Stent Underexpansion Prediction Is Improved by Intravascular Ultrasound-Based Distance-Averaged Calcium Angles

Area of Science:

• Cardiology
• Medical Imaging
• Interventional Cardiology

Background:

• Calcified coronary lesions are key predictors of stent underexpansion.
• Intravascular ultrasound (IVUS)-based maximum calcium angle is a known predictor.

Purpose of the Study:

• To assess if distance-averaged calcium angles from IVUS correlate with stent underexpansion.
• To compare the predictive accuracy of distance-averaged angles versus maximum calcium angle.

Main Methods:

• Retrospective analysis of 292 patients undergoing IVUS-guided PCI with drug-eluting stents.
• IVUS assessed calcified plaque angles every 1 mm within 5 mm of the maximum calcium site.
• Stent underexpansion defined as <70% stent expansion.

Main Results:

• Distance-averaged calcium angles significantly correlated with stent underexpansion in 87 cases.
• Area under the curve (AUC) for prediction ranged from 0.75 to 0.77.
• 2 mm-averaged calcium angles showed high predictive accuracy (AUC 0.77) without significant improvement from longer distances.

Conclusions:

• Distance-averaged calcium angles effectively predict stent underexpansion.
• This method offers improved prediction compared to the maximum calcium angle alone.
• 2 mm-averaged calcium angles provide a practical and accurate approach for predicting stent underexpansion.