G Toth Gabor, Haude Michael, Lootz Daniel, Pellicano Mariano, Wijns William
University Heart Centre Graz, Medical University of Graz, Austria; Cardiovascular Research Centre Aalst, OLV-Clinic Aalst, Belgium.
Medical Clinic I, Städtische Kliniken Neuss, Lukaskrankenhaus GmbH, Germany.
Cardiovasc Revasc Med. 2019 Oct;20(10):858-864. doi: 10.1016/j.carrev.2018.11.023. Epub 2018 Dec 5.
The aim of this work is to evaluate in an in vitro setting the behavior of resorbable magnesium scaffolds (RMS) in bifurcations.
As coronary bifurcations represent an important portion of all PCIs, it is crucial to understand whether RMS is applicable in these complex lesions.
Performance of RMS was evaluated with focus on bifurcations. In bifurcations RMS was tested for (1) main branch stenting with side branch opening and proximal optimization; for (2) main branch stenting with final kissing and proximal optimization; for (3) T-and-protrusion technique; for (4) string technique, which is a minimalistic version of conventional culotte technique. All tests were performed using 3.50 × 25 mm RMS. Results were evaluated by fluoroscopy, optical coherence tomography (OCT) and micro-computed tomography (μCT), for scaffold conformability, strut apposition, structural deformation and strut fracture.
All planned procedural steps were performed successfully with good result according to fluoroscopy. By OCT the overall malapposition rate in bifurcation cases was 4.3%, occurring predominantly in the carinal area. No malapposition was seen at the proximal main branch confirming proper conformability of RMS. μCT analysis has shown that final kissing dilation resulted in fully stretched struts in cases, where performed with 3.5 and 3.0 mm balloons. In one case a broken connector (T-and-protrusion) and in another case, a broken strut (String technique) were identified.
RMS can structurally cope with bifurcations. Still, for cases and techniques where overexpansion beyond the recommended limit is needed, RMS might not be the proper device due to risk of strut fracture.
本研究旨在体外评估可吸收镁支架（RMS）在分叉病变中的性能。
由于冠状动脉分叉病变占所有经皮冠状动脉介入治疗（PCI）的重要部分，了解RMS是否适用于这些复杂病变至关重要。
重点评估RMS在分叉病变中的性能。在分叉病变中，对RMS进行以下测试：（1）主支支架置入并保持边支开放及近端优化；（2）主支支架置入并进行最终球囊对吻扩张及近端优化；（3）T形和突出技术；（4）串技术，即传统裤裙式技术的简化版。所有测试均使用3.50×25 mm的RMS进行。通过荧光透视、光学相干断层扫描（OCT）和微计算机断层扫描（μCT）评估支架的贴合性、支柱贴壁情况、结构变形和支柱断裂情况。
根据荧光透视，所有计划的手术步骤均成功完成，效果良好。通过OCT检查，分叉病变病例的总体贴壁不良率为4.3%，主要发生在嵴部区域。在主支近端未见贴壁不良，证实RMS具有良好的贴合性。μCT分析表明，在使用3.5和3.0 mm球囊进行最终球囊对吻扩张的病例中，支柱完全伸展。在1例中发现连接器断裂（T形和突出技术），在另1例中发现支柱断裂（串技术）。
RMS在结构上能够应对分叉病变。然而，对于需要超过推荐限度进行过度扩张的病例和技术，由于存在支柱断裂的风险，RMS可能不是合适的器械。
