The "crush" technique for coronary artery bifurcation stenting: insights from micro-computed tomographic imaging of bench deployments.

OBJECTIVES This study provides insights into "crush" coronary bifurcation stenting through imaging of bench deployments. BACKGROUND Although the strategy of provisional side-branch stenting is widely accepted for suitable bifurcation lesions, there is no consensus on the best option for elective stenting with 2 stents. The crush technique has the potential to scaffold and apply the drug to the side-branch ostium where restenosis is most common. METHODS Sequential steps of crush stent deployment and post-dilation were undertaken in silicone phantoms and recorded on cine angiography and microcomputed tomography. We assessed the effect of deployment strategies, post-dilation strategies, and cell size on side-branch ostial area. RESULTS Side-branch ostial coverage by metal struts was 53% (95% confidence interval [CI]: 46 to 59) after 1-step kissing post-dilation and was reduced by 2-step kissing post-dilation to 33% (95% CI: 28 to 37; p < 0.0001). Although the residual stenosis after the classical crush strategy was 47% (95% CI: 39 to 53), it was 36% (95% CI: 31 to 40; p = 0.002) after mini-crush deployment. Stents with larger cell size (>3.5 mm diameter) had a residual stenosis of 37% (95% CI: 32 to 42) after crush deployment that was less than the residual stenosis for stents with smaller cell size (52%; 95% CI: 44 to 60; p < 0.0001). CONCLUSIONS Side-branch ostial stenosis after crush stenting was minimized by mini-crush deployment, 2-step kissing post-dilation, and the use of stents with larger cell size. It is unknown if optimizing stent deployment at bifurcation lesions will reduce clinical stent thrombosis and restenosis.