Hecht Sébastien, Annabi Mohamed-Salah, Stanová Viktória, Dahou Abdellaziz, Burwash Ian G, Koschutnik Matthias, Bartko Philipp E, Bergler-Klein Jutta, Mascherbauer Julia, Donà Carolina, Orwat Stefan, Baumgartner Helmut, Cavalcante Joao L, Ribeiro Henrique B, Théron Alexis, Rodes-Cabau Josep, Clavel Marie-Annick, Pibarot Philippe
Institut Universitaire de Cardiologie et de Pneumologie, Université Laval, Québec, Canada.
Division of Cardiology, University of Ottawa Heart Institute, Ottawa, Ontario, Canada.
JACC Adv. 2024 Sep 6;3(10):101245. doi: 10.1016/j.jacadv.2024.101245. eCollection 2024 Oct.
In patients with low-gradient (LG) aortic stenosis (AS), confirming disease severity and indication of intervention often requires dobutamine stress echocardiography (DSE) or aortic valve calcium scoring by computed tomography. We hypothesized that the mean transvalvular pressure gradient to effective orifice area ratio (MG/EOA, in mm Hg/cm) measured during rest echocardiography identifies true-severe AS (TSAS) and is associated with clinical outcomes in patients with low-flow, LG-AS.
The purpose of this study was to evaluate the diagnostic and prognostic value of MG/EOA ratio.
The diagnostic accuracy of MG/EOA ratio to identify TSAS was retrospectively assessed in: 1) an in vitro data set obtained in a circulatory model including 93 experimental conditions; and 2) an in vivo data set of 188 patients from the TOPAS (True or Pseudo-Severe Aortic Stenosis) study (NCT01835028). Receiver operating characteristic curves were used to assess the diagnostic accuracy of MG/EOA ratio for identifying TSAS, and Cox proportional hazards regression analyses were performed to assess its association with clinical outcomes.
The optimal cutoff of MG/EOA ratio to identify TSAS in patients with low-flow, LG-AS was ≥25 mm Hg/cm (correct classification 85%), as well as in vitro (100%). During a median follow-up of 1.41 ± 0.75 years, 146 (78%) patients met the composite endpoint of aortic valve replacement or all-cause mortality. A MG/EOA ratio ≥25 mm Hg/cm was independently associated with an increased risk of the composite endpoint (adjusted HR: 2.36 [95% CI: 1.63-3.42], < 0.001). The Harell's C-index of MG/EOA was 0.68, equaling projected EOA (0.67) measured by DSE.
MG/EOA ratio can be useful in low-flow, LG-AS to confirm AS severity and may complement DSE or aortic valve calcium scoring.
在低跨瓣压差（LG）的主动脉瓣狭窄（AS）患者中，确定疾病严重程度和干预指征通常需要多巴酚丁胺负荷超声心动图（DSE）或计算机断层扫描的主动脉瓣钙化评分。我们假设，静息超声心动图测量的平均跨瓣压差与有效瓣口面积之比（MG/EOA，单位为mmHg/cm）可识别真正严重的AS（TSAS），并与低流量、LG-AS患者的临床结局相关。
本研究旨在评估MG/EOA比值的诊断和预后价值。
回顾性评估MG/EOA比值识别TSAS的诊断准确性：1）在包括93种实验条件的循环模型中获得的体外数据集；2）来自TOPAS（真性或假性严重主动脉瓣狭窄）研究（NCT01835028）的188例患者的体内数据集。采用受试者工作特征曲线评估MG/EOA比值识别TSAS的诊断准确性，并进行Cox比例风险回归分析以评估其与临床结局的相关性。
在低流量、LG-AS患者中，识别TSAS的MG/EOA比值最佳截断值为≥25mmHg/cm（正确分类率85%），在体外实验中为100%。在中位随访1.41±0.75年期间，146例（78%）患者达到主动脉瓣置换或全因死亡的复合终点。MG/EOA比值≥25mmHg/cm与复合终点风险增加独立相关（校正HR：2.36[95%CI：1.63-3.42]，P<0.001）。MG/EOA的Harell's C指数为0.68，与DSE测量的预计EOA（0.67）相当。
MG/EOA比值在低流量、LG-AS中有助于确认AS严重程度，可能补充DSE或主动脉瓣钙化评分。
