Effectiveness and clinical impact of functional post-PCI optimization-a systematic review and individual patient-data meta-analysis

Background: Suboptimal post-PCI FFR values are associated with impaired clinical outcomes. The determinants and clinical impact of FFR improvement through optimization remain unclear. This study sought to evaluate the effect of post-PCI optimization on fractional flow reserve (FFR) values and to identify predictors of successful optimization. Methods: We performed a systematic review and individual patient data (IPD) meta-analysis including patients who underwent PCI with drug-eluting stents with paired FFR measurements before and after post-PCI optimization. A one-stage meta-analysis was performed using mixed-effects models. The primary endpoint was the absolute increase in FFR after optimization. Results: Out of 1945 screened studies, a total of 11 studies met the selection criteria for the present meta-analysis and IPD was provided from 8 studies. In 314 patients, the median (interquartile range) FFR value significantly improved from 0.81 (0.75-0.85) to 0.86 (0.81-0.89) after optimization (p < 0.001). In multivariable analysis, LAD vessel and higher post-PCI FFR values were negative predictors for the magnitude of FFR increase, whereas optimization using an additional stent was associated with a larger FFR increase as compared to post-dilatation alone. The effect of additional stenting was more pronounced in patients with lower post-PCI FFR values. Conclusions: Post-PCI optimization after angiographically successful PCI resulted in a significant increase in post-PCI FFR. The success of optimization of suboptimal FFR values was associated with target vessel location, initial post-PCI FFR value and optimization method. Keywords: Fractional flow reserve; PCI optimization; Percutaneous coronary intervention.