Department of Cardiology, Robert Bosch Medical Center, Auerbachstraße 110, 70376, Stuttgart, Germany.
Department of Cardiology and Angiology, University Hospital Tübingen, Tübingen, Germany.
J Cardiovasc Magn Reson. 2019 Jun 24;21(1):33. doi: 10.1186/s12968-019-0542-7.
Adenosine is used in stress perfusion cardiac imaging to reveal myocardial ischemia by its vasodilator effects. Caffeine is a competitive antagonist of adenosine. However, previous studies reported inconsistent results about the influence of caffeine on adenosine's vasodilator effect. This study assessed the impact of caffeine on the myocardial perfusion reserve index (MPRI) using adenosine stress cardiovascular magnetic resonance imaging (CMR). Moreover, we sought to evaluate if the splenic switch-off sign might be indicative of prior caffeine consumption.
Semiquantitative perfusion analysis was performed in 25 patients who underwent: 1) caffeine-naïve adenosine stress CMR demonstrating myocardial ischemia and, 2) repeat adenosine stress CMR after intake of caffeine. MPRI (global; remote and ischemic segments), and splenic perfusion ratio (SPR) were assessed and compared between both exams.
Global MPRI after caffeine was lower vs. caffeine-naïve conditions (1.09 ± 0.19 vs. 1.24 ± 0.19; p < 0.01). MPRI in remote myocardium decreased by caffeine (1.24 ± 0.19 vs. 1.49 ± 0.19; p < 0.001) whereas MPRI in ischemic segments (0.89 ± 0.18 vs. 0.95 ± 0.23; p = 0.23) was similar, resulting in a lower MPRI ratio (=remote/ischemic segments) after caffeine consumption vs. caffeine-naïve conditions (1.41 ± 0.19 vs. 1.64 ± 0.35, p = 0.01). The SPR was unaffected by caffeine (SPR 0.38 ± 0.19 vs. 0.38 ± 0.18; p = 0.92).
Caffeine consumption prior to adenosine stress CMR results in a lower global MPRI, which is driven by the decreased MPRI in remote myocardium and underlines the need of abstinence from caffeine. The splenic switch-off sign is not affected by prior caffeine intake.
腺苷通过其血管扩张作用用于应激灌注心脏成像以显示心肌缺血。咖啡因是腺苷的竞争性拮抗剂。然而，先前的研究报告了咖啡因对腺苷血管扩张作用的影响不一致的结果。本研究使用腺苷应激心血管磁共振成像（CMR）评估了咖啡因对心肌灌注储备指数（MPRI）的影响。此外，我们试图评估脾脏关闭征是否可以指示先前的咖啡因消耗。
对 25 例接受以下检查的患者进行半定量灌注分析：1）咖啡因-naïve 腺苷应激 CMR 显示心肌缺血，以及 2）摄入咖啡因后重复腺苷应激 CMR。评估并比较两次检查之间的 MPRI（整体；远程和缺血节段）和脾灌注比（SPR）。
与咖啡因-naïve 条件相比，咖啡因后整体 MPRI 降低（1.09±0.19 比 1.24±0.19；p<0.01）。MPRI 在远程心肌中因咖啡因而降低（1.24±0.19 比 1.49±0.19；p<0.001），而缺血节段的 MPRI（0.89±0.18 比 0.95±0.23；p=0.23）相似，因此，与咖啡因-naïve 条件相比，咖啡因消耗后 MPRI 比值（=远程/缺血节段）降低（1.41±0.19 比 1.64±0.35，p=0.01）。SPR 不受咖啡因影响（SPR 0.38±0.19 比 0.38±0.18；p=0.92）。
在腺苷应激 CMR 之前摄入咖啡因会导致整体 MPRI 降低，这是由远程心肌中 MPRI 的降低驱动的，这强调了需要戒除咖啡因。脾脏关闭征不受先前咖啡因摄入的影响。
