As a non-invasive diagnosis method, computed tomographic angiography-based computational fluid dynamics is used to estimate fractional flow reserve of coronary arteries (FFRct). However, FFRct uses hypothetical hemodynamic flow conditions, and thus FFRct might cause mismatches (fractional flow reserve > 0.8) with invasive fractional flow reserve (≤0.8). Additional computational fluid dynamics-based criteria are still needed to improve the accuracy of non-invasive diagnosis. In this article, a new concept of computed tomographic angiography-based flow resistance coefficient (FRCct) is proposed, and it tests pressure drops at coronary arteries under different blood flow rates and returns two constant flow resistance coefficients (A and B) for each artery. Specifically, 30 patients who were suspected to meet the treatment indication of their left anterior descending stenosis were tested with invasive fractional flow reserve and FRCct. The invasive fractional flow reserve divided the patients into a safe group (invasive fractional flow reserve > 0.8, 15 patients) and a sick group (invasive fractional flow reserve ≤ 0.8, 15 patients). A following FRCct indicated that the flow resistance coefficient always displayed a low value (A = 0.0039 ± 2.7e-5; B = 0.079 ± 0.0025) for the safe group, while the flow resistance coefficient always exhibited a high value (A = 0.0235 ± 0.001; B = 0.270 ± 0.108) for the sick group. The results of the statistical test indicated that the p-value was less than 0.05 for both A and B of the two groups. In conclusion, in addition to the FFRct, FRCct is a supplementary non-invasive method to evaluate the treatment indication of left anterior descending stenosis.

中文翻译：

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左前降支狭窄的流阻系数分析：初步研究。

作为一种非侵入性诊断方法，基于计算机断层摄影血管造影的计算流体动力学可用于估算冠状动脉的部分血流储备（FFRct）。但是，FFRct使用假设的血液动力学血流状况，因此FFRct可能导致侵入性分数血流储备（≤0.8）不匹配（分数血流储备> 0.8）。仍需要其他基于计算流体动力学的标准来提高非侵入性诊断的准确性。在本文中，提出了一种基于计算机断层摄影血管造影的流动阻力系数（FRCct）的新概念，它可以测试不同血流速率下冠状动脉的压降，并为每条动脉返回两个恒定的流动阻力系数（A和B） 。特别，对30名怀疑符合左前降支狭窄治疗指征的患者进行了有创分数血流储备和FRCct测试。侵入性部分血流储备将患者分为安全组（侵入性部分血流储备> 0.8，15例）和患病组（侵入性部分血流储备≤0.8，15例）。随后的FRCct表示安全组的流阻系数始终显示较低的值（A = 0.0039±2.7e-5; B = 0.079±0.0025），而流阻系数始终显示较高的值（A = 0.0235± 0.001; B = 0.270±0.108）。统计测试的结果表明，两组的A和B的p值均小于0.05。总之，除了FFRct，