| Popis: |
Objectives: The aims of the thesis were to assess coronary artery remodelling and plaque load, and to determine whether this influences vascular and endothelial function in vivo in man. Methods: Coronary artery remodelled segments were categorised using intravascular ultrasound (IVUS). Plaque type was characterised directly from spectral analysis of the radiofrequency ultrasound signal. Central arterial stiffness was assessed using non-invasive measures of arterial stiffness obtained by applanation tonometry of the radial, carotid and femoral artery. Coronary artery plaque volume was determined following computerised three-dimensional reconstruction of IVUS images obtained during a motorised pullback device. Coronary vessel area, arterial stiffness and vasomotor responses were determined using IVUS and Doppler Flow measurement and endothelial fibrinolytic response by coronary sinus sampling during selective intracoronary infusions. Conclusions: Pulse wave analysis may be a useful non-invasive surrogate marker for the extent of coronary atherosclerosis. Atherosclerotic risk factors and coronary plaque load are associated with impaired vasomotor and endogenous fibrinolytic function. Though plaque type was similar in remodelled types, negative remodelling was associated with more pronounced local vascular and endothelial dysfunction. These findings collectively suggest an important local interrelationship between coronary vascular structure and function that has implications for the pathophysiology of ischaemic heart disease. |
