A large, prospective, multicenter trial recently showed that fractional flow reserve (FFR) derived from coronary angiography (FFRangio) has an accuracy of 92% compared with conventional guide-wire based FFR (FFRwire); however, little is known whether specific patient/lesion characteristics affect the diagnostic performance.
FFRangio was measured in a blinded fashion in 301 patients (319 vessels) who were undergoing FFRwire assessment. Using an FFRwire ≤0.80 as a reference, the diagnostic performance of FFRangio was compared in pre-specified subgroups. The mean FFRwire and FFRangio were 0.81 ± 0.13 and 0.80 ± 0.12. Overall, FFRangio had a sensitivity of 93.5% and specificity of 91.2% for predicting FFRwire. Patient characteristics including age, sex, clinical presentation, body mass index, and diabetes did not affect sensitivity or specificity (p>0.05 for all). Similarly, lesion characteristics including calcification, tortuosity did not affect sensitivity or specificity (p>0.05 for all), nor did lesion location (proximal, middle, versus distal). Sensitivity was equally high across all target vessels, while specificity was highest in the LAD and lower (~85%) in the RCA and LCx (p<0.05).
FFRangio derived from coronary angiography has a high diagnostic performance regardless of patient and most lesion characteristics. The interaction of vessel on the specificity will need to be confirmed in larger cohorts.