A framework for computational fluid dynamic analyses of patient-specific stented coronary arteries from optical coherence tomography images

Abstract

The clinical challenge of percutaneous coronary interventions (PCI) is highly dependent on the recognition of the coronary anatomy of each individual. The classic imaging modality used for PCI is angiography, but advanced imaging techniques that are routinely performed during PCI, like optical coherence tomography (OCT), may provide detailed knowledge of the pre-intervention vessel anatomy as well as the post-procedural assessment of the specific stent-to-vessel interactions. Computational fluid dynamics (CFD) is an emerging investigational tool in the setting of optimization of PCI results. In this study, an OCT-based reconstruction method was developed for the execution of CFD simulations of patient-specific coronary artery models which include the actual geometry of the implanted stent. The method was applied to a rigid phantom resembling a stented segment of the left anterior descending coronary artery. The segmentation algorithm was validated against manual segmentation. A strong correlation was found between automatic and manual segmentation of lumen in terms of area values. Similarity indices resulted >96% for the lumen segmentation and >77% for the stent strut segmentation. The 3D reconstruction achieved for the stented phantom was also assessed with the geometry provided by X-ray computed micro tomography scan, used as ground truth, and showed the incidence of distortion from catheter-based imaging techniques. The 3D reconstruction was successfully used to perform CFD analyses, demonstrating a great potential for patient-specific investigations. In conclusion, OCT may represent a reliable source for patient-specific CFD analyses which may be optimized using dedicated automatic segmentation algorithms.

A Patient-Specific Study Investigating the Relation between Coronary Hemodynamics and Neo-Intimal Thickening after Bifurcation Stenting with a Polymeric Bioresorbable Scaffold

“…The three-dimensional (3D) geometry of the patient's bifurcation with the implanted Absorb BVS was reconstructed by means of a validated OCT-based methodology [6]. In particular, an automatic segmentation algorithm was implemented to detect the baseline lumen contour and the polymeric scaffold in the baseline OCT image set ( Figure 1A).…”

“…The lumen contours were segmented according to a previously described strategy [6,9]. The pre-processed images were elaborated in polar coordinates and a Sobel filter was applied to detect edges.…”

“…The vessel centerline was extracted from angiographic images that were elaborated with the commercial software CAAS (Pie Medical Imaging BV, Maastricht, The Netherlands). Then, the 3D geometries of the vessel and the scaffold struts were obtained by following a previously developed and validated 3D reconstruction methodology [6]. The surface for the vessel main branch was defined as follows.…”

“…In the present study, we sought to investigate the relation between patient's hemodynamics at baseline and NIT after nine-month from the intervention. A previously validated optical coherence tomography (OCT) based methodology [6] was applied to reconstruct a patient-specific coronary artery at baseline, after the insertion of a bioresorbable polymeric scaffold. The achieved high fidelity geometrical model was used to simulate the blood flow under the effect of the scaffold.…”

The effect of hybrid savonius and darrieus turbine on the change of wake recovery and improvement of wind energy harvesting

“…Combination of CFD and statistic technique has been used to guessspreading of airborne sea salt [31]. The Kruskal-Wallis test used to test statistical differences between lumen areas from CFD result in the medical application of stent coronary artery [32].…”