Incremental Prognostic Value of Post-Intervention Pd/Pa in Patients Undergoing Ischemia-Driven Percutaneous Coronary Intervention

Objectives: This study sought to evaluate the prognostic value of post–percutaneous coronary intervention (PCI) distal coronary pressure to aortic pressure ratio (Pd/Pa) in predicting long-term clinical outcomes and to determine whether Pd/Pa combined with fractional flow reserve (FFR) post-intervention provides additional prognostic information superior to either marker alone. Background: Post-PCI FFR has been shown to be a predictor of long-term outcomes in numerous studies. The role of post-PCI resting Pd/Pa has not been previously studied in this setting. Methods: Consecutive patients undergoing PCI who had pre- and post-PCI Pd/Pa and FFR were followed for major adverse cardiovascular events (MACE) including death, myocardial infarction, and target vessel revascularization. Results: A total of 574 patients were followed for 30 months (25th to 75th percentile 18 to 46 months). Using receiver-operating characteristic curve analysis post-stenting FFR cutoff of ≤0.86 had the best predictive accuracy of MACE (17% vs. 23%; log-rank p = 0.02), whereas post-stenting Pd/Pa ≤0.96 was the best predictor of MACE (15% vs. 24%; log rank p = 0.0006). There was a significant interaction between post-PCI Pd/Pa and FFR on MACE risk such that patients with Pd/Pa ≤0.96 and FFR ≤0.86 had the highest event rate (25%), whereas those with Pd/Pa >0.96 and FFR >0.86 had the lowest event rate (15%), which was not different from patients with Pd/Pa >0.96 and FFR ≤0.86 (17%). In a fully adjusted Cox regression analysis, Pd/Pa was an independent predictor of MACE (hazard ratio: 2.07; 95% confidence interval: 1.3 to 3.3; p = 0.002). Conclusions: Post-PCI resting Pd/Pa is a powerful prognostic tool for MACE prediction. It adds complementary and incremental risk stratification over established factors including post-PCI FFR.