Postdilation Strategies Following Provisional Stenting of Left Main Coronary Bifurcations: Insights From Patient-Specific Computational Simulations

Background
Provisional stenting is the preferred percutaneous coronary intervention strategy for noncomplex left main (LM) bifurcations; yet, the optimal postdilation strategy remains debated.

Objectives
The objective of the study was to quantitatively compare postdilation techniques following LM provisional stenting using validated computational simulations.

Methods
Four patient-specific LM bifurcations were reconstructed in three dimensions and virtually stented. Seven postdilation techniques were evaluated: 1) standard proximal optimization technique (POT; P); 2) POT and simultaneous kissing balloon inflation (KBI); 3) POT and simultaneous KBI and re-POT; 4) POT and sequential KBI; 5) POT plus sequential and simultaneous KBI; 6) POT plus sequential and simultaneous KBI with re-POT; and 7) POT plus left circumflex dilation and re-POT (P-S-P). Techniques were compared based on lumen/stent morphology and hemodynamics.

Results
P ranked lowest overall, resulting in 27% smaller ostial area, 59% greater stent jailing, and 76% larger area exposed to high wall shear stress gradient at the left circumflex ostium compared with other techniques. P-S-P ranked second lowest, yielding 14% smaller ostial area and 29% greater area exposed to high relative residence time at the left anterior descending artery ostium. Techniques incorporating KBI showed the most favorable performance, with combined sequential and simultaneous KBI performing best, particularly in calcified or fibrous plaques. Final POT after KBI did not confer incremental benefit.

Conclusions
KBI is superior to P or P-S-P. Combined high-pressure sequential and nominal-pressure simultaneous KBI outperforms sequential or simultaneous KBI alone, particularly in stiff calcified or fibrous lesions. Final POT after KBI provides no incremental advantage.