Comprehensive assessment of ischaemic heart disease with invasive pressure and flow measurements

This thesis sought to provide some novel insights on the complexity of the invasive assessment of ischaemic heart disease (IHD). Undoubtedly, focal coronary stenosis play a pivotal role in the genesis and prognosis of this entity. Furthermore, therapy guided by the functional assessment of such focal stenosis has shown to improve patient outcomes, as compared to therapy guided by their angiographic appearance alone. However, wealth of consistent data currently show how does this stenosiscentred diagnostic and therapeutical approach, relying only on the fractional flow reserve (FFR), is not perfect, since many patients with non-physiologically significant epicardial stenosis still suffer from angina and cardiovascular events, and conversely, a significant proportion of patients with FFR-significant stenosis do well at medium term. These leaves, consequently, room for further refinement. This thesis pursued to contribute to this refinement, and for these, followed a two-fold pathway. Firstly, it explored the diagnostic consequences of a simpler physiological approach, focused only on the pressure-lone assessment of focal stenosis under non-hyperaemic conditions. Secondly, it explored a more complex-yet comprehensive approach, that included, in addition to the FFR, the available indices to explore coronary microcirculation. In the following paragraphs, the salient findings of the different parts of the present thesis will be discussed in perspective.