Prognostic Implications of Post-Intervention Resting Pd/Pa and Fractional Flow Reserve in Patients With Stent Implantation

Objectives This study sought to investigate the prognostic implications of post–percutaneous coronary intervention (PCI) nonhyperemic pressure ratios compared with that of post-PCI fractional flow reserve (FFR). Background FFR measured after PCI has been shown to possess prognostic implications. However, the prognostic value of post-PCI nonhyperemic pressure ratios has not yet been clarified. Methods A total of 588 patients who underwent PCI with available both post-PCI FFR and resting distal coronary pressure-to-aortic pressure ratio (Pd/Pa) were analyzed. Post-PCI FFR and Pd/Pa were measured after successful angiographic stent implantation. The primary outcome was target vessel failure (TVF) up to 2 years, defined as a composite of cardiac death, target vessel–related myocardial infarction, and clinically driven target vessel revascularization. Prognosis of patients according to post-PCI Pd/Pa was compared with that of post-PCI FFR. Results Despite angiographically successful PCI, 18.5% had post-PCI FFR ≤0.80 and 36.9% showed post-PCI Pd/Pa ≤0.92. In post-PCI Pd/Pa >0.92 group, 93.8% of patients showed post-PCI FFR >0.80. Conversely, 60.4% of patients showed post-PCI FFR >0.80 in post-PCI Pd/Pa ≤0.92 group. Although there was significant difference in TVF according to post-PCI FFR (≤0.80 vs. >0.80: 10.3% vs. 2.5%; p 0.92: 6.2% vs. 2.5%; p = 0.029), the reclassification ability of model for TVF was increased only with post-PCI FFR (net reclassification index 0.627; p = 0.003; integrated discrimination index 0.019; p = 0.015), but not with post-PCI Pd/Pa, compared with model including clinical factors. Compared with patients with post-PCI Pd/Pa >0.92, patients with post-PCI Pd/Pa ≤0.92 and FFR ≤0.80 had significantly higher risk of TVF (10.4% vs. 2.5%; adjusted hazard ratio: 4.204; 95% confidence interval: 1.521 to 11.618; p = 0.006); however, those with post-PCI Pd/Pa ≤0.92 but FFR >0.80 showed similar risk of TVF (3.5% vs. 2.5%; adjusted hazard ratio: 1.327; 95% confidence interval: 0.398 to 4.428; p = 0.645). Conclusions Over one-half of the patients with abnormal post-PCI Pd/Pa ≤0.92 showed post-PCI FFR >0.80. Compared with post-PCI FFR, post-PCI Pd/Pa showed limited reclassification ability for the occurrence of TVF. Among patients with abnormal post-PCI Pd/Pa, only patients with positive post-PCI FFR showed significantly higher risk of TVF than did those with post-PCI Pd/Pa >0.92. (Prognostic Perspective of Invasive Hyperemic and Non-Hyperemic Physiologic Indices Measured After Percutaneous Coronary Intervention [PERSPECTIVEPCI]; NCT04265443)