Usefulness of intervention using interlesion pressure ratio in renal artery stenosis due to multifocal fibromuscular dysplasia: a case report

This case demonstrates the clinical utility of Pd/Pa ratio as a physiological endpoint in PTRA for FMD-related RAS. Multifocal FMD, angiographic assessment may underestimate haemodynamic improvement; however, a substantial increase in the Pd/Pa ratio, even below the conventional 0.90 threshold, may indicate procedural success. Applying the Pd/Pa ratio may avoid stenting in small-calibre vessels and favour long-term BP control.