Division of Cardiovascular Medicine, Department of Internal Medicine, Kobe University Graduate School of Medicine, 7-5-1 Kusunoki-cho, Chuo-ku, Kobe, Hyogo, 650-0017, Japan.
Heart Vessels. 2024 Aug;39(8):735-745. doi: 10.1007/s00380-024-02387-5. Epub 2024 Mar 25.
Murray law-based quantitative flow ratio (μQFR) is a novel computational method that enables accurate estimation of fractional flow reserve (FFR) using a single angiographic projection. However, its diagnostic value in patients with severe aortic stenosis (AS) remains unclear.
We included 25 consecutive patients who underwent transcatheter aortic valve replacement (TAVR) for severe AS with intermediate or greater (30-90%) coronary artery disease (CAD). Pre- and post-TAVR μQFR, QFR, instantaneous flow reserve (iFR), and post-TAVR invasive FFR values were measured. We evaluated the diagnostic performance of pre-TAVR μQFR, QFR, and iFR using post-TAVR FFR ≤ 0.80 as a reference standard of ischemia.
Pre-TAVR μQFR was significantly correlated with post-TAVR FFR (r = 0.73, p < 0.0001). The area under the curve of pre-TAVR μQFR on post-TAVR FFR ≤ 0.8 was 0.91 (95% confidence interval [CI] 0.77-0.98), comparable to that of pre-TAVR iFR (0.86 [95% CI 0.71-0.98], p = 0.97). The accuracy, sensitivity, specificity, and positive and negative predictive values of pre-TAVR μQFR on post-TAVR FFR ≤ 0.8 were 84.2% (95% CI 68.7-93.4), 61.6% (95% CI 31.6-86.1), 96.0% (95% CI 79.6-99.9), 88.9% (95% CI 52.9-98.3), and 82.8% (95% CI 70.6-90.6), respectively. For pre-TAVR iFR, these values were 76.5% (95% CI 58.8-89.3), 90.9% (95% CI 58.7-99.8), 69.6% (95% CI 47.1-86.8), 58.8% (95% CI 42.8-73.1), and 94.1% (95% CI 70.8-99.1), respectively.
μQFR could be useful for the physiological evaluation of patients with severe AS with concomitant CAD.
基于 Murray 定律的定量血流比（μQFR）是一种新的计算方法，可通过单次血管造影投影准确估计血流储备分数（FFR）。然而，其在伴有中度至重度（30-90%）冠状动脉疾病（CAD）的严重主动脉瓣狭窄（AS）患者中的诊断价值尚不清楚。
我们纳入了 25 例连续接受经导管主动脉瓣置换术（TAVR）治疗严重 AS 且伴有中度至重度（30-90%）CAD 的患者。测量了术前和术后 TAVR 的 μQFR、QFR、即时血流储备（iFR）和术后 TAVR 有创 FFR 值。我们使用术后 TAVR FFR≤0.8 作为缺血的参考标准，评估了术前 μQFR、QFR 和 iFR 的诊断性能。
术前 μQFR 与术后 TAVR FFR 呈显著相关（r=0.73，p<0.0001）。术前 μQFR 对术后 TAVR FFR≤0.8 的曲线下面积为 0.91（95%置信区间[CI]0.77-0.98），与术前 iFR 相当（0.86[95%CI0.71-0.98]，p=0.97）。术前 μQFR 对术后 TAVR FFR≤0.8 的准确性、敏感度、特异度、阳性预测值和阴性预测值分别为 84.2%（95%CI68.7-93.4）、61.6%（95%CI31.6-86.1）、96.0%（95%CI79.6-99.9）、88.9%（95%CI52.9-98.3）和 82.8%（95%CI70.6-90.6）。对于术前 iFR，这些值分别为 76.5%（95%CI58.8-89.3）、90.9%（95%CI58.7-99.8）、69.6%（95%CI47.1-86.8）、58.8%（95%CI42.8-73.1）和 94.1%（95%CI70.8-99.1）。
μQFR 可用于评估伴有 CAD 的严重 AS 患者的生理学状况。
