Table 1 Importance of epicardial and microvascular vasodilatation when measuring fractional flow reserve

Epicardial vasodilation
Isosorbide dinitrate: at least 200 μg ic bolus, at least 30 s before the first measurements
Microvascular vasodilation
Adenosine or ATP ic	50 μg ic bolus
Papaverine ic	8 mg in the RCA, 12 mg in the LCA
Nitroprusside ic	0.6 μg/kg in bolus
Adenosine or ATP iv	140 μg/kg/min (preferably through a central venous, eg, femoral line)

ATP, adenosine triphosphate; ic, intracoronary; iv, intravenously, RCA, right coronary artery; LCA, left coronary artery.