ABSTRACT
Fractional flow reserve (FFR) is considered the gold standard for invasively assessing the physiologic significance of coronary artery stenosis. This technique has become an integral adjunct to coronary angiography for identifying ischaemic lesions and an invaluable tool in guiding clinical decision making regarding revascularisation. Despite convincing evidence supporting FFR-guided revascularisation, physiological lesion assessment is underutilised in real-world practice. FFR is defined as the ratio of myocardial blood flow in a coronary artery in the presence of epicardial stenosis and myocardial blood flow in the same artery in the hypothetical absence of stenosis under conditions of maximal hyperaemia. The central concept to measurement of FFR is the assumption that coronary blood flow is proportional to pressure when myocardial resistance is minimal and constant. Several randomised trials proved favourable for long-term clinical outcomes with deferral of revascularisation based on FFR in patients with stable CAD.
