Hebbar Ullhas Udaya, Effat Mohamed A, Peelukhana Srikara V, Arif Imran, Banerjee Rupak K
Department of Mechanical and Materials Engineering, University of Cincinnati, Cincinnati, OH 45221, United States.
Division of Cardiovascular Diseases, University of Cincinnati Medical Center, Veteran Affairs Medical Center, Cincinnati, OH 45221, United States.
World J Cardiol. 2017 Dec 26;9(12):813-821. doi: 10.4330/wjc.v9.i12.813.
To investigate the patient-outcomes of newly developed pressure drop coefficient (CDP) in diagnosing epicardial stenosis (ES) in the presence of concomitant microvascular disease (MVD).
Patients from our clinical trial were divided into two subgroups with: (1) cut-off of coronary flow reserve (CFR) < 2.0; and (2) diabetes. First, correlations were performed for both subgroups between CDP and hyperemic microvascular resistance (HMR), a diagnostic parameter for assessing the severity of MVD. Linear regression analysis was used for these correlations. Further, in each of the subgroups, comparisons were made between fractional flow reserve (FFR) < 0.75 and CDP > 27.9 groups for assessing major adverse cardiac events (MACE: Primary outcome). Comparisons were also made between the survival curves for FFR < 0.75 and CDP > 27.9 groups. Two tailed chi-squared and Fischer's exact tests were performed for comparison of the primary outcomes, and the log-rank test was used to compare the Kaplan-Meier survival curves. < 0.05 for all tests was considered statistically significant.
Significant linear correlations were observed between CDP and HMR for both CFR < 2.0 ( = 0.58, < 0.001) and diabetic ( = 0.61, < 0.001) patients. In the CFR < 2.0 subgroup, the %MACE (primary outcomes) for CDP > 27.9 group (7.7%, 2/26) was lower than FFR < 0.75 group (3/14, 21.4%); = 0.21. Similarly, in the diabetic subgroup, the %MACE for CDP > 27.9 group (12.5%, 2/16) was lower than FFR < 0.75 group (18.2%, 2/11); P = 0.69. Survival analysis for CFR < 2.0 subgroup indicated better event-free survival for CDP > 27.9 group ( = 26) when compared with FFR < 0.75 group ( = 14); = 0.10. Similarly, for the diabetic subgroup, CDP > 27.9 group ( = 16) showed higher survival times compared to FFR group ( = 11); = 0.58.
CDP correlated significantly with HMR and resulted in better %MACE as well as survival rates in comparison to FFR. These positive trends demonstrate that CDP could be a potential diagnostic endpoint for delineating MVD with or without ES.
研究新开发的压力降系数（CDP）在合并微血管疾病（MVD）情况下诊断心外膜狭窄（ES）时的患者预后。
我们临床试验中的患者被分为两个亚组：（1）冠状动脉血流储备（CFR）<2.0；（2）糖尿病。首先，对两个亚组分别进行CDP与充血性微血管阻力（HMR，评估MVD严重程度的诊断参数）之间的相关性分析。这些相关性采用线性回归分析。此外，在每个亚组中，对血流储备分数（FFR）<0.75组和CDP>27.9组进行比较，以评估主要不良心脏事件（MACE：主要结局）。还对FFR<0.75组和CDP>27.9组的生存曲线进行了比较。采用双侧卡方检验和费舍尔精确检验比较主要结局，采用对数秩检验比较Kaplan-Meier生存曲线。所有检验P<0.05被认为具有统计学意义。
对于CFR<2.0（r=0.58，P<0.001）和糖尿病患者（r=0.61，P<0.001），CDP与HMR之间均观察到显著的线性相关性。在CFR<2.0亚组中，CDP>27.9组的MACE百分比（主要结局）（7.7%，2/26）低于FFR<0.75组（3/14，21.4%）；P=0.21。同样，在糖尿病亚组中，CDP>27.9组的MACE百分比（12.5%，2/16）低于FFR<0.75组（18.2%，2/11）；P=0.69。CFR<2.0亚组的生存分析表明，与FFR<0.75组（n=14）相比，CDP>27.9组（n=26）的无事件生存率更好；P=0.10。同样，对于糖尿病亚组，CDP>27.9组（n=16）的生存时间高于FFR组（n=11）；P=0.58。
CDP与HMR显著相关，与FFR相比，其MACE百分比和生存率更佳。这些积极趋势表明，CDP可能是区分有无ES的MVD的潜在诊断终点。
