title: Fundamentals in clinical coronary physiology: why coronary flow is more important than coronary pressure.
abstract: Wide attention for the appropriateness of coronary stenting in stable ischaemic heart disease (IHD) has increased interest in coronary physiology to guide decision making. For many, coronary physiology equals the measurement of coronary pressure to calculate the fractional flow reserve (FFR). While accumulating evidence supports the contention that FFR-guided revascularization is superior to revascularization based on coronary angiography, it is frequently overlooked that FFR is a coronary pressure-derived estimate of coronary flow impairment. It is not the same as the direct measures of coronary flow from which it was derived, and which are critical determinants of myocardial ischaemia. This review describes why coronary flow is physiologically and clinically more important than coronary pressure, details the resulting limitations and clinical consequences of FFR-guided clinical decision making, describes the scientific consequences of using FFR as a gold standard reference test, and discusses the potential of coronary flow to improve risk stratification and decision making in IHD.
authors.affiliation: AMC Heart Centre, Academic Medical Center, University of Amsterdam, Room B2-213, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands Department of Biomedical Engineering and Physics, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands t.p.vandehoef@amc.uva.nl.
authors.forename: Tim P
authors.initials: TP
authors.lastname: van de Hoef
authors.affiliation: AMC Heart Centre, Academic Medical Center, University of Amsterdam, Room B2-213, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands Department of Biomedical Engineering and Physics, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
authors.forename: Maria
authors.initials: M
authors.lastname: Siebes
authors.affiliation: AMC Heart Centre, Academic Medical Center, University of Amsterdam, Room B2-213, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands Department of Biomedical Engineering and Physics, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
authors.forename: Jos A E
authors.initials: JA
authors.lastname: Spaan
authors.affiliation: AMC Heart Centre, Academic Medical Center, University of Amsterdam, Room B2-213, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands.
authors.forename: Jan J
authors.initials: JJ
authors.lastname: Piek
mesh_terms: D001783:Blood Flow Velocity / Q000502:physiology; D001794:Blood Pressure / Q000502:physiology; D000066491:Clinical Decision-Making; D003326:Coronary Circulation / Q000502:physiology*; D023921:Coronary Stenosis / Q000175:diagnosis / Q000503:physiopathology; D053805:Fractional Flow Reserve, Myocardial / Q000502:physiology; D006801:Humans; D008833:Microcirculation / Q000502:physiology; D017202:Myocardial Ischemia / Q000175:diagnosis / Q000503:physiopathology*; D009204:Myocardial Revascularization / Q000706:statistics & numerical data; D018579:Patient Selection
keywords: Coronary flow; Coronary flow reserve; Coronary pressure; Fractional flow reserve; Ischaemic heart disease