Meuwissen M, Chamuleau S A, Siebes M, Schotborgh C E, Koch K T, de Winter R J, Bax M, de Jong A, Spaan J A, Piek J J
Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
Circulation. 2001 Jan 16;103(2):184-7. doi: 10.1161/01.cir.103.2.184.
Fractional flow reserve (FFR) and coronary blood flow velocity reserve (CFR) represent physiological quantities used to evaluate coronary lesion severity and to make clinical decisions. A comparison between the outcomes of both diagnostic techniques has not been performed in a large cohort of patients with intermediate coronary lesions.
FFR and CFR were assessed in 126 consecutive patients with 150 intermediate coronary lesions (between 40% and 70% diameter stenosis by visual assessment). Agreement between outcomes of FFR and CFR, categorized at cut-off values of 0.75 and 2.0, respectively, was observed in 109 coronary lesions (73%), whereas discordant outcomes were present in 41 lesions (27%). In 26 of these 41 lesions, FFR was <0.75 and CFR>or=2.0 (group A); in the remaining 15 lesions, FFR was >or=0.75 and CFR<2.0 (group B). Minimum microvascular resistance, defined as the ratio of mean distal pressure to average peak blood flow velocity during maximum hyperemia, showed a large variability (overall range, 0.65 to 4.64 mm Hg x cm(-1) x s(-1)) and was significantly higher in group B than in group A (2.42+/-0.77 versus 1.91+/-0.70 mm Hg x cm(-1) x s(-1); P:=0.034).
Our findings demonstrate the prominent role of microvascular resistance in modulating the relationship between FFR and CFR and emphasize the importance of combined pressure and flow velocity measurements to evaluate coronary lesion severity and microvascular involvement.
血流储备分数（FFR）和冠状动脉血流速度储备（CFR）是用于评估冠状动脉病变严重程度及做出临床决策的生理学指标。尚未在一大群患有中度冠状动脉病变的患者中对这两种诊断技术的结果进行比较。
对126例连续的患者的150处中度冠状动脉病变（通过视觉评估直径狭窄40%至70%）进行了FFR和CFR评估。在109处冠状动脉病变（73%）中观察到FFR和CFR结果之间的一致性，分别以0.75和2.0为临界值进行分类，而41处病变（27%）存在不一致的结果。在这41处病变中的26处，FFR<0.75且CFR≥2.0（A组）；在其余15处病变中，FFR≥0.75且CFR<2.0（B组）。最小微血管阻力定义为最大充血期间平均远端压力与平均峰值血流速度之比，显示出很大的变异性（总体范围为0.65至4.64 mmHg×cm⁻¹×s⁻¹），且B组显著高于A组（2.42±0.77对1.91±0.70 mmHg×cm⁻¹×s⁻¹；P = 0.034）。
我们的研究结果证明了微血管阻力在调节FFR和CFR之间关系中的重要作用，并强调了联合压力和流速测量对于评估冠状动脉病变严重程度和微血管受累情况的重要性。
