Amano Hideo, Ikeda Takanori, Toda Mikihito, Okubo Ryo, Yabe Takayuki, Watanabe Ippei, Saito Daiga
Department of Cardiovascular Medicine, Toho University Faculty of Medicine.
Int Heart J. 2016 May 25;57(3):285-91. doi: 10.1536/ihj.15-373. Epub 2016 May 9.
It has been reported that coronary vasa vasorum is associated with plaque vulnerability, and low-echoic structures in grayscale intravascular ultrasound (IVUS) are consistent pathologically with vasa vasorum. However, the association of low-echoic structures with plaque composition and no-reflow phenomenon during percutaneous coronary intervention (PCI) is unclear. We investigated plaque composition in virtual histology IVUS (VH-IVUS) and no-reflow phenomenon during PCI of low-echoic structures.A total of 106 lesions being treated by VH-IVUS before PCI were included in this study. Low-echoic structure was defined as a small tubular structure exterior to media without a connection to the vessel lumen in ≥ 3 consecutive crosssectional IVUS images. Lesions with low-echoic structures were found in 42% (45/106).Lesions with low-echoic structures were more prevalent in acute coronary syndrome (ACS) patients (53% [24/45] versus 20% [12/61], P < 0.001), had more positive remodeling (49% [22/45] versus 21% [13/61], P = 0.003), a larger number of VH-IVUS derived thin-cap fibroatheromas (VH-TCFAs) (0.64 ± 0.53 versus 0.05 ± 0.22, P < 0.001), more VH-TCFAs with a baseline plaque burden of 70% or more and minimal luminal area of 4.0 mm(2) or less (29% [13/45] versus 2% [1/61], P < 0.001), and more frequent no-reflow phenomenon after stent implantation and more final TIMI flow grade 0/1/2 (38% [17/45] versus 5% [3/61], P < 0.001; 9% [4/45] versus 0% [0/61], P = 0.03) than lesions without low-echo structures.Lesions with low-echoic structures in grayscale IVUS had high plaque vulnerability and were more prevalent in ACS patients, positive remolding, and VH-TCFAs, and they had more frequent no-reflow phenomenon during PCI than lesions without low-echoic structures.
据报道，冠状动脉血管滋养管与斑块易损性相关，而灰阶血管内超声（IVUS）中的低回声结构在病理上与血管滋养管一致。然而，低回声结构与斑块成分以及经皮冠状动脉介入治疗（PCI）期间无复流现象之间的关联尚不清楚。我们研究了虚拟组织学IVUS（VH-IVUS）中的斑块成分以及低回声结构PCI期间的无复流现象。
本研究纳入了106个在PCI前接受VH-IVUS检查的病变。低回声结构定义为在连续≥3个IVUS横截面图像中，位于中膜外部且与血管腔无连接的小管状结构。42%（45/106）的病变发现有低回声结构。
有低回声结构的病变在急性冠状动脉综合征（ACS）患者中更为常见（53% [24/45] 对20% [12/61]，P < 0.001），有更多的正向重构（49% [22/45] 对21% [13/61]，P = 0.003），VH-IVUS衍生的薄帽纤维粥样斑块（VH-TCFAs）数量更多（0.64 ± 0.53对0.05 ± 0.22，P < 0.001），更多基线斑块负荷≥70%且最小管腔面积≤4.0 mm²的VH-TCFAs（29% [13/45] 对2% [1/61]，P < 0.001），并且支架植入后无复流现象更频繁，最终TIMI血流分级为0/1/2的情况也更多（38% [17/45] 对5% [3/61]，P < 0.001；9% [4/45] 对0% [0/61]，P = 0.03），比无低回声结构的病变更多。
灰阶IVUS中有低回声结构的病变具有较高的斑块易损性，在ACS患者、正向重构和VH-TCFAs中更为常见，并且在PCI期间比无低回声结构的病变有更频繁的无复流现象。
