Banerjee Rupak K, Ramadurai Sruthi, Manegaonkar Shreyash M, Rao Marepalli B, Rakkimuthu Sathyaprabha, Effat Mohamed A
Department of Mechanical and Materials Engineering, University of Cincinnati, Cincinnati, OH, United States.
Research Services, Veteran Affairs Medical Services, Cincinnati, OH, United States.
Front Physiol. 2021 Jul 14;12:689517. doi: 10.3389/fphys.2021.689517. eCollection 2021.
The current pressure-based coronary diagnostic index, fractional flow reserve (FFR), has a limited efficacy in the presence of microvascular disease (MVD). To overcome the limitations of FFR, the objective is to assess the recently introduced pressure drop coefficient (CDP), a fundamental fluid dynamics-based combined pressure-flow index.
We hypothesize that CDP will result in improved clinical outcomes in comparison to FFR. To test the hypothesis, chi-square test was performed to compare the percent major adverse cardiac events (%MACE) at 5 years between (a) FFR < 0.75 and CDP > 27.9 and (b) FFR < 0.80 and CDP > 25.4 groups using a prospective cohort study. Furthermore, Kaplan-Meier survival curves were compared between the FFR and CDP groups. The results were considered statistically significant for < 0.05. The outcomes of the CDP arm were presumptive as clinical decision was solely based on the FFR.
For the complete patient group, the %MACE in the CDP > 27.9 group (10 out of 35, 29%) was lower in comparison to the FFR < 0.75 group (11 out of 20, 55%), and the difference was near significant ( = 0.05). The survival analysis showed a significantly higher survival rate ( = 0.01) in the CDP > 27.9 group ( = 35) when compared to the FFR < 0.75 group ( = 20). The results remained similar for the FFR = 0.80 cutoff. The comparison of the 5-year MACE outcomes with the 1-year outcomes for the complete patient group showed similar trends, with a higher statistical significance for a longer follow-up period of 5 years.
Based on the MACE and survival analysis outcomes, CDP could possibly be an alternate diagnostic index for decision-making in the cardiac catheterization laboratory.
www.ClinicalTrials.gov, identifier NCT01719016.
当前基于压力的冠状动脉诊断指标——血流储备分数（FFR），在存在微血管疾病（MVD）时疗效有限。为克服FFR的局限性，目的是评估最近引入的压力降系数（CDP），这是一种基于基本流体动力学的联合压力-流量指标。
我们假设与FFR相比，CDP将带来更好的临床结果。为验证该假设，采用前瞻性队列研究，通过卡方检验比较（a）FFR<0.75且CDP>27.9组与（b）FFR<0.80且CDP>25.4组5年时的主要不良心脏事件发生率（%MACE）。此外，比较了FFR组和CDP组的Kaplan-Meier生存曲线。结果在P<0.05时被认为具有统计学意义。CDP组的结果为推测性结果，因为临床决策仅基于FFR。
对于完整患者组，CDP>27.9组的%MACE（35例中有10例，29%）低于FFR<0.75组（20例中有11例，55%），差异接近显著（P = 0.05）。生存分析显示，与FFR<0.75组（n = 20）相比，CDP>27.9组（n = 35）的生存率显著更高（P = 0.01）。对于FFR = 0.80的临界值，结果相似。完整患者组5年MACE结果与1年结果的比较显示出相似趋势，5年更长随访期的统计学意义更高。
基于MACE和生存分析结果，CDP可能是心脏导管实验室决策的替代诊断指标。
