Department of Internal Medicine in Jönköping, and Department of Health, Medicine and Caring Sciences, Linköping University, Länssjukhuset Ryhov, Sjukhusgatan, 551 85 Jönköping, Sweden.
Division of Diagnostics and Specialist Medicine, Department of Health, Medicine and Caring Sciences, Linköping University, Universitetssjukhuset, 581 83 Linköping, Sweden.
Eur Heart J Cardiovasc Imaging. 2024 Sep 30;25(10):1384-1393. doi: 10.1093/ehjci/jeae130.
Understanding the mechanisms underlying ascending aortic dilation is imperative for refined risk stratification of these patients, particularly among incidentally identified patients, most commonly presenting with tricuspid valves. The aim of this study was to explore associations between ascending aortic haemodynamics, assessed using four-dimensional flow cardiovascular magnetic resonance imaging (4D flow CMR), and circulating biomarkers in aortic dilation.
Forty-seven cases with aortic dilation (diameter ≥ 40 mm) and 50 sex-and age-matched controls (diameter < 40 mm), all with tricuspid aortic valves, underwent 4D flow CMR and venous blood sampling. Associations between flow displacement, wall shear stress (WSS), and oscillatory shear index in the ascending aorta derived from 4D flow CMR, and biomarkers including interleukin-6, collagen type I α1 chain, metalloproteinases (MMPs), and inhibitors of MMPs derived from blood plasma, were investigated. Cases with dilation exhibited lower peak systolic WSS, higher flow displacement, and higher mean oscillatory shear index compared with controls without dilation. No significant differences in biomarkers were observed between the groups. Correlations between haemodynamics and biomarkers were observed, particularly between maximum time-averaged WSS and interleukin-6 (r = 0.539, P < 0.001), and maximum oscillatory shear index and collagen type I α1 chain (r = -0.575, P < 0.001 in cases).
Significant associations were discovered between 4D flow CMR derived whole-cardiac cycle WSS and circulating biomarkers representing inflammation and collagen synthesis, suggesting an intricate interplay between haemodynamics and the processes of inflammation and collagen synthesis in patients with early aortic dilation and tricuspid aortic valves.
了解升主动脉扩张的机制对于这些患者的风险分层至关重要，尤其是在偶然发现的患者中，这些患者最常表现为三尖瓣。本研究旨在探讨使用四维血流心血管磁共振成像（4D 流 CMR）评估的升主动脉血流动力学与主动脉扩张患者循环生物标志物之间的相关性。
47 例升主动脉扩张（直径≥40mm）患者和 50 例性别和年龄匹配的对照组（直径<40mm），均为三尖瓣主动脉瓣，均行 4D 流 CMR 和静脉采血。探讨了 4D 流 CMR 得出的升主动脉血流位移、壁切应力（WSS）和脉动剪切指数与生物标志物（包括白细胞介素 6、I 型胶原α1链、基质金属蛋白酶（MMPs）和 MMPs 抑制剂）之间的相关性。与无扩张组相比，扩张组的收缩期峰值 WSS 较低，血流位移较高，平均脉动剪切指数较高。两组之间的生物标志物无显著差异。血流动力学与生物标志物之间存在相关性，尤其是最大时间平均 WSS 与白细胞介素 6（r=0.539，P<0.001），最大脉动剪切指数与 I 型胶原α1链（r=-0.575，P<0.001）。
发现 4D 流 CMR 得出的整个心动周期 WSS 与代表炎症和胶原蛋白合成的循环生物标志物之间存在显著相关性，提示在早期主动脉扩张和三尖瓣患者中，血流动力学与炎症和胶原蛋白合成过程之间存在复杂的相互作用。
