Physiologic Assessment of Coronary Stenosis: Current Status and Future Directions.

Percutaneous coronary intervention (PCI) is a commonly used treatment option in coronary artery disease (CAD). Reduced major adverse cardiovascular events (MACE) in those randomized to PCI compared to optimal medical therapy have been demonstrated only if it is performed for physiologically significant coronary lesions. Despite data demonstrating improved outcomes primarily in stable CAD and then acute settings, physiology-guided PCI remains underutilized. This review summarizes the evidence and commonly used methods for physiologic assessment of coronary stenosis. Fractional flow reserve (FFR) is the gold standard for the analysis of lesion severity. Its use is limited by the need for adenosine, which adds time, complexity, and potential adverse effects. Non-hyperemic instantaneous wave-free ratio-guided revascularization and quantitative flow reserve ratio assessment both have shown safety and effectiveness with improved patient outcomes. Coronary physiological assessment solves the ambiguity of coronary angiography. Detecting physiologically significant stenoses is crucial to decide which lesion needs to be treated. Technological advances have led to the development of new assessment indices in addition to FFR.