Geographic disparity of pathophysiological coronary artery disease characteristics: Insights from ASET trials

Background: The geographical disparity in the pathophysiological pattern of coronary artery disease (CAD) among patients undergoing percutaneous coronary intervention (PCI) is unknown. Objectives: To elucidate the geographical variance in the pathophysiological characteristics of CAD. Methods: Physiological indices derived from angiography-based fractional flow reserve pullbacks from patients with chronic coronary syndrome enrolled in the ASET Japan (n = 206) and ASET Brazil (n = 201) studies, which shared the same eligibility criteria, were analysed. The pathophysiological patterns of CAD were characterised using Murray law -based quantitative flow ratio (mu QFR)-derived indices acquired from pre-PCI angiograms. The diffuseness of CAD was defined by the mu QFR pullback pressure gradient index. Results: Significant functional stenoses pre-PCI (mu QFR <= 0.80) were more frequent in ASET Japan compared to ASET Brazil (89.9% vs. 67.5%, p < 0.001), as were rates of a post-PCI mu QFR <0.91 (22.1% vs. 12.9%, p = 0.013). In the multivariable analysis, pre -procedural mu QFR and diffuse disease were independent factors for predicting a post-PCI mu QFR <0.91, which contributed to the different rates of post-PCI mu QFR >= 0.91 between the studies. Among vessels with a post-PCI mu QFR <0.91, a consistent diffuse pattern of CAD pre- and post-PCI occurred in 78.3% and 76.7% of patients in ASET Japan and Brazil, respectively; only 6.3% (Japan) and 10.0% (Brazil) of vessels had a major residual gradient. Independent risk factors for diffuse disease were diabetes mellitus in ASET Japan, and age and male gender in Brazil. Conclusions: There was geographic disparity in pre -procedural angiography-based pathophysiological characteristics. The combined pre -procedural physiological assessment of vessel mu QFR and diffuseness of CAD may potentially identify patients who will benefit most from PCI.