Why is this study important? 

Side branch (SB) occlusion is a risk during unprotected left main (LM) percutaneous coronary intervention (PCI). Understanding the risk factors for SB occlusion can help guide bifurcation stenting strategies and improve outcomes. 

What question was this study supposed to answer? 

To study risk factors for predicting SB occlusion during LM bifurcation PCI.

What did the study show? 

855 patients undergoing provisional stenting strategy for LM disease were included in the current study. SB occlusion, defined as any decrease in Thrombolysis in Myocardial Infarction score (TIMI) flow, occurred in 19 (2.2%) patients after main vessel (MV) stenting.

In the multivariable analysis, MV/SB diameter ratio, MV plaque ipsilateral to SB and baseline SB diameter stenosis were independent predictors for SB occlusion. LM V-RESOLVE risk score was developed based on these three angiographic features with C-statistics of 0.830 (95% CI 0.738-0.92).

Key takeaway 

LM V-RESOLVE scoring system can help predict risk of SB occlusion after MV stenting during unprotected LM PCI. More studies are needed to further optimize LM bifurcation PCI outcomes.