Patel Amar D, Lerakis Stamatios, Zacharoulis Achilles, Martin Randolph P
Division of Cardiology, University of Medicine, Emory University, Atlanta, Georgia, USA.
J Am Soc Echocardiogr. 2005 May;18(5):486-9. doi: 10.1016/j.echo.2005.02.003.
Compared with the frequent occurrence of S-T segment depression, the development of S-T segment elevation during dobutamine stress echocardiography is a relatively rare finding, especially in the setting of nonobstructive coronary artery disease. We present two patients who developed chest discomfort with S-T segment elevation during dobutamine stress testing. Both patients had unremarkable baseline echocardiograms and no history suggestive of coronary vasospasm. Subsequent coronary angiography revealed nonobstructive disease. It is speculated that the likely presence of endothelial dysfunction coupled with mild coronary atherosclerosis caused an imbalance between the coronary vasodilatory and vasoconstrictive forces. The inhibition of the vasodilatory effects of beta-adrenergic receptor stimulation and flow-mediated dilation of dobutamine was overcome by the vasoconstrictive effects of dobutamine-stimulated alpha-1 receptor activation; thus, contributing to the development of coronary vasospasm. This condition is important to recognize and appreciate as the initial treatment for this condition favors the use of nitrates over beta-blockade.
与S-T段压低的频繁发生相比，多巴酚丁胺负荷超声心动图期间S-T段抬高的情况相对少见，尤其是在非阻塞性冠状动脉疾病的背景下。我们报告两名在多巴酚丁胺负荷试验期间出现伴有S-T段抬高的胸部不适的患者。两名患者的基线超声心动图均无异常，且无提示冠状动脉痉挛的病史。随后的冠状动脉造影显示为非阻塞性疾病。据推测，可能存在的内皮功能障碍与轻度冠状动脉粥样硬化导致冠状动脉血管舒张和血管收缩力之间失衡。多巴酚丁胺刺激α-1受体激活所产生的血管收缩作用克服了β-肾上腺素能受体刺激和多巴酚丁胺介导的血流介导舒张的血管舒张作用；因此，促成了冠状动脉痉挛的发生。认识和了解这种情况很重要，因为针对这种情况的初始治疗更倾向于使用硝酸盐而非β受体阻滞剂。
