Impact of Epicardial plaque composition and geometry on coronary hemodynamics and flow (iEquate)

Dr Ekmejian has been investigating the relationship between plaque morphology, plaque geometry, and invasive coronary hemodynamics. The study includes patients being investigated for coronary disease, who were identified to have moderate (50-75%) narrowing of the arteries. By assessing their hemodynamics using a coronary pressure wire and an OCT (imaging technique) assessment of the plaque, it was possible to establish potential relationships between plaque morphology and geometry (i.e. size and shape of the plaque deposits), and invasive coronary dynamics.

Invasive coronary physiology has been a guideline based tool used by interventional cardiologists to determine whether a stent may improve symptoms. Although these tools are extremely useful, there are several factors which may interfere with interpretation of these results, and clinicians should be aware of these factors. Our research has shown that micro-vascular dysfunction, which affects the small vessels in the heart that we cannot see, may impact the validity of these tests.

Our research also indicates that calcific plaque may impact the reproducibility of results using different pressure wire approaches. However this may also be a factor of the complexity of the plaque geometry, and more detailed research using 3D modelling and computational fluid dynamics is being applied to answer this this.