Department of Medicine, Queen's University, Kingston, ON, Canada.
Department of Pathology and Molecular Medicine, Queen's University, Kingston, ON, Canada.
Haemophilia. 2023 Sep;29(5):1306-1312. doi: 10.1111/hae.14825. Epub 2023 Jul 10.
Severe aortic stenosis (AS) can lead to degradation of high molecular weight (HMW) von Willebrand factor (VWF) which can result in haemostatic abnormalities. While studies have explored changes in VWF profiles before and after surgical aortic valve replacement (SAVR), the longer-term changes in VWF profiles pre- and post-transcatheter aortic valve implantation (TAVI) are less understood.
Our primary objective was to identify differences in VWF multimer profiles and VWF function pre-TAVI and 1-month post-TAVI. Our secondary objective was to correlate VWF markers with measures of AS severity.
Adult patients with severe AS referred for TAVI at our institution were prospectively enrolled in this cohort study. Blood samples were collected for plasma analysis at three time points for all patients: 1 day pre-TAVI, 3 days post-TAVI, and 1-month post-TAVI. VWF antigen, activity, propeptide, collagen binding, multimers, and factor VIII coagulant activity were determined at each time point. Correlations between VWF parameters and severity of AS were assessed.
Twenty participants (15 males, five females) with severe AS were recruited for the study. There was a significant increase in HMW VWF between pre-procedure and 1-month post-TAVI (p < .05). There was a transient increase in VWF antigen levels and activity at 3-days post TAVI that decreased to pre-TAVI levels at 1-month. There were no statistically significant correlations between VWF markers and AS severity.
This is the first study to elucidate longer-term (>1 week) improvements in HMW VWF after a TAVI procedure in severe AS patients.
严重的主动脉瓣狭窄（AS）可导致高分子量（HMW）血管性血友病因子（VWF）降解，从而导致止血异常。虽然已经研究了主动脉瓣置换术（SAVR）前后 VWF 谱的变化，但经导管主动脉瓣植入术（TAVI）前后 VWF 谱的长期变化知之甚少。
我们的主要目的是确定 TAVI 前后 VWF 多聚体谱和 VWF 功能的差异。我们的次要目标是将 VWF 标志物与 AS 严重程度的指标相关联。
我们对我院接受 TAVI 的严重 AS 成年患者进行了这项前瞻性队列研究。所有患者在三个时间点采集血浆样本进行分析：TAVI 前 1 天、TAVI 后 3 天和 TAVI 后 1 个月。在每个时间点测定 VWF 抗原、活性、前肽、胶原结合、多聚体和因子 VIII 凝血活性。评估 VWF 参数与 AS 严重程度之间的相关性。
这项研究共纳入 20 名严重 AS 患者（15 名男性，5 名女性）。与术前相比，TAVI 后 1 个月 HMW VWF 显著增加（p <.05）。TAVI 后 3 天 VWF 抗原水平和活性短暂升高，1 个月时降至术前水平。VWF 标志物与 AS 严重程度之间无统计学显著相关性。
这是第一项研究表明，在严重 AS 患者中，TAVI 后 HMW VWF 的长期（>1 周）改善。
