Kattapuram Nathan, Shadman Shahrad, Morgan Eric E, Benton Charles, Awojoodu Stacian, Kim Dong-Yun, Ramos Joao, Barac Ana, Bandettini W Patricia, Kellman Peter, Weissman Gaby, Carlsson Marcus
Division of Intramural Research, National Heart, Lung and Blood Institute, Bethesda, MD, USA.
Inova Schar Heart and Vascular, Falls Church, VA, USA.
medRxiv. 2024 Jan 16:2024.01.15.23300449. doi: 10.1101/2024.01.15.23300449.
Regadenoson is used to induce hyperemia in cardiac imaging, facilitating diagnosis of ischemia and assessment of coronary flow reserve (CFR). While the regadenoson package insert recommends administration of radionuclide tracer 10-20 seconds after injection, peak hyperemia has been observed at approximately 100 seconds after injection in healthy volunteers undergoing cardiovascular magnetic resonance imaging (CMR). It is unclear when peak hyperemia occurs in a patient population.
The goal of this study was to determine time to peak hyperemia after regadenoson injection in healthy volunteers and patients, and whether the recommended image timing in the package insert underestimates CFR.
Healthy volunteers (n=15) and patients (n=25) underwent stress CMR, including phase-contrast imaging of the coronary sinus at rest and multiple timepoints after 0.4 mg regadenoson injection. Coronary sinus flow (ml/min) was divided by resting values to yield CFR. Smoothed, time-resolved curves for CFR were generated with pointwise 95% confidence intervals.
CFR between 60 and 120 seconds was significantly higher than CFR at 30 seconds after regadenoson injection (p < 0.05) as shown by non-overlapping 95% confidence intervals for both healthy volunteers (30 s, [2.8, 3.4]; 60 s, [3.8, 4.4]; 90 s, [4.1, 4.7]; 120 s, [3.6, 4.3]) and patients (30 s, [2.1, 2.5]; 60 s, [2.6, 3.1]; 90 s, [2.7, 3.2]; 120 s, [2.5, 3.1]).
Imaging at 90 seconds following regadenoson injection is the optimal approach to capture peak hyperemia. Imaging at 30 seconds, which is more aligned with the package insert recommendation, would yield an underestimate of CFR and confound assessment of microvascular dysfunction.
雷加昔布用于心脏成像中诱导充血，有助于缺血的诊断和冠状动脉血流储备（CFR）的评估。虽然雷加昔布包装说明书建议在注射后10 - 20秒给予放射性核素示踪剂，但在接受心血管磁共振成像（CMR）的健康志愿者中，在注射后约100秒观察到充血峰值。尚不清楚在患者群体中充血峰值何时出现。
本研究的目的是确定健康志愿者和患者注射雷加昔布后达到充血峰值的时间，以及包装说明书中推荐的成像时间是否低估了CFR。
健康志愿者（n = 15）和患者（n = 25）接受负荷CMR检查，包括静息时和注射0.4mg雷加昔布后多个时间点的冠状静脉窦相位对比成像。冠状静脉窦血流量（ml/分钟）除以静息值以得出CFR。生成具有逐点95%置信区间的CFR平滑时间分辨曲线。
如健康志愿者（30秒，[2.8, 3.4]；60秒，[3.8, 4.4]；90秒，[4.1, 4.7]；120秒，[3.6, 4.3]）和患者（30秒，[2.1, 2.5]；60秒，[2.6, 3.1]；90秒，[2.7, 3.2]；120秒，[2.5, 3.1]）的不重叠95%置信区间所示，雷加昔布注射后60至120秒的CFR显著高于30秒时的CFR（p < 0.05）。
注射雷加昔布后90秒成像为捕捉充血峰值的最佳方法。与包装说明书建议更一致的30秒成像会低估CFR并混淆微血管功能障碍的评估。
