Department of Radiology, The Third Hospital of Hebei Medical University, Shijiazhuang, Hebei Province, China.
Department of Medical Imaging, The Second Hospital of Hebei Medical University, Shijiazhuang, Hebei Province, China.
Clin Physiol Funct Imaging. 2024 May;44(3):251-259. doi: 10.1111/cpf.12872. Epub 2024 Feb 14.
To quantitatively investigate the effect of myocardial bridge (MB) in the left anterior descending artery (LAD) on the fractional flow reserve (FFR).
Three-hundred patients with LAD MB who had undergone coronary artery CT angiography (CCTA) were retrospectively enroled, and 104 normal patients were enroled as the control. The CCTA-derived fractional flow reserve (FFRCT) was measured at the LAD 10 mm proximal (FFR1) and 20-40 mm distal (FFR3) to the MB and at the MB location (FFR2).
FFR2 and FFR3 of the MB (with BM only) and MBLA (with both MB and atherosclerosis) groups were significantly (p < 0.01) lower than those of the control. The FFR3 distal to the MB was significantly lower (p < 0.01) than that of the control. The FFRCT of the whole LAD in the MBLA group was significantly (p < 0.05) lower than that of the MB and control group (p < 0.05). MB length (OR 1.061) and MB muscle index (odds ratio or OR 1.007) were two risk factors for abnormal FFRCT, and MB length was a significant independent risk factor for abnormal FFRCT (OR = 1.077). LAD stenosis degree was a risk factor for abnormal FFRCT values (OR 3.301, 95% confidence interval [CI] 1.441-7.562, p = 0.005) and was also a significant independent risk factor (OR = 3.369, 95% CI: 1.392-8.152; p = 0.007) for abnormal FFRCT.
MB significantly affects the FFRCT of distal coronary artery. For patients with MB without atherosclerosis, the MB length is a risk factor significantly affecting FFRCT, and for patients with MB accompanied by atherosclerosis, LAD stenotic severity is an independent risk factor for FFRCT.
定量研究左前降支（LAD）中的心肌桥（MB）对血流储备分数（FFR）的影响。
回顾性纳入 300 例接受冠状动脉 CT 血管造影（CCTA）检查的 LAD MB 患者，并纳入 104 例正常患者作为对照。在 MB 近端 10mm（FFR1）和 20-40mm 处（FFR3）及 MB 处（FFR2）测量 CCTA 衍生的 FFR（FFRCT）。
MB（仅存在 BM）和 MBLA（同时存在 MB 和动脉粥样硬化）组的 FFR2 和 FFR3 明显（p < 0.01）低于对照组。MB 远端的 FFR3 明显低于对照组（p < 0.01）。MBLA 组的整个 LAD 的 FFRCT 明显（p < 0.05）低于 MB 组和对照组（p < 0.05）。MB 长度（OR 1.061）和 MB 肌肉指数（比值比或 OR 1.007）是 FFRCT 异常的两个危险因素，MB 长度是 FFRCT 异常的显著独立危险因素（OR = 1.077）。LAD 狭窄程度是 FFRCT 值异常的危险因素（OR 3.301，95%置信区间 [CI] 1.441-7.562，p = 0.005），也是 FFRCT 异常的显著独立危险因素（OR = 3.369，95%CI：1.392-8.152；p = 0.007）。
MB 显著影响远端冠状动脉的 FFRCT。对于无动脉粥样硬化的 MB 患者，MB 长度是显著影响 FFRCT 的危险因素，对于伴有动脉粥样硬化的 MB 患者，LAD 狭窄程度是 FFRCT 的独立危险因素。
