Radiology Department, Plymouth Hospitals NHS Trust, Plymouth, Devon PL6 8DH, UK.
Cardiology Department, Musgrove Park Hospital, Taunton, Somerset TA1 5DA, UK.
Clin Radiol. 2014 Jul;69(7):739-44. doi: 10.1016/j.crad.2014.03.003. Epub 2014 May 10.
To evaluate the usage, safety, and efficacy of high-dose intravenous metoprolol for heart rate reduction in computer tomographic (CT) coronary angiography.
As this was retrospective analysis of anonymous data, medical ethics committee approval was waived by the regional health research authority. Patients, who had known iodinated contrast medium allergy, contraindications to β-blockers, atrial fibrillation, and indications other than suspected coronary artery disease, were excluded from analysis. The ultimate study population of 662 were analysed with details of intravenous metoprolol doses, complications, heart rate before administration of intravenous metoprolol (resting heart rate, RHR), heart rate at acquisition of scan (acquisition heart rate, AHR), and usage of low radiation dose protocols.
Of the ultimate study population of 662 patients, 183 had no intravenous metoprolol with mean acquisition heart rate (AHR) of 58 beats per minute (bpm), 257 had 1-15 mg intravenous metoprolol with mean AHR of 57 bpm, 114 had 16-29 mg intravenous metoprolol with mean AHR of 62 bpm and 108 had ≥30 mg intravenous metoprolol with mean AHR of 66 bpm. In the group receiving intravenous metoprolol, average usage was 19 mg (maximum 67 mg) with average reduction in HR of 15 bpm. There were no clinical incidents in relation to the use of high-dose intravenous metoprolol.
Higher doses of intravenous metoprolol are beneficial in achieving target heart rates to facilitate usage of low radiation dose protocols. With appropriate exclusion criteria, higher doses of intravenous metoprolol, well in excess of 15 mg, can be safely administered when carefully titrated.
评估高剂量静脉美托洛尔在计算机断层（CT）冠状动脉造影中降低心率的应用、安全性和疗效。
由于这是对匿名数据的回顾性分析，因此区域卫生研究机构免除了医学伦理委员会的批准。排除对碘造影剂过敏、β受体阻滞剂禁忌、心房颤动以及疑似冠心病以外适应证的患者。对最终的 662 例患者进行静脉美托洛尔剂量、并发症、静脉美托洛尔给药前心率（静息心率，RHR）、扫描采集时心率（采集心率，AHR）和低辐射剂量方案使用情况的详细分析。
在最终的 662 例患者中，183 例未使用静脉美托洛尔，平均采集心率（AHR）为 58 次/分钟（bpm），257 例使用 1-15mg 静脉美托洛尔，平均 AHR 为 57bpm，114 例使用 16-29mg 静脉美托洛尔，平均 AHR 为 62bpm，108 例使用≥30mg 静脉美托洛尔，平均 AHR 为 66bpm。在接受静脉美托洛尔治疗的患者中，平均用量为 19mg（最大 67mg），平均 HR 降低 15bpm。使用高剂量静脉美托洛尔无临床不良事件。
静脉美托洛尔的较高剂量有益于达到目标心率，从而有利于使用低辐射剂量方案。在适当的排除标准下，当谨慎滴定时，可安全给予剂量明显高于 15mg 的静脉美托洛尔。
