Difference Between Low‐Speed and High‐Speed Rotational Atherectomy Using Two Types of Guidewires

Figures

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  FIGURE 1. The in vitro experimental system in this study. (A) This figure illustrates the manufacturing process of the Heartroid® system. The heart model was created by 3D printer in basis of the real human heart imaged by computed tomography scanner. (B) The heart model was connected to the circulation pump. This circulation pump plays a key role of the pulsatile heart model and enables simulation like the real percutaneous coronary intervention. (C) The calcification model was inserted into the mid of left anterior descending in the Heartroid® system. The calcification model was made of epoxy resin using the 3D printer. The model was the concentric type. Moreover, its length was 20 mm, while the lesion length was 10 mm. The diameter of the proximal, the distal and the lesion site were shown. [Color figure can be viewed at wileyonlinelibrary.com]

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  FIGURE 2. Difference of wire orbit by the guiding catheter's position. (A) Shallow guiding position. (i) Angiography of shallow guiding position. The guiding catheter was inserted shallowly. The red arrow indicates the tip of the guiding catheter. (ii) Magnified image of angiography. The red line indicates the orbit of the wire. The guide wire passed inner side. (iii) OCT images showed wire and OCT catheter existed in myocardial area. (B) Deep guiding position. (i) Angiography of deep guiding position. The guiding catheter was inserted deeply. The red arrow indicates the tip of the guiding catheter. (ii) Magnified image of angiography. The red line indicates the orbit of the wire. The guide wire passed outer line. (iii) OCT images showed wire and OCT catheter existed relatively in epicardial area compared to those of shallow guiding catheter. [Color figure can be viewed at wileyonlinelibrary.com]

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  FIGURE 3. Study flowchart. The floppy wire group included 10 lesions, the extra‐support group also 10 lesions. Low‐speed and high‐speed ablation were performed in each group. OCT = optical coherence tomography. [Color figure can be viewed at wileyonlinelibrary.com]

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  FIGURE 4. Measurement of OCT image. (A) The distance between the guidewire and the nearest vessel wall (white arrow) and the distance between the OCT catheter and the nearest vessel wall (red arrow) were shown. (B) Spatial orientation of each OCT cross‐section were categorized as myocardial, epicardial, left lateral of right lateral quadrants around the center of the lumen. The positions of the center of the guidewire and OCT catheter were assessed in each cross‐section. (C) In this image, the positions of OCT catheter and guidewire were categorized as left lateral. (D) A post OCT image. The direction of debulked area was at the epicardial quadrant. The depth of the debulked area (red arrow) and the width of the debulked area (white arrow) were shown. OCT, optical coherence tomography. [Color figure can be viewed at wileyonlinelibrary.com]

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  FIGURE 5. Flow chart of cross‐sectional evaluation of OCT after rota burr passage. After ablation, floppy low‐speed (FL group) had 41 cross‐sections, floppy high‐speed (FH group) 43 cross‐sections, support low‐speed (SL group) 43 cross‐sections, and support high‐speed (SH group) 44 cross‐sections. OCT, optical coherence tomography. [Color figure can be viewed at wileyonlinelibrary.com]

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  FIGURE 6. Comparison of the post‐OCT parameters between the four groups. The extra‐support high‐speed group demonstrated the smallest directional discrepancy among all four groups. OCT = optical coherence tomography, FL, floppy low‐speed; FH, floppy high‐speed; SL, support low‐speed; SH, support high‐speed. [Color figure can be viewed at wileyonlinelibrary.com]

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  FIGURE 7. The representative pre‐ and post‐procedural OCT images. Representative pre‐ and post‐ablation OCT images from the four experimental groups are shown. Post‐ablation OCT images in the extra‐support high‐speed (SH) group demonstrate the smallest directional discrepancy. OCT = optical coherence tomography, FL, floppy low‐speed; FH, floppy high‐speed; SL, support low‐speed; SH, support high‐speed. [Color figure can be viewed at wileyonlinelibrary.com]