How to Apply Physiology-Guided Percutaneous Coronary Intervention Optimization?: Theory and Practice

Angiography-guided percutaneous coronary intervention (PCI) provides symptom relief and improve clinical outcome in patients with myocardial ischemia.However, about 30% of patients still have recurrent angina at 1 year or major adverse cardiac events at 2 years despite angiographically successful PCI.Therefore, angiography-guided PCI alone has limited efficacy to identify suboptimal PCI results.Invasive coronary physiological assessment has been regarded as a reference tool to evaluate the degree of myocardial ischemia and differentiate patients in need of PCI.Furthermore, it has been well known that physiologyguided PCI improve clinical outcome.Among physiology indices, fractional flow reserve (FFR) and non-hyperemic pressure ratios (NHPRs) such as instantaneous wave-free ratio, diastolic hyperemia-free ratio, diastolic pressure ratio, and resting full-cycle ratio as well as resting distal coronary pressure to aortic pressure ratio have been widely used as representative invasive coronary physiologic parameters.However, the adoption of FFR and NHPRs remained still low both before and after PCI in real-world practice.Recent clinical studies have extended the role of physiological assessment from pre-PCI lesion evaluation to evaluating the success of post-PCI procedures.The concept of "post-PCI functional optimization" may increase the adoption of coronary physiological assessment through expanding clinical benefit.In this review, we will investigate 1) evolving evidence for performing coronary physiological assessment after PCI beyond pre-PCI decision making, 2) practical guidance for physiology-guided PCI optimization, and 3) practical considerations and future perspectives of physiology-guided PCI optimization.