TCT-724 Impact of the pullback pressure gradient on coronary flow reserve.

Abstract

Background: Coronary flow reserve (CFR) quantifies the extent to which blood flow can increase in response to a hyperemic stimulus. The presence of epicardial disease reduces CFR. However, the impact of coronary artery disease (CAD) disease patterns (focal vs diffuse) on CFR remains poorly understood. We aimed to determine the impact on CFR of CAD patterns quantified using the pullback pressure gradient (PPG) during hyperemia. Method(s): This prospective, investigator-initiated, single-arm, multicenter study enrolled patients with at least 1 epicardial lesion planned for PCI having a fractional flow reserve (FFR) <=0.80. A manual hyperemic pullback with PPG calculation was performed before PCI. High PPG values (close to 1) indicate focal disease, while low PPG values (near 0) signal diffuse disease. CFR was calculated as the ratio between resting and hyperemic mean transit times using bolus thermodilution. Result(s): Overall, 242 patients (248 vessels) were included in this analysis. The mean age was 68 +/- 10 years; 73% were male, and 35% had diabetes. The left anterior descending artery was the target vessel in 82%. The mean FFR, PPG, and CFR were 0.70 +/- 0.13, 0.62 +/- 0.16, and 2.4 +/- 1.2, respectively. Patients with predominantly focal disease (PPG > 0.62 median) exhibited significantly lower CFR compared with those with diffuse disease (CFR 2.2 +/- 1.1 vs 2.6 +/- 1.25, P = 0.005). Following PCI, the improvement in CFR was significantly greater in patients with high PPG (DELTACFR 0.77, IQR [0.14 to 2.11] focal vs 0.11 IQR [-0.78 to 1.10] diffuse P < 0.001). There was a significant correlation between PPG and DELTACFR (r = 0.22; 95% CI: 0.06-0.037; P = 0.007). Consequently, post-PCI CFR was higher in patients with focal vs diffuse disease (CFR 3.4 +/- 2.0 vs 2.7 +/- 1.5; P = 0.025). Conclusion(s): Epicardial CAD patterns influence CFR. Patients with a predominant focal disease exhibited a significantly lower CFR than those with diffuse disease. CFR improvement after PCI was significantly greater in patients with predominantly focal vs diffuse atherosclerosis. Categories: IMAGING AND PHYSIOLOGY: Physiologic Lesion Assessment.Copyright © 2024