Comparison of Efficacy and Safety Profile of Intracoronary Sodium Nitroprusside and Intravenous Adenosine for Fractional Flow Reserve Study

Abstract

Objectives: The purpose of this study was to compare the efficacy and safety of intracoronary (IC) nitroprusside and intravenous adenosine (IVA) for assessing fractional flow reserve (FFR). Background: IV infusion of adenosine is a standard method to achieve a coronary hyperemia for FFR measurement. However, adenosine is expensive, causes multiple side effects, and is contraindicated in patients with reactive airway disease. Sodium nitroprusside (NTP) is a strong coronary vasodilator but its efficacy and safety for assessing FFR is not well established. Methods: We compared FFR response and side effects profile of IC NTP and IVA. Bolus of NTP at a dose of 100 lg and IVA (140 lg/kg/min) were used to achieve coronary hyperemia. Results: We evaluated 75 lesions in 53 patients (60% male) mean age 61.6 6 13.9 years. Mean FFR after NTP was similar to FFR after adenosine (0.836 6 0.107 vs. 0.856 6 0.106; P 5 0.26; r 5 0.91, P < 0.001). NTP induced maximal stable hyperemia within 10 sec (mean: 6.4 6 1) which lasted consistently between 38 and 60 sec (mean 51 6 7.5). NTP caused significant (14%), but asymptomatic decrease in mean blood pressure which returned to baseline within 60 sec. Adenosine caused shortness of breath in 26%, headache and flushing in 19%, and transient second degree heart block in 6% of patients. No adverse symptoms were reported after NTP. Conclusions: IC NTP is as effective as IVA for measuring FFR. NTP is better tolerated by patients. Since NTP is inexpensive, readily available, well tolerated, and safe, it may be a better choice for FFR assessment. V C 2012 Wiley Periodicals, Inc.