Stent geometry achieved by stepwise provisional stenting in left main trifurcation: Bench-test comparison of different side-branch intervention techniques

Background: Left main coronary trifurcations pose specific challenges for percutaneous coronary intervention due to complex anatomy and lack of standardized approaches. Aims: We assess to evaluate the stent conformations achieved by different adaptations to trifurcations of stepwise provisional stenting in a bench test. Methods: Percutaneous coronary intervention procedures were performed in silicon trifurcation models using standard equipment. After main vessel stenting and proximal optimization technique, side branch (SB) rewiring was conducted via same-cell (SAC) or neighbouring-cell (NEC) under optical coherence tomography guidance. SBs dilation was then performed using either simultaneous trissing or serial kissing balloon techniques. Following repeat proximal optimization technique, stent expansion and apposition were assessed with optical coherence tomography and micro-computed tomography. Results: All 4 technique combinations were feasible and resulted in satisfactory stent expansion and apposition. Micro-computed tomography analysis showed that trissing improved expansion at the polygon of confluence compared to serial kissing (23.7 vs. 21.1 mm²; P = 0.043), while SAC rewiring yielded better expansion at the distal main vessel ostium than NEC (10.3 vs. 9.6 mm²; P = 0.003). Rewiring technique determined the conformation of the stent at the level of SBs take-off: NEC produced 2 stent fenestrations and SAC a single stent fenestration (with a minimal area significantly smaller than the sum of the 2 achieved by NEC: 16.4 mm² vs. 13.4 + 14.5 mm²; P = 0.019). Conclusions: All provisional stenting strategies tested were technically feasible for left main trifurcations. SB rewiring and ballooning technique influenced stent configuration, particularly the number and size of fenestrations, but had limited impact on overall stent expansion and apposition.