Abstract：
Limited type A aortic dissection (LTAAD) is a rare subtype of dissection that is confined within a well-defined border of the ascending aorta. These dissections may occur in the remaining native portion of the aortic root following aortic root replacement and can be complicated by malperfusion syndrome-a syndrome where dissections compromise the aortic branches and lead to end-organ ischemia. Because LTAAD is confined within the ascending aorta, malperfusion syndrome may preferentially affect the coronary arteries resulting in coronary malperfusion, myocardial infarction, and increased mortality. We report a case of LTAAD and malperfusion syndrome of the left main coronary artery which resulted in inadequate contrast opacification of the aorta and failure of the dissection protocol to trigger on computed tomography (CT). Upon further evaluation of the situation, the radiologist oversaw the manual triggering of CT acquisitions which yielded an actionable CT at 6 minutes post-contrast and real-time visualization of the patient\'s developing cardiac ischemia.
摘要：
限制性A型主动脉夹层（LTAAD）是一种罕见的夹层亚型，局限于升主动脉的明确边界内。这些夹层可能发生在主动脉根置换后的主动脉根的剩余天然部分，并且可能因灌注不良综合征而复杂化，该综合征是解剖损害主动脉分支并导致终末器官缺血的综合征。因为LTAAD局限于升主动脉内,灌注不良综合征可能优先影响冠状动脉，导致冠状动脉灌注不良，心肌梗塞,和死亡率增加。我们报告了一例LTAAD和左主冠状动脉灌注不良综合征，导致主动脉造影混浊不足，夹层方案无法触发计算机断层扫描（CT）。经进一步评估,放射科医师监督了CT采集的手动触发,在造影后6分钟时产生了可操作的CT,并实时显示了患者正在发生的心肌缺血.
