Feasibility of intracoronary nicorandil for inducing hyperemia on fractional flow reserve measurement: Comparison with intracoronary papaverine

Background Adenosine and adenosine triphosphate (ATP) are widely used to induce hyperemia for fractional flow reserve (FFR) measurements. Caffeine attenuates their hyperemic effects, but not those of nicorandil and papaverine. No studies have systematically compared the hyperemic efficacies of nicorandil, papaverine, and ATP with and without caffeine abstention. Methods FFRs were measured using nicorandil 2 mg (FFRNC2), nicorandil 4 mg (FFRNC4), and papaverine (FFRPAP) in 40 patients (group 1), and using nicorandil 2 mg, ATP (FFRATP), ATP plus nicorandil (FFRATP+NC2), and papaverine in 20 patients with (group 2) and in 20 patients without caffeine abstention (group 3). Results In group 1, FFRNC2 and FFRNC4 did not differ (p = 0.321) and were higher than FFRPAP (p Conclusions Nicorandil 2 mg is a safe and practical alternative for patients who consume caffeine-containing products before the test or have contraindications for adenosine/ATP. Increasing the nicorandil dose to 4 mg or administering adjunctive nicorandil during ATP infusions does not offer any clinical advantages compared with administering nicorandil 2 mg alone.