Confirmation of maximal hyperemia by the incremental dose of intracoronary papaverine.

We investigated the effect of the papaverine dose increment method to confirm maximal hyperemia for fractional flow reserve (FFR) measurements. We evaluated 115 consecutive patients involving 200 lesions. FFR was measured after intracoronary papaverine injection into the left (12 mg) and right (8 mg) coronary arteries as standard doses. Except for 2 patients who had ventricular tachyarrythmia (VTA), we administered a higher papaverine dose (2 mg added to the standard dose). We compared the FFR values after using different papaverine doses. VTA incidence and electrocardiogram parameters were compared according to the papaverine doses used. The QTU interval and corrected QTU were significantly prolonged after using a higher dose compared with a standard dose. VTA occurred in one patient (0.9%) at the higher dose. There was no significant difference with a strong correlation between the FFR values in the 2 doses (r = 0.963, P < 0.001). Maximal hyperemia was achieved in most patients at the standard papaverine dose. However, 19 lesions changed ischemic diagnosis at the higher dose (12 lesions changed from ischemia negative to positive, and 7 lesions changed from positive to negative). Therefore, to confirm the appropriate ischemia diagnosis for borderline FFR values, it may be favorable to perform another FFR measurement at an incremental papaverine dose.