Persistent Link:
http://hdl.handle.net/10150/184944
Title:
Microvascular dysfunction during cardiac preservation.
Author:
Manciet, Lorraine Hanna.
Issue Date:
1989
Publisher:
The University of Arizona.
Rights:
Copyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.
Abstract:
Heart transplantation is, for certain types of cardiovascular disease, the only form of treatment resulting in patient survival. Its clinical application is, however, limited by the shortage of donor organs. This shortage is largely due to the inability to consistently preserve adequate myocardial function over prolonged ischemic periods. It is the goal of this research to provide information which may contribute to techniques for heart preservation, thus improving graft survival following preservation and transplantation. Current methods for myocardial preservation generally involve the arrest and immersion of the heart in cold cardioplegic solution, the composition of which is designed to provide for the reduced metabolic demands of the cold, arrested muscle. These methods have extended the preservation period to approximately 6 hours; however, hearts cannot be held longer than this period because, although metabolism has been slowed by hypothermia, alterations take place which compromise functional recovery upon reperfusion. A variety of perfusates and perfusion techniques have been developed to protect the myocardium from the damage thought to occur as a consequence of ischemic storage of the isolated heart. However, a consistently successful technique for long-term preservation of the heart remains undefined. A growing body of knowledge has led to the hypothesis that injury to the microcirculation may result in myocardial ischemia during preservation and decreased contractile function following preservation. To test this hypothesis, standard Langendorff techniques for the measurement of left ventricular function were combined with biochemical, histological and morphological techniques to determine: (1) whether loss of microvascular function occurs in isolated hearts hypothermically perfused with an oxygenated solution; (2) the impact of microvascular dysfunction during the preservation period on the functional recovery of hearts; and (3) which mechanisms contribute to decreased microvascular function during preservation. This experimental approach will allow for characterization of the role of the microvasculature in decreased contractility of preserved hearts and will provide information regarding the contribution of specific mechanisms to the compromised contractility of preserved hearts. Systematic evaluation of mechanisms thought to be responsible for decreased contractility of isolated hearts could contribute to improved myocardial preservation techniques that can be applied to clinical transplantation.
Type:
text; Dissertation-Reproduction (electronic)
Keywords:
Heart -- Preservation; Isolation perfusion (Physiology); Microcirculation; Perfusion (Physiology)
Degree Name:
Ph.D.
Degree Level:
doctoral
Degree Program:
Physiology; Graduate College
Degree Grantor:
University of Arizona

Full metadata record

DC FieldValue Language
dc.language.isoenen_US
dc.titleMicrovascular dysfunction during cardiac preservation.en_US
dc.creatorManciet, Lorraine Hanna.en_US
dc.contributor.authorManciet, Lorraine Hanna.en_US
dc.date.issued1989en_US
dc.publisherThe University of Arizona.en_US
dc.rightsCopyright © is held by the author. Digital access to this material is made possible by the University Libraries, University of Arizona. Further transmission, reproduction or presentation (such as public display or performance) of protected items is prohibited except with permission of the author.en_US
dc.description.abstractHeart transplantation is, for certain types of cardiovascular disease, the only form of treatment resulting in patient survival. Its clinical application is, however, limited by the shortage of donor organs. This shortage is largely due to the inability to consistently preserve adequate myocardial function over prolonged ischemic periods. It is the goal of this research to provide information which may contribute to techniques for heart preservation, thus improving graft survival following preservation and transplantation. Current methods for myocardial preservation generally involve the arrest and immersion of the heart in cold cardioplegic solution, the composition of which is designed to provide for the reduced metabolic demands of the cold, arrested muscle. These methods have extended the preservation period to approximately 6 hours; however, hearts cannot be held longer than this period because, although metabolism has been slowed by hypothermia, alterations take place which compromise functional recovery upon reperfusion. A variety of perfusates and perfusion techniques have been developed to protect the myocardium from the damage thought to occur as a consequence of ischemic storage of the isolated heart. However, a consistently successful technique for long-term preservation of the heart remains undefined. A growing body of knowledge has led to the hypothesis that injury to the microcirculation may result in myocardial ischemia during preservation and decreased contractile function following preservation. To test this hypothesis, standard Langendorff techniques for the measurement of left ventricular function were combined with biochemical, histological and morphological techniques to determine: (1) whether loss of microvascular function occurs in isolated hearts hypothermically perfused with an oxygenated solution; (2) the impact of microvascular dysfunction during the preservation period on the functional recovery of hearts; and (3) which mechanisms contribute to decreased microvascular function during preservation. This experimental approach will allow for characterization of the role of the microvasculature in decreased contractility of preserved hearts and will provide information regarding the contribution of specific mechanisms to the compromised contractility of preserved hearts. Systematic evaluation of mechanisms thought to be responsible for decreased contractility of isolated hearts could contribute to improved myocardial preservation techniques that can be applied to clinical transplantation.en_US
dc.typetexten_US
dc.typeDissertation-Reproduction (electronic)en_US
dc.subjectHeart -- Preservationen_US
dc.subjectIsolation perfusion (Physiology)en_US
dc.subjectMicrocirculationen_US
dc.subjectPerfusion (Physiology)en_US
thesis.degree.namePh.D.en_US
thesis.degree.leveldoctoralen_US
thesis.degree.disciplinePhysiologyen_US
thesis.degree.disciplineGraduate Collegeen_US
thesis.degree.grantorUniversity of Arizonaen_US
dc.identifier.proquest9014673en_US
dc.identifier.oclc703617317en_US
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