UCAIR, Department of Radiology, University of Utah, Salt Lake City, UT, USA.
Int J Cardiovasc Imaging. 2012 Aug;28(6):1435-44. doi: 10.1007/s10554-011-9949-4. Epub 2011 Oct 4.
The A2(A) receptor agonist, regadenoson, is increasingly used as a vasodilator during nuclear myocardial perfusion imaging. Regadenoson is administered as a single, fixed dose. Given the frequency of obesity in patients with symptoms of heart disease, it is important to know whether the fixed dose of regadenoson produces maximal coronary hyperemia in subjects of widely varying body size. Thirty subjects (12 female, 18 male, mean BMI 30.3 ± 6.5, range 19.6-46.6) were imaged on a 3T magnetic resonance scanner. Imaging with a saturation recovery radial turboFLASH sequence was done first at rest, then during adenosine infusion (140 μg/kg/min) and 30 min later with regadenoson (0.4 mg/5 ml bolus). A 5 cc/s injection of Gd-BOPTA was used for each perfusion sequence, with doses of 0.02, 0.03 and 0.03 mmol/kg, respectively. Analysis of the upslope of myocardial time-intensity curves and quantitative processing to obtain myocardial perfusion reserve (MPR) values were performed for each vasodilator. The tissue upslopes for adenosine and regadenoson matched closely (y = 1.1x + 0.03, r = 0.9). Mean MPR was 2.3 ± 0.6 for adenosine and 2.4 ± 0.9 for regadenoson (p = 0.14). There was good agreement between MPR measured with adenosine and regadenoson (y = 1.1x - 0.06, r = 0.7). The MPR values measured with both agents tended to be lower as BMI increased. There were no complications during administration of either agent. Regadenoson produced fewer side effects. Fixed dose regadenoson and weight adjusted adenosine produce similar measures of MPR in patients with a wide range of body sizes. Regadenoson is a potentially useful vasodilator for stress MRI studies.
阿 2(A) 受体激动剂雷卡地诺松在核心肌灌注成像中越来越多地被用作血管扩张剂。雷卡地诺松作为单一的固定剂量给药。鉴于心脏病症状患者中肥胖的频率，了解雷卡地诺松的固定剂量是否会在体型差异很大的受试者中产生最大的冠状动脉充血是很重要的。30 名受试者（12 名女性，18 名男性，平均 BMI 为 30.3 ± 6.5，范围 19.6-46.6）在 3T 磁共振扫描仪上进行成像。使用饱和恢复径向涡轮 FLASH 序列首先在休息时进行成像，然后在腺苷输注（140μg/kg/min）期间进行成像，30 分钟后用雷卡地诺松（0.4mg/5ml 推注）进行成像。每个灌注序列使用 5cc/s 的 Gd-BOPTA 注射，剂量分别为 0.02、0.03 和 0.03mmol/kg。分别对每个血管扩张剂的心肌时间-强度曲线的斜率进行分析和定量处理，以获得心肌灌注储备（MPR）值。腺苷和雷卡地诺松的组织斜率匹配得很好（y=1.1x+0.03，r=0.9）。腺苷的平均 MPR 为 2.3±0.6，雷卡地诺松为 2.4±0.9（p=0.14）。用腺苷和雷卡地诺松测量的 MPR 之间有很好的一致性（y=1.1x-0.06，r=0.7）。两种药物的 MPR 值随着 BMI 的增加而趋于降低。两种药物给药期间均无并发症。雷卡地诺松的副作用较少。在体型差异很大的患者中，固定剂量的雷卡地诺松和体重调整的腺苷产生相似的 MPR 测量值。雷卡地诺松是应激 MRI 研究中一种有潜力的有用的血管扩张剂。
