Department of Cardiovascular Medicine, Tokushima Red Cross Hospital, 103 Irinoguchi, Komatsushima-cho, Komatsushima, Tokushima, 773-8502, Japan.
Yale University School of Medicine, New Haven, USA.
Int J Cardiovasc Imaging. 2021 Mar;37(3):775-782. doi: 10.1007/s10554-020-02075-1. Epub 2020 Oct 20.
Successful recanalization of coronary chronic total occlusion (CTO) can induce subsequent positive vascular remodeling. Although myocardial bridge (MB) is known to alter endothelial function and wall shear stress, the impact of MB on late lumen enlargement in the distal segment is unclear. A total of 59 patients who underwent successful percutaneous coronary intervention (PCI) for CTO in the left anterior descending artery (LAD) under intravascular ultrasound (IVUS) guidance and follow-up angiography at 8-12 months were included. Gray-scale IVUS images were analyzed and MB was detected. Lumen diameter (LD) at distal reference at post-PCI was quantitatively compared with corresponding LD at follow-up coronary angiography to assess late lumen enlargement. MB on IVUS was detected in 17 patients (29%). The length from LAD ostium to the entry of CTO was shorter (11.7 ± 13.9 vs. 22.8 ± 13.4 mm, p = 0.006) and LD at distal reference at post-PCI was smaller (1.65 ± 0.54 vs. 1.97 ± 0.56 mm, p = 0.049) in patients with MB than those without. At the mean follow-up of 10.4 ± 2.4 months, LD at distal reference was significantly increased by 25% from baseline to follow-up in the overall population (1.88 ± 0.57 vs. 2.21 ± 0.41 mm, p < 0.001), with a greater increase in patients with MB compared to those without (46 ± 31% vs. 17 ± 29%, p < 0.001). Multivariable analysis indicated MB as an independent predictor of late lumen enlargement. In patients with MB on IVUS, CTO was located in more proximal segment of LAD than those without. Late lumen enlargement at follow-up was greater in patients with MB compared to the counterpart.
成功开通冠状动脉慢性完全闭塞（CTO）可诱导后续的血管正性重构。尽管已知心肌桥（MB）会改变内皮功能和壁面切应力，但 MB 对远端节段晚期管腔扩大的影响尚不清楚。共纳入 59 例在血管内超声（IVUS）引导下成功接受经皮冠状动脉介入治疗（PCI）的左前降支（LAD）CTO 患者，在 8-12 个月时进行了随访血管造影。分析灰阶 IVUS 图像并检测 MB。比较 PCI 后远端参考处的管腔直径（LD）与随访冠状动脉造影时的相应 LD，以评估晚期管腔扩大。17 例患者（29%）在 IVUS 上检测到 MB。LAD 开口至 CTO 入口的距离较短（11.7±13.9 比 22.8±13.4mm，p=0.006），且 MB 患者 PCI 后远端参考处的 LD 较小（1.65±0.54 比 1.97±0.56mm，p=0.049）。在平均 10.4±2.4 个月的随访中，整体人群的远端参考 LD 从基线到随访时显著增加了 25%（1.88±0.57 比 2.21±0.41mm，p<0.001），且 MB 患者的增加幅度大于无 MB 患者（46±31%比 17±29%，p<0.001）。多变量分析表明 MB 是晚期管腔扩大的独立预测因素。在 IVUS 上有 MB 的患者中，CTO 位于 LAD 的更近端节段。与无 MB 患者相比，MB 患者的随访晚期管腔扩大更大。
