery. The results obtained in both models show that adenosine improved postischemic hemodynamic function when used without high potassium cardioplegia. The combination of adenosine and high potassium was less effective in both models in terms of hemodynamic recovery; however, improved rhythm stability and coronary vasodilatation were still present. In addition adenosine alone was able to induce fast electromechanical arrest in the isolated rat heart. However, failure of even high concentrations of adenosine to limit ventricular fibrillation in the baboon exclude its use as cardioplegic agent on its own without additional interventions. It appears likely that adenosine without high potassium is cardioprotective via activation of A₁ receptors and opening of ATP-sensitive potassium channels, a mechanism which is probably non-functional in a high potassium environment. In view of the limited cardioprotection achieved with the combination of adenosine and high potassium further studies should aim for additional interventions to induce cardioplegia with adenosine and normokalemic solutions.en_ZA
dc.identifier.apacitationBoehm, D. H. (1997). <i>Adenosine and its role in cardioplegia : experimental evaluation in the isolated rat heart and in an-vivo primate model</i>. (Thesis). University of Cape Town ,Faculty of Health Sciences ,Division of Cardiology. Retrieved from http://hdl.handle.net/11427/26180en_ZA
dc.identifier.chicagocitationBoehm, Dieter Hermann. <i>"Adenosine and its role in cardioplegia : experimental evaluation in the isolated rat heart and in an-vivo primate model."</i> Thesis., University of Cape Town ,Faculty of Health Sciences ,Division of Cardiology, 1997. http://hdl.handle.net/11427/26180en_ZA
dc.identifier.citationBoehm, D. 1997. Adenosine and its role in cardioplegia : experimental evaluation in the isolated rat heart and in an-vivo primate model. University of Cape Town.en_ZA
dc.identifier.ris TY - Thesis / Dissertation AU - Boehm, Dieter Hermann AB - This study was designed to investigate the role of adenosine, an endogenous cardioprotectant agent, without high potassium and as cardioplegic additive to high potassium solutions. Adenosine cardioplegia and potassium cardioplegia supplemented by adenosine (K + ADO) were investigated in terms of hemodynamic, metabolic and ultrastructural recovery in the isolated rat heart and in the in-vivo baboon model during periods of global myocardial ischemia, simulating the clinical situation during open heart surgery. The results obtained in both models show that adenosine improved postischemic hemodynamic function when used without high potassium cardioplegia. The combination of adenosine and high potassium was less effective in both models in terms of hemodynamic recovery; however, improved rhythm stability and coronary vasodilatation were still present. In addition adenosine alone was able to induce fast electromechanical arrest in the isolated rat heart. However, failure of even high concentrations of adenosine to limit ventricular fibrillation in the baboon exclude its use as cardioplegic agent on its own without additional interventions. It appears likely that adenosine without high potassium is cardioprotective via activation of A₁ receptors and opening of ATP-sensitive potassium channels, a mechanism which is probably non-functional in a high potassium environment. In view of the limited cardioprotection achieved with the combination of adenosine and high potassium further studies should aim for additional interventions to induce cardioplegia with adenosine and normokalemic solutions. DA - 1997 DB - OpenUCT DP - University of Cape Town LK - https://open.uct.ac.za PB - University of Cape Town PY - 1997 T1 - Adenosine and its role in cardioplegia : experimental evaluation in the isolated rat heart and in an-vivo primate model TI - Adenosine and its role in cardioplegia : experimental evaluation in the isolated rat heart and in an-vivo primate model UR - http://hdl.handle.net/11427/26180 ER - en_ZA
dc.identifier.urihttp://hdl.handle.net/11427/26180
dc.identifier.vancouvercitationBoehm DH. Adenosine and its role in cardioplegia : experimental evaluation in the isolated rat heart and in an-vivo primate model. [Thesis]. University of Cape Town ,Faculty of Health Sciences ,Division of Cardiology, 1997 [cited yyyy month dd]. Available from: http://hdl.handle.net/11427/26180en_ZA
dc.language.isoengen_ZA
dc.publisher.departmentDivision of Cardiologyen_ZA
dc.publisher.facultyFaculty of Health Sciencesen_ZA
dc.publisher.institutionUniversity of Cape Town
dc.subject.otherCardiothoracic Surgeryen_ZA
dc.titleAdenosine and its role in cardioplegia : experimental evaluation in the isolated rat heart and in an-vivo primate modelen_ZA
dc.typeDoctoral Thesis
dc.type.qualificationlevelDoctoral
dc.type.qualificationnamePhDen_ZA
uct.type.filetype
uct.type.filetypeText
uct.type.filetypeImage
uct.type.publicationResearchen_ZA
uct.type.resourceThesisen_ZA
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