Recommendations
iFR was originally described as an adenosine-independent index of stenosis severity, but it has since been unequivocally demonstrated otherwise. The use of iFR is promoted by some groups on the grounds that the loss of diagnostic accuracy is an acceptable price to pay in return for reducing (hybrid iFR/FFR) or avoiding altogether (binary iFR) the need to use adenosine. Given the large evidence base for FFR that establishes clinical efficacy, cost-effectiveness and prognostic benefit, we do not consider this to be an acceptable trade-off. Beyond this, there are currently no clinical outcome studies with iFR. As such, it is counterintuitive and contrary to current clinical guidelines to recommend iFR over FFR. IV adenosine is the gold standard technique for inducing steady state maximal hyperaemia, but if operators do not wish to use it due to concerns over cost, time or side-effects, we suggest a policy of high-dose IC adenosine, which should minimise procedural delays as well as costs while providing high-quality data with minimal adverse effects. Healthcare providers need to examine their reimbursement policies to enable cardiologists to utilise this proven adjunct to PCI to the benefit of patients without financially stressing their institutions.