Expansion of the Multi-Link Frontier™ Coronary Bifurcation Stent: Micro-Computed Tomographic Assessment in Human Autopsy and Porcine Heart Samples

BACKGROUND: Treatment of coronary bifurcation lesions remains challenging, beyond the introduction of drug eluting stents. Dedicated stent systems are available to improve the technical approach to the treatment of these lesions. However dedicated stent systems have so far not reduced the incidence of stent restenosis. The aim of this study was to assess the expansion of the Multi-Link (ML) Frontier™ stent in human and porcine coronary arteries to provide the cardiologist with useful in-vitro information for stent implantation and selection. METHODOLOGY/PRINCIPAL FINDINGS: Nine ML Frontier™ stents were implanted in seven human autopsy heart samples with known coronary artery disease and five ML Frontier™ stents were implanted in five porcine hearts. Proximal, distal and side branch diameters (PD, DD, SBD, respectively), corresponding opening areas (PA, DA, SBA) and the mean stent length (L) were assessed by micro-computed tomography (micro-CT). PD and PA were significantly smaller in human autopsy heart samples than in porcine heart samples (3.54±0.47 mm vs. 4.04±0.22 mm, p = 0.048; 10.00±2.42 mm(2) vs. 12.84±1.38 mm(2), p = 0.034, respectively) and than those given by the manufacturer (3.54±0.47 mm vs. 4.03 mm, p = 0.014). L was smaller in human autopsy heart samples than in porcine heart samples, although data did not reach significance (16.66±1.30 mm vs. 17.30±0.51 mm, p = 0.32), and significantly smaller than that given by the manufacturer (16.66±1.30 mm vs. 18 mm, p = 0.015). CONCLUSIONS/SIGNIFICANCE: Micro-CT is a feasible tool for exact surveying of dedicated stent systems and could make a contribution to the development of these devices. The proximal diameter and proximal area of the stent system were considerably smaller in human autopsy heart samples than in porcine heart samples and than those given by the manufacturer. Special consideration should be given to the stent deployment procedure (and to the follow-up) of dedicated stent systems, considering final intravascular ultrasound or optical coherence tomography to visualize (and if necessary optimize) stent expansion

Final kissing balloon inflation: the whole story

International audienceFinal kissing balloon inflation (KBI) after provisional bifurcation stenting has failed to provide clear clinical benefit except for a decrease in side branch stenosis, while a significant reduction of major adverse cardiac events has been documented in two-stent deployment. The optimisation of KBI in terms of proximal optimisation technique, appropriate guidewire re-crossing, minimal balloon overlapping, and balloon size selection may overcome the drawbacks of conventional KBI by: 1) correcting the proximal malapposition expected from fractal geometry; 2) optimising side branch ostium strut opening while conserving a bifurcation area free of malapposition at both the carina and the side branch ostium; and 3) optimising the geometry, velocity fields and shear rate

Coronary bifurcation stenting: insights from in-vitro and virtual bench testing

The various techniques and devices that have been proposed for the treatment of coronary bifurcation lesions have differing levels of complexity and each has one or more limitations. Two highly complementary ex-vivo methods are available to study the treatment of bifurcation lesions: in-vitro and virtual bench testing. Both methods can be used to develop, evaluate and optimize bifurcation stenting techniques and dedicated devices. The basics, the evolution, the advantages and limitations of both methods are discussed in this paper. Subsequently, a literature overview of the main insights gained from ex-vivo testing in the field of bifurcation stenting is given