Coronary stenosis physiology appraisal Handle with care

Ischemic heart disease (IHD) may occur due to the presence of a coronary artery stenosis and microvascular dysfunction. In patients with coronary artery stenosis, the diagnostic goal is to assess the functional stenosis severity, i.e. the potential of the stenosis to limit myocardial perfusion, in order to select appropriate treatment. Invasive diagnostic tests provide this opportunity. These tests can be performed at resting myocardial blood flow (baseline) and during induced vasodilation of the coronary microcirculation (hyperemia). Indices derived from intracoronary measurements have been increasingly adopted in the last decade. However, the oversimplification of coronary pathophysiology underlying the derivation of these diagnostic tools may affect the choice for treatment and their prognostic power at the individual patient level.
This thesis sought to provide further insights into the invasive physiological assessment of coronary artery stenosis severity, by means of combined intracoronary pressure and velocity measurements. In particular, the effect of changes in myocardial oxygen demand, coronary hemodynamics variability and procedural aspects on current baseline and hyperemic functional indices were investigated throughout this thesis.