Department of Cardiology, Liuhuaqiao Hospital, 111# Liuhua Road, Guangzhou 510010, China.
J Nucl Cardiol. 2011 Apr;18(2):314-23. doi: 10.1007/s12350-011-9342-7. Epub 2011 Feb 17.
Reverse redistribution (RR) is one of the features on myocardial perfusion scintigraphy (MPS) in patients with coronary artery spasm (CAS). This study was aimed to explore the mechanism of RR in patients with suspicion for CAS.
Thirty patients with RR and suspicion for CAS but without coronary artery stenosis (RR group) and 32 control patients without RR (control group) underwent coronary angiography before and after a dipyridamole administration. Coronary blood flow velocity and myocardial perfusion, as determined by corrected thrombolysis in myocardial infarction (TIMI) frame count (CTFC) and TIMI myocardial perfusion grade (TMPG), were measured. Coronary angiography showed significantly slower blood flow velocity [CTFC (37 ± 6) frame vs (29 ± 7) frame, P < .01] and lower myocardial perfusion [TMPG (2.08 ± 0.38) grade vs (2.55 ± 0.33) grade, P < .05] in RR-related arteries than in RR-unrelated arteries in the RR group. But, there was no significant difference among different coronary artery branches in the control group. After the injection of dipyridamole, CTFC decreased and TMPG increased in the RR group. The decline in CTFC and the increase in TMPG in RR-related arteries were more significant than those in RR-unrelated ones (28% vs 14% and 45% vs 16%, respectively; both P < .01). The endothelin-1/nitric oxide (NO) ratio was significantly higher in the RR group than in the control group before the injection of dipyridamole (2.79 ± 0.37 vs 1.70 ± 0.19, P < .01). After the injection of dipyridamole, the ratio went down in both groups, but the decline was statistically significant in the RR group (2.42 ± 0.33, P < .05) but not in the control group (1.42 ± 0.19, P < .05). Pearson correlation analysis showed that there was a positive correlation between summed rest scores on MPS and the endothelin-1/NO ratio (r = 0.853, P = .000) as well as CTFC (r = 0.808, P = .000) before the injection of dipyridamole in the RR group.
Patients with suspicion for CAS may exhibit a mild spasm of RR-related arteries and corresponding microvasculature and a significant imbalance of coronary blood flow velocity and myocardial perfusion at rest between RR-related and RR-unrelated areas. This is overcome by stress-induced hyperemic flow increases and which may account for RR on MPS.
在冠状动脉痉挛（CAS）患者的心肌灌注闪烁显像（MPS）中，反向再分布（RR）是其特征之一。本研究旨在探讨 RR 患者的 CAS 发病机制。
30 例 RR 合并 CAS 但无冠状动脉狭窄患者（RR 组）和 32 例无 RR 的对照患者（对照组）在双嘧达莫注射前后接受冠状动脉造影。校正的心肌梗死溶栓治疗帧数计数（CTFC）和 TIMI 心肌灌注分级（TMPG）测量冠状动脉血流速度和心肌灌注。RR 组 RR 相关动脉的血流速度[CTFC（37±6）帧比（29±7）帧，P<0.01]和心肌灌注[TMPG（2.08±0.38）级比（2.55±0.33）级，P<0.05]明显低于 RR 非相关动脉。但对照组不同冠状动脉分支之间无显著差异。双嘧达莫注射后，RR 组 CTFC 降低，TMPG 增加。RR 相关动脉 CTFC 下降和 TMPG 增加幅度大于 RR 非相关动脉（分别为 28%比 14%和 45%比 16%；均 P<0.01）。双嘧达莫注射前，RR 组内皮素-1/一氧化氮（NO）比值明显高于对照组（2.79±0.37比 1.70±0.19，P<0.01）。双嘧达莫注射后，两组比值均下降，但 RR 组下降有统计学意义（2.42±0.33，P<0.05），对照组无统计学意义（1.42±0.19，P<0.05）。Pearson 相关分析显示，RR 组 MPS 静息总和评分与内皮素-1/NO 比值（r=0.853，P=0.000）和 CTFC（r=0.808，P=0.000）呈正相关。
怀疑有 CAS 的患者可能在 RR 相关动脉及其相应的微血管中存在轻度痉挛，并且在 RR 相关区域和 RR 非相关区域之间存在静息时冠状动脉血流速度和心肌灌注的显著不平衡。这在应激诱导的充血性血流增加时得到克服，这可能是 MPS 上出现 RR 的原因。
