Cardiovascular Institute, Tianjin Chest Hospital, Tianjin 300222, China.
Graduate School of Medicine, Tianjin Medical University, Tianjin 300070, China.
Chin Med J (Engl). 2019 Apr 20;132(8):957-962. doi: 10.1097/CM9.0000000000000183.
Saphenous vein grafts disease (SVGD) is a common complication after coronary artery bypass graft (CABG) and normally treated by percutaneous coronary intervention (PCI). The most common complication after SVG-PCI is slow or no-reflow. It is known that the no-reflow phenomenon occurs in up to 15% of the SVG-PCI and is associated with high risk of major adverse cardiac events (MACEs) and mortality, therefore, it is important to investigate the factors that could predict the clinical outcome of PCI for risk stratification and guiding interventions. In recent years, the spectral analysis of intravascular ultrasound (IVUS) radiofrequency data (virtual histology-IVUS [VH-IVUS]) has been used to provide quantitative assessment on both plaque compositions and morphologic characteristics.
The PubMed, Embase, and Central databases were searched for possible relevant studies published from 1997 to 2018 using the following index keywords: "Coronary artery bypass grafting," "Saphenous venous graft disease," "Virtual histology-intravascular ultrasound," "Virtual histology-intravascular ultrasound," and "Percutaneous coronary intervention."
The primary references were Chinese and English articles including original studies and literature reviews, were identified and reviewed to summarize the advances in the application of VH-IVUS techniques in situ vascular and venous graft vascular lesions.
With different plaque components exhibiting a defined spectrum, VH-IVUS can classify atherosclerotic plaque into four types: fibrous tissue (FT), fibro fatty (FF), necrotic core (NC), and dense calcium (DC). The radiofrequency signal is mathematically transformed into a color-coded representation, including lipid, fibrous tissue, calcification, and necrotic core. Several studies have demonstrated the independent relationship between VH-IVUS-defined plaque classification or plaque composition and MACEs, but a significant association between plaque components and no-reflow after PCI in acute coronary syndrome. In recent years, VH-IVUS are applied to assess the plaque composition of SVGD, based on the similarity of pathophysiological mechanisms between coronary artery disease (CAD) and SVGD, further studies with the larger sample size, the long-term follow-up, multicenter clinical trials may be warranted to investigate the relationship between plaque composition of saphenous vein graft (SVG) by VH-IVUS and clinical outcomes in patients with SVGD undergoing PCI.
In degenerative SVG lesions, VH-IVUS found that plaque composition was associated with clinical features, future studies need to explore the relationship between VH-IVUS defined atherosclerotic plaque components and clinical outcomes in SVGD patients undergoing PCI, an innovative prediction tool of clinical outcomes can be created.
冠状动脉旁路移植术后（CABG）常发生大隐静脉移植物病变（SVGD），通常采用经皮冠状动脉介入治疗（PCI）治疗。SVG-PCI 后最常见的并发症是慢血流或无复流。已知 SVG-PCI 后无复流现象的发生率高达 15%，且与主要不良心脏事件（MACEs）和死亡率的高风险相关，因此，有必要研究可预测 PCI 临床结果的因素，以便进行风险分层和指导干预。近年来，血管内超声（IVUS）射频数据的光谱分析（虚拟组织学-IVUS [VH-IVUS]）已用于提供斑块成分和形态特征的定量评估。
使用以下索引关键词在 1997 年至 2018 年期间在 PubMed、Embase 和中央数据库中搜索可能的相关研究：“冠状动脉旁路移植术”、“大隐静脉移植物病变”、“虚拟组织学-血管内超声”、“虚拟组织学-血管内超声”和“经皮冠状动脉介入治疗”。
确定并回顾了主要参考文献，包括原始研究和文献综述，以总结 VH-IVUS 技术在原位血管和静脉移植物血管病变中的应用进展。
由于不同的斑块成分表现出特定的光谱，VH-IVUS 可将动脉粥样硬化斑块分为四种类型：纤维组织（FT）、纤维脂肪（FF）、坏死核心（NC）和致密钙（DC）。射频信号经数学转换为彩色编码表示，包括脂质、纤维组织、钙化和坏死核心。几项研究表明，VH-IVUS 定义的斑块分类或斑块成分与 MACEs 之间存在独立关系，但在急性冠状动脉综合征中与 PCI 后无复流之间存在显著关联。近年来，基于冠心病（CAD）和 SVGD 之间病理生理机制的相似性，VH-IVUS 已应用于评估 SVGD 中的斑块成分，进一步的研究可能需要更大的样本量、长期随访、多中心临床试验来研究 SVGD 患者 SVG 中的 VH-IVUS 斑块成分与 PCI 后临床结局之间的关系。
在退行性 SVGD 病变中，VH-IVUS 发现斑块成分与临床特征相关，未来需要研究 VH-IVUS 定义的动脉粥样硬化斑块成分与 SVGD 患者 PCI 后临床结局之间的关系，创建一种新的临床结局预测工具。
