Influence of pullback pressure gradient on patient-reported and clinical outcomes in coronary artery disease

Abstract The pullback pressure gradient (PPG) is a novel metric that complements physiological assessment, quantifying coronary artery disease (CAD) patterns on a scale from 0 (diffuse) to 1 (focal). Pathophysiological patterns of CAD (focal vs diffuse) have been shown to impact the effectiveness of revascularization. This study aimed to assess the impact of PPG on patient-reported and clinical outcomes in stable patients with hemodynamically significant CAD. PPG Global is a prospective, investigator-initiated, single-arm, multicenter study that enrolled patients with at least one lesion with a fractional flow reserve (FFR) ≤ 0.80 intended to be treated with PCI. PPG was calculated from manual FFR pullbacks. Physicians could opt for medical therapy or coronary artery bypass graft (CABG) surgery instead of PCI after PPG calculation. A core laboratory analyzed angiographic and physiological data. Patient-reported outcomes (PROs) were ascertained using the 7-item Seattle Angina Questionnaire (SAQ), administered at baseline and one-year follow-up. The study included 947 patients. The mean age was 67.6±10.2 years, 24% were female, and 29% were diabetic, without differences between focal and diffuse CAD. PCI was performed in 96.9% of patients with focal CAD and 76.1% of patients with diffuse disease (p0.001). Patients with diffuse disease were managed medically in 16.3% of cases, and 7.6% underwent CABG. At one year, patients with focal disease (high PPG) reported a greater improvement in angina, physical limitation, and quality of life compared to those with low PPG (17.4±20.4 vs. 12.7±20.2; 15.3±30.2 vs. 8.4±28.8 and 35.4±31.7 vs. 27.3±32.9 respectively, p≤0.001). PPG was independently associated with angina improvement (p = 0.017). Among patients with angina at baseline (n=612), those with focal CAD reported lower residual angina than diffuse disease at one year (SAQ angina frequency score 95.3±9.9 vs. 92.5±15.0, p=0.006). In patients with diffuse disease (PPG 0.62), there were no differences in residual symptoms at one year between patients treated with PCI, OMT, or CABG (SAQ AF 93.1 ± 14.1 vs. 92.1 ± 12.6 vs. 90.2 ± 19.6, p= 0.474). The one-year TVF rate was similar between patients with focal and diffuse CAD (6.9% vs. 9.1%, p=0.265). When stratified by treatment strategies, patients with diffuse disease treated with PCI had the highest TVF rate driven by a higher incidence of peri-procedural myocardial infarction (PCI focal 7.1%; PCI Diffuse 10.8%; CABG 2.1%; OMT 3.6%; p= 0.028). In patients with significant CAD, the presence of focal disease defined by PPG was associated with greater symptomatic relief at one year compared to diffuse disease (low PPG). Among patients with diffuse CAD, treatment strategies did not significantly impact residual symptoms, suggesting the complex nature of symptom management in this cohort. Further investigation through a randomized trial is warranted to determine the benefit of a PPG-guided PCI strategy.