Lopez David, Pollak Amy W, Meyer Craig H, Epstein Frederick H, Zhao Li, Pesch Arthur J, Jiji Ronny, Kay Jennifer R, DiMaria Joseph M, Christopher John M, Kramer Christopher M
Department of Medicine, University of Virginia Health System, Charlottesville, VA, USA.
Cardiovascular Imaging Center, University of Virginia Health System, Charlottesville, VA, USA.
J Cardiovasc Magn Reson. 2015 Feb 22;17(1):23. doi: 10.1186/s12968-015-0128-y.
Assessment of calf muscle perfusion requires a physiological challenge. Exercise and cuff-occlusion hyperemia are commonly used methods, but it has been unclear if one is superior to the other. We hypothesized that post-occlusion calf muscle perfusion (Cuff) with pulsed arterial spin labeling (PASL) cardiovascular magnetic resonance (CMR) at 3 Tesla (T) would yield greater perfusion and improved reproducibility compared to exercise hyperemia in studies of peripheral arterial disease (PAD).
Exercise and Cuff cohorts were independently recruited. PAD patients had an ankle brachial index (ABI) between 0.4-0.9. Controls (NL) had no risk factors and ABI 0.9-1.4. Subjects exercised until exhaustion (15 NL-Ex, 15 PAD-Ex) or had a thigh cuff inflated for 5 minutes (12 NL-Cuff, 11 PAD-Cuff). Peak exercise and average cuff (Cuff mean ) perfusion were compared. Six participants underwent both cuff and exercise testing. Reproducibility was tested in 8 Cuff subjects (5 NL, 3 PAD).
Controls had greater perfusion than PAD independent of stressor (NL-Ex 74 ± 21 vs. PAD-Ex 43 ± 10, p = 0.01; NL-Cuff mean 109 ± 39 vs. PAD-Cuff mean 34 ± 17 ml/min-100 g, p < 0.001). However, there was no difference between exercise and Cuff mean perfusion within groups (p > 0.6). Results were similar when the same subjects had the 2 stressors performed. Cuff mean had superior reproducibility (Cuff mean ICC 0.98 vs. Exercise ICC 0.87) and area under the receiver operating characteristic curve (Cuff mean 0.992 vs. Exercise 0.905).
Cuff hyperemia differentiates PAD patients from controls, as does exercise stress. Cuff mean and exercise calf perfusion values are similar. Cuff occlusion hyperemia has superior reproducibility and thus may be the preferred stressor.
评估小腿肌肉灌注需要进行生理刺激。运动和袖带阻断充血是常用的方法，但尚不清楚哪种方法更具优势。我们假设，在3特斯拉（T）下采用脉冲动脉自旋标记（PASL）心血管磁共振（CMR）进行袖带阻断后小腿肌肉灌注（袖带法），与运动充血相比，在周围动脉疾病（PAD）研究中能产生更高的灌注并提高可重复性。
独立招募运动组和袖带法组。PAD患者的踝臂指数（ABI）在0.4 - 0.9之间。对照组（NL）无危险因素，ABI为0.9 - 1.4。受试者运动至 exhaustion（15名NL - Ex，15名PAD - Ex）或大腿袖带充气5分钟（12名NL - Cuff，11名PAD - Cuff）。比较运动峰值和袖带平均灌注。6名参与者同时接受了袖带法和运动测试。在8名袖带法受试者（5名NL，3名PAD）中测试了可重复性。
无论刺激因素如何，对照组的灌注均高于PAD组（NL - Ex 74 ± 21 vs. PAD - Ex 43 ± 10，p = 0.01；NL - Cuff平均 109 ± 39 vs. PAD - Cuff平均 34 ± 17 ml/min - 100 g，p < 0.001）。然而，组内运动和袖带平均灌注之间无差异（p > 0.6）。当同一受试者接受两种刺激时，结果相似。袖带平均具有更好的可重复性（袖带平均组内相关系数ICC 0.98 vs. 运动组ICC 0.87）以及受试者工作特征曲线下面积（袖带平均 0.992 vs. 运动 0.905）。
袖带充血与运动应激一样，可区分PAD患者与对照组。袖带平均和运动小腿灌注值相似。袖带阻断充血具有更好的可重复性，因此可能是首选的刺激因素。
