Ex vivo mono-ring technique simplifies culotte stenting for treatment of true bifurcation lesions: Insights from bench testing and clinical application

BACKGROUND: Despite various culotte-based stenting techniques available clinically, the optimal one remains undetermined. The study aimed to test whether ex vivo mono-ring culotte stenting (MRC) was technically feasible and superior to mini culotte stenting (MCS) in treatment of coronary bifurcation lesions. METHODS: Mono-ring culotte stenting was characterized by ex vivo wiring of the most proximal cell of the side branch (SB) stent to ensure a mono-ring result of the culotte stenting. Comparison of MRC vs. MCS in treatment of true bifurcation lesions was performed in vitro (n = 15 for each group) and in clinical case-controlled study with propensity matching at a ratio of 1:2 (n = 21 for MRC group; n = 42 for MCS group). RESULTS: Compared to MCS, MRC had lower incidence of stent under-expansion band (0% vs. 53.3%, p = 0.002) and less residual ostial area stenosis of SB (9.2 ± 9.0% vs. 20.0 ± 14.8%, p = 0.023), as assessed in vitro by micro-computed tomography. In a case-controlled study, no adverse cardiac events were observed in the MRC group. The procedural success was similar between MRC and MCS (100% vs. 95.2%, p = 0.548), but MRC had less residual ostial stenosis of the SB (8.7% ± 11.0% vs. 16.8% ± 11.2%, p = 0.008), lower procedural (33.3 ± 9.5 min vs. 46.7 ± 15.6 min, p = 0.001) and fluoroscopic (19.7 ± 4.9 min vs. 26.2 ± 7.1 min, p < 0.001) time, and less contrast use (114.3 ± 28.9 mL vs. 156.5 ± 56.4 mL, p = 0.002). CONCLUSIONS: Mono-ring culotte stenting as compared to MCS is associated with better bifurcation stent morphology, less procedural complexity and residual ostial SB stenosis.