Synopsis of Clinical Coronary Physiology

After decades of angiography-guided coronary intervention, the value of coronary physiology tools to improve patient selection for coronary intervention is nowadays undisputed. The fractional flow reserve represents the cornerstone of clinical coronary physiology tools, and has proved to be of substantial diagnostic and prognostic value in daily clinical practice. Nonetheless, it remains only one of several physiological tools available to the practicing clinician. The large armamentarium of physiology tools ranges from conventional coronary pressure-derived indices for stenosis severity assessment to more complex comprehensive physiology tools based on combined assessment of coronary pressure and flow (velocity), which allow selective identification of epicardial and microvascular contributions to myocardial perfusion impairment. With increasing understanding and acknowledgment of a complex multilevel involvement of the coronary circulation in ischemic heart disease, a combination of physiology tools that allow evaluation of the coronary circulation beyond the epicardial stenosis becomes increasingly relevant. This chapter describes the currently available tools to assess coronary physiology and their clinical application in individual patients.