Acharya Metesh, Valencia Oswaldo, Edsell Mark, Tome Maite, Morgan Robert, Nowell Justin, Jahangiri Marjan
Department of Cardiothoracic Surgery, St. George's Hospital, London, UK.
Department of Anaesthesia, St. George's Hospital, London, UK.
Ann Med Surg (Lond). 2021 Apr 18;65:102342. doi: 10.1016/j.amsu.2021.102342. eCollection 2021 May.
Aortic dissection is a life-threatening complication of bicuspid aortic valve (BAV)-associated aortopathy. In these populations, whilst prophylactic replacement of proximal thoracic aortic aneurysms (TAAs) is generally recommended at threshold diameters ≥5.5 cm, dissection may occur in smaller aortas. An alternative size-based parameter, the cross-sectional aortic area/patient height ratio (indexed aortic area, IAA), correlates with increased dissection risk at abnormal values > 10 cm/m. We sought to assess the utility of the IAA in identifying at-risk BAV-associated TAAs with abnormal IAA, albeit with sub-threshold aortic diameter.
We retrospectively identified 69 patients with BAV-associated TAAs who underwent surgical repair between 2010 and 2016. Aortic diameter was measured on pre-operative imaging, and IAA calculated, at the mid-sinus of Valsalva, sino-tubular junction and mid-ascending aorta for each patient. We determined proportions of aneurysms with IAA >10 cm/m, median IAAs corresponding to aortic diameters <4.0 cm, 4.0-4.5 cm, 4.5-5.0 cm, 5.0-5.5 cm and >5.5 cm, and median aortic diameters corresponding to an abnormal IAA.
50.9%, 12.5% and 64.6% of aneurysms at the sinus of Valsalva, sino-tubular junction and mid-ascending aorta, respectively, had an abnormal IAA. 51.9% and 88.9% of patients with aortic diameter 4.5-5.0 cm and 5.0-5.5 cm, respectively, had an abnormal IAA. In aneurysms with abnormal IAA involving the sinus of Valsalva, sino-tubular junction, and mid-ascending aorta, median aortic diameters were 4.98 cm, 5.04 cm and 5.11 cm, respectively. Overall, 57/72 (79.2%) at-risk aneurysms with IAA >10 cm/m had diameters smaller than the 5.5 cm guideline cut-off for surgical intervention.
Significant proportions of BAV-associated TAAs are at increased risk of aortic dissection attending an IAA >10 cm/m, whilst not fulfilling the size criteria indicating aortic surgery in contemporary guidelines. Further analysis of IAA in larger BAV cohorts is necessary to clarify its role in patient selection and optimal timing for prophylactic aortic replacement.
主动脉夹层是二叶式主动脉瓣（BAV）相关主动脉病变的一种危及生命的并发症。在这些人群中，虽然一般建议在近端胸主动脉瘤（TAA）直径≥5.5 cm时进行预防性置换，但较小的主动脉也可能发生夹层。另一个基于尺寸的参数，即主动脉横截面积/患者身高比值（指数化主动脉面积，IAA），在IAA值>10 cm/m时与夹层风险增加相关。我们试图评估IAA在识别IAA异常的高危BAV相关TAA中的作用，尽管这些TAA的主动脉直径未达到阈值。
我们回顾性地确定了2010年至2016年间接受手术修复的69例BAV相关TAA患者。在术前影像学上测量主动脉直径，并计算每位患者在主动脉瓣窦中部、窦管交界处和升主动脉中部的IAA。我们确定了IAA>10 cm/m的动脉瘤比例、对应主动脉直径<4.0 cm、4.0 - 4.5 cm、4.5 - 5.0 cm、5.0 - 5.5 cm和>5.5 cm的IAA中位数，以及对应异常IAA的主动脉直径中位数。
主动脉瓣窦、窦管交界处和升主动脉中部的动脉瘤分别有50.9%、12.5%和64.6%的IAA异常。主动脉直径在4.5 - 5.0 cm和5.0 - 5.5 cm的患者中，分别有51.9%和88.9%的IAA异常。在IAA异常且累及主动脉瓣窦、窦管交界处和升主动脉中部的动脉瘤中，主动脉直径中位数分别为4.98 cm、5.04 cm和5.11 cm。总体而言，57/72（79.2%）IAA>10 cm/m的高危动脉瘤直径小于手术干预的5.5 cm指南临界值。
相当比例的BAV相关TAA在IAA>10 cm/m时主动脉夹层风险增加，而未达到当代指南中指示主动脉手术的尺寸标准。有必要在更大的BAV队列中对IAA进行进一步分析，以阐明其在患者选择和预防性主动脉置换最佳时机方面的作用。
