Smidt Heart Institute, Cedars Sinai Medical Center, Los Angeles, California, USA; Mark Taper Imaging Institute, Cedars Sinai Medical Center Los Angeles, California, USA.
Mark Taper Imaging Institute, Cedars Sinai Medical Center Los Angeles, California, USA.
JACC Cardiovasc Imaging. 2020 Dec;13(12):2591-2601. doi: 10.1016/j.jcmg.2020.07.045. Epub 2020 Oct 28.
The association between extracellular volume (ECV) measured by computed tomography angiography (CTA) and clinical outcomes was evaluated in low-flow low-gradient (LFLG) aortic stenosis (AS) patients undergoing transcatheter aortic valve replacement (TAVR).
Patients with LFLG AS comprise a high-risk group with respect to clinical outcomes. Although ECV, a marker of myocardial fibrosis, is traditionally measured with cardiac magnetic resonance, it can also be measured using cardiac CTA. The authors hypothesized that in LFLG AS, increased ECV may be associated with adverse clinical outcomes.
In 150 LFLG patients with AS who underwent TAVR, ECV was quantified using pre-TAVR CTA. Echocardiographic and clinical information including all-cause death and heart failure rehospitalization (HFH) was obtained from electronic medical records. A Cox proportional hazards model was used to evaluate the association between ECV and death+HFH.
During a median follow-up of 13.9 months (range 0.07 to 28.9 months), there were 31 death+HFH events (21%). Patients who experienced death+HFH had a greater median Society of Thoracic Surgery score (9.9 vs. 4.7; p < 0.01), lower left ventricular ejection fraction (42.3 ± 20.2% vs. 52.7 ± 17.2%; p < 0.01), lower mean transvalvular gradient (24.9 ± 8.9 mm Hg vs. 28.1 ± 7.3 mm Hg; p = 0.04) and increased mean ECV (35.5 ± 9.6% vs. 29.9 ± 8.2%; p < 0.01) compared with patients who did not experience death+HFH. In a multivariable Cox proportional hazards model, increase in ECV was associated with increase in death+HFH, (hazard ratio per 1% increase: 1.04, 95% confidence interval: 1.01 to 1.09; p < 0.01).
In patients with LFLG AS, CTA measured increase in ECV is associated with increased risk of adverse clinical outcomes post-TAVR and may thus serve as a useful noninvasive marker for prognostication.
评估经计算机断层扫描血管造影术（CTA）测量的细胞外容积（ECV）与低流量低梯度（LFLG）主动脉瓣狭窄（AS）患者行经导管主动脉瓣置换术（TAVR）后的临床结局之间的关系。
LFLG AS 患者的临床结局风险较高。尽管心肌纤维化标志物 ECV 传统上采用心脏磁共振进行测量，但也可以使用心脏 CTA 进行测量。作者假设在 LFLG AS 中，ECV 的增加可能与不良临床结局相关。
在 150 例接受 TAVR 的 LFLG AS 患者中，使用术前 CTA 定量 ECV。从电子病历中获取超声心动图和临床信息，包括全因死亡和心力衰竭再入院（HFH）。采用 Cox 比例风险模型评估 ECV 与死亡+HFH 之间的关系。
中位随访时间为 13.9 个月（范围 0.07 至 28.9 个月），共有 31 例死亡+HFH 事件（21%）。经历死亡+HFH 的患者的 Society of Thoracic Surgery 评分中位数更高（9.9 分比 4.7 分；p<0.01），左心室射血分数更低（42.3±20.2%比 52.7±17.2%；p<0.01），平均跨瓣梯度更低（24.9±8.9mmHg 比 28.1±7.3mmHg；p=0.04），平均 ECV 更高（35.5±9.6%比 29.9±8.2%；p<0.01）。在多变量 Cox 比例风险模型中，ECV 的增加与死亡+HFH 的增加相关（每增加 1%的风险比：1.04，95%置信区间：1.01 至 1.09；p<0.01）。
在 LFLG AS 患者中，CTA 测量的 ECV 增加与 TAVR 后不良临床结局的风险增加相关，因此可能成为一种有用的预后无创标志物。
