A Y-shaped bifurcation-dedicated stent for the treatment of de novo coronary bifurcation lesions: an IVUS analysis from the BRANCH trial

Double kissing mini-culotte versus mini-culotte stenting: insights from micro-computed tomographic imaging of bench testing

AIMS

This study aimed to evaluate the morphologic characteristics of double kissing (DK) mini-culotte and mini-culotte stenting through imaging of bench testing.

METHODS AND RESULTS

DK mini-culotte and mini-culotte stenting were performed in two silicone bifurcated phantoms with branch vessel diameter differences of 0.5 mm (Model 1) and 1.25 mm (Model 2), and their morphologic characteristics were evaluated by micro-computed tomography. In Model 1, metal carina length (0.25±0.13 mm vs 0.55±0.15 mm), area stenosis of the side branch ostium (SBO) (4.65±3.24% vs 12.5±3.93%), and maximum distance of malapposed struts for the wall facing the SBO (0.27±0.08 mm vs 0.49±0.15 mm) were lower in the DK mini-culotte group than in the mini-culotte group. In Model 2, metal carina length (0.21±0.47 mm vs 0.47±0.12 mm), SBO area stenosis (5.13±3.37% vs 15.00±6.18%), and maximum distance of malapposed struts (0.32±0.13 mm vs 0.68±0.10 mm) were also lower in the DK mini-culotte group. The results of factorial analysis showed that maximum distance of malapposed struts tended to be shorter in Model 1 (F=4.226, p=0.062).

CONCLUSIONS

Compared with mini-culotte stenting, DK mini-culotte stenting was associated with shorter metal carina length, shorter maximum distance of malapposed struts, and smaller SBO area stenosis. Thus, DK mini-culotte stenting may obtain better morphologic characteristics.

Branch ostial optimization treatment and optimized provisional t-stenting with polymeric bioresorbable scaffolds: Ex-vivo morphologic and hemodynamic examination

The optimal side-branch (SB) ostium treatment after provisional side-branch scaffolding remains a subject of debate in bioresorbable vascular scaffold (BVS) era. In this study, we evaluated a novel optimized provisional T-stenting technique (OPT) and assessed its feasibility by comparison with T and small protrusion technique (TAP).Two provisional SB scaffolding techniques (OPT, n = 5; TAP, n = 5) were performed using polymeric BVS in a bifurcated phantom. The sequential intermediate snuggling balloon dilation, also called ostial optimal technique, was added to OPT but not TAP to dilate the side-branch ostium while the final snuggling balloon dilation applied for both procedures. Microcomputed tomography (microCT) and optical coherence tomography (OCT) were performed to assess morphology, and computational fluid dynamics (CFD) was performed to assess hemodynamics in the scaffolded bifurcations. Compared with TAP in microCT analysis, OPT created shorter neo-carina length than TAP (0.34 ± 0.10 mm vs 1.02 ± 0.26 mm, P < .01), longer valgus struts length (2.49 ± 0.27 mm vs 1.78 ± 0.33 mm, P < .01) with larger MB ostial area (9.46 ± 0.04 mm vs 8.34 ± 0.09 mm, P < .01). OCT found that OPT significantly decreased the struts mal-apposition (13.20 ± 0.16% vs 1.94 ± 0.54%, P < .01). CFD revealed that OPT generated more favorable flow pattern than TAP, as indicated by less percent (4.68 ± 1.40% vs 8.88 ± 1.21%, P < .01) of low wall shear stress (<0.4 Pa) along the lateral walls.By using BVSs for bifurcation intervention, the sequential intermediate snuggling balloon dilation is feasible for optimizing ostial SB and facilitating subsequent SB scaffolding. Results show OPT is better than TAP for bifurcated morphology and hemodynamics in this ex-vivo study.

Clinical Outcome of Double Kissing Crush Versus Provisional Stenting of Coronary Artery Bifurcation Lesions: The 5-Year Follow-Up Results From a Randomized and Multicenter DKCRUSH-II Study (Randomized Study on Double Kissing Crush Technique Versus Provisional Stenting Technique for Coronary Artery Bifurcation Lesions)

BACKGROUND

Provisional stenting is effective for anatomic simple bifurcation lesions. Double kissing crush stenting reduces the 1-year rate of target lesion revascularization. This study aimed to investigate the 5-year clinical results of the DKCRUSH-II study (Randomized Study on Double Kissing Crush Technique Versus Provisional Stenting Technique for Coronary Artery Bifurcation Lesions).

METHODS AND RESULTS

A total of 370 patients with coronary bifurcation lesions who were randomly assigned to either the double kissing crush or provisional stenting group in the DKCRUSH-II study were followed for 5 years. The primary end point was the occurrence of a major adverse cardiac event at 5 years. Patients were classified by simple and complex bifurcation lesions according to the DEFINITION criteria (Definitions and Impact of Complex Bifurcation Lesions on Clinical Outcomes After Percutaneous Coronary Intervention Using Drug-Eluting Stents). At 5 years, the major adverse cardiac event rate (23.8%) in the provisional stenting group was insignificantly different to that of the double kissing group (15.7%; P=0.051). However, the difference in the target lesion revascularization rate between 2 groups was sustained through the 5-year follow-up (16.2% versus 8.6%; P=0.027). The definite and probable stent thrombosis rate was 2.7% in each group (P=1.0). Complex bifurcation was associated with a higher rate of target lesion revascularization (21.6%) at 5 years compared with 11.1% in patients with a simple bifurcation (P=0.037), with an extremely high rate in the provisional stenting group (36.8% versus 12.5%, P=0.005) mainly because of final kissing balloon inflation (19.4% versus 5.2%; P=0.036).

CONCLUSIONS

The double kissing crush stenting technique for coronary bifurcation lesions is associated with a lower rate of target lesion revascularization. The optimal stenting approach based on the lesions' complexity may improve the revascularization for patients with complex bifurcations.

CLINICAL TRIAL REGISTRATION

URL: http://www.chictr.org. Unique identifier: ChiCTR-TRC-0000015.