RT Journal Article SR Electronic T1 Assessment of coronary physiology – the evidence and implications JF Clinical Medicine JO Clin Med FD Royal College of Physicians SP 364 OP 368 DO 10.7861/clinmed.2018-0398 VO 19 IS 5 A1 Noman Ali A1 Peysh A Patel A1 Christopher J Malkin YR 2019 UL http://www.rcpjournals.org/content/19/5/364.abstract AB Use of angiography for the assessment of coronary lesions is limited by its inability to provide information regarding the functional significance of stenoses. A number of studies have demonstrated the presence of ischaemia to be the most important determinant of the benefit associated with coronary revascularisation in stable coronary artery disease. Assessment of intra-coronary physiology can guide percutaneous coronary intervention, and is often used for angiographically borderline stenoses. There is now increasing evidence to suggest that more routine use can improve clinical outcomes. Fractional flow reserve (FFR) is the most established measure of intra-coronary physiology, but is currently under-utilised. The main drawback of FFR is the dependence on a pharmacological infusion to maintain hyperaemia. An alternative technique which measures flow at a specific point in the cardiac cycle (instantaneous wave-free ratio) has been developed which obviates the need for hyperaemia and may replace FFR as the default measure.