Utility of Near-Infrared Spectroscopy Intravascular Ultrasound in Predicting the Slow-Flow Phenomenon During Percutaneous Coronary Intervention in Patients With Stable Angina

Abstract

Background: Slow flow caused by distal embolization during percutaneous coronary intervention (PCI) worsens outcomes. Near-infrared spectroscopy with intravascular ultrasound (NIRS-IVUS) can quantify the preoperative lipid burden. We investigated the utility of combining measurement of plaque size and lipid burden.

Methods and Results: We analyzed 91 stable-angina patients undergoing NIRS-IVUS-guided PCI. Slow flow (≥1-grade TIMI decrease) occurred in 17 (18.7%). Those lesions had larger plaque area (13.8 vs. 9.9 mm², P<0.001) and higher maxLCBI_{4 mm}(625 vs. 436, P<0.001). Cutoffs were 12.0 mm²and 523, respectively. Either criterion identified all slow-flow cases (sensitivity 100%).

Conclusions: Combined assessment of plaque area and maxLCBI_{4 mm}enables simple and highly sensitive identification of lesions at risk of slow flow during PCI.