Use this URL to cite or link to this record in EThOS: http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.504902
Title: Coronary haemodynamics in hypertension and left ventricular hypertrophy
Author: Davies, Justin Edgar Rees
Awarding Body: Imperial College London (University of London)
Current Institution: Imperial College London
Date of Award: 2011
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Abstract:
The coronary blood flow waveform is unique, being determined by simultaneous changes in pressure originating at either end of the coronary artery. However, by measuring the coronary pressure waveform alone, it is not possible to separate the pressure contributions originating from the coronary microcirculation from those originating in the aorta. In this thesis wave intensity analysis was applied to unobstructed human coronary arteries to separate the contributions originating in the coronary microcirculation from those originating in the aorta, in subjects with and without left ventricular hypertrophy. I found that coronary blood flow is predominantly regulated by changes in microcirculatory-originating pressure, and not be aortic-originating pressure as is the case in other vascular beds. I identified six waves which were responsible for directing these changes in pressure. Coronary blood flow peaks during diastole due to a dominant backward-travelling 'suction' wave, generated when microcirculatory compression is relieved and pressure in the distal artery falls rapidly. This backward-travelling 'suction' wave was found to be significantly reduced in subjects with left ventricular hypertrophy. Finally, wave intensity was applied in the proximal aorta to assess the contribution of distal reflections to coronary blood flow. Wave reflections could be seen travelling back from the proximal aorta into the coronary arteries. These reflections augment coronary blood flow during systole and are more marked in older subjects.
Supervisor: Not available Sponsor: Not available
Qualification Name: Thesis (Ph.D.) Qualification Level: Doctoral
EThOS ID: uk.bl.ethos.504902  DOI: Not available
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