Department of Vascular Medicine, University Medical Center Utrecht, The Netherlands.
Int J Cardiol. 2013 Aug 10;167(3):883-8. doi: 10.1016/j.ijcard.2012.01.091. Epub 2012 Mar 3.
A myocardial bridge (MB) is a band of myocardium covering a coronary artery segment, typically located in the left anterior descending coronary artery (LAD). Bridged segments of the coronary artery are isolated from the influence of perivascular adipose tissue. The aims of this study were to investigate the relationship between MBs and atherosclerosis in bridged LAD segments and to evaluate whether perivascular adipose tissue is involved in this relationship.
MBs were identified in the coronary arteries of patients referred for diagnostic cardiac CT. The calcium score of MBs of the LAD or, in patients without LAD-MBs, of a corresponding LAD segment at the same distance from its origin and over the same length was measured.
Of 128 patients, 56 (44%) had in total 73 MBs. The mean MB length was 22 ± 14 mm and the median MB thickness was 0.8mm (interquartile range 0.3-2.1mm). MBs in the LAD were present in 40 patients (31%). The calcium score was 0 in 95% of the LAD segments with MBs compared with 52% of the corresponding LAD segments without MBs. The association between LAD-MBs and calcium score (OR 0.06, 95% CI 0.01-0.25) was not influenced by age and gender, but was attenuated by local perivascular adipose tissue thickness (OR 0.35, 95% CI 0.04-2.70).
Coronary artery segments covered with an MB have a lower calcium score than segments without an MB. The association between MBs and calcium scores was influenced by local perivascular adipose tissue thickness.
心肌桥（MB）是覆盖冠状动脉节段的心肌带，通常位于左前降支冠状动脉（LAD）。桥接的冠状动脉段与血管周围脂肪组织的影响隔离开来。本研究的目的是研究 MB 与桥接 LAD 段的动脉粥样硬化之间的关系，并评估血管周围脂肪组织是否参与这种关系。
在接受诊断性心脏 CT 检查的患者的冠状动脉中识别 MB。测量 LAD 的 MB 的钙评分，或者在没有 LAD-MB 的患者中，从其起源处相同距离和相同长度处的相应 LAD 段的钙评分。
在 128 名患者中，共有 73 个 MB（56 例，44%）。MB 的平均长度为 22±14mm，中位数 MB 厚度为 0.8mm（四分位间距 0.3-2.1mm）。LAD 中有 40 例（31%）存在 MB。与无 MB 的相应 LAD 段相比，有 MB 的 LAD 段的钙评分 0 占 95%，而无 MB 的相应 LAD 段占 52%。LAD-MB 与钙评分之间的关联（OR 0.06，95%CI 0.01-0.25）不受年龄和性别影响，但受局部血管周围脂肪组织厚度影响（OR 0.35，95%CI 0.04-2.70）。
覆盖 MB 的冠状动脉段的钙评分低于无 MB 的段。MB 与钙评分之间的关联受局部血管周围脂肪组织厚度的影响。
