Nakayama Masafumi, Uchiyama Takashi, Tanaka Nobuhiro, Ohkawauchi Takaaki, Miwa Shunsuke, Hijikata Nobuhiro, Kobori Yuichi, Matsuo Hitoshi, Iwasaki Kiyotaka
Cardiovascular Center, Todachuo General Hospital Toda Japan.
Cooperative Major in Advanced Biomedical Sciences, Joint Graduate School of Tokyo Women's Medical University and Waseda University Tokyo Japan.
Circ Rep. 2020 Oct 23;2(11):665-673. doi: 10.1253/circrep.CR-20-0099.
We hypothesized that the intracoronary-electrocardiogram (IC-ECG)-based pressure index would be more stable and precise than the instantaneous flow reserve (iFR). We investigated the usefulness of the IC-ECG-based pressure index for diagnosing myocardial ischemia. Thirty-seven consecutive patients with coronary stenosis requiring physiological assessment were enrolled in the study. iFR was measured at rest and under hyperemia in 51 and 40 lesions, respectively. The IC-ECG-triggered distal pressure (Pd)/aortic pressure (Pa) ratio (ICE-T) was defined as the mean Pd/Pa ratio in the period corresponding to the isoelectric line. The ICE-T was significantly lower than the iFR both at rest and during hyperemia (P<0.00001 for both). Fluctuations in the ICE-T pressure parameters (Pd/Pa, Pa, and Pd) were significantly smaller than those of iFR both at rest and during hyperemia. The diagnostic accuracy of predicting a fractional flow reserve (FFR) ≤0.80 of the ICE-T at rest was significantly higher than that of iFR (P=0.008). Receiver operating characteristic curve analyses showed that the ICE-T predicts FFR ≤0.80 more accurately than the iFR (area under curve 0.897 vs. 0.810 for ICE-T and iFR, respectively). We identified the period in the IC-ECG in which resting Pd/Pa was low and constant. The IC-ECG-based algorithm may improve the accuracy of diagnosing myocardial ischemia, without increasing invasiveness, compared with pressure-dependent indices.
我们假设基于冠状动脉内心电图（IC-ECG）的压力指数比瞬时血流储备（iFR）更稳定、更精确。我们研究了基于IC-ECG的压力指数在诊断心肌缺血方面的实用性。37例连续的需要进行生理评估的冠状动脉狭窄患者纳入本研究。分别在51个和40个病变处测量静息和充血状态下的iFR。IC-ECG触发的远端压力（Pd）/主动脉压力（Pa）比值（ICE-T）定义为与等电位线对应的时间段内的平均Pd/Pa比值。静息和充血时ICE-T均显著低于iFR（两者P<0.00001）。静息和充血时，ICE-T压力参数（Pd/Pa、Pa和Pd）的波动均显著小于iFR。静息时预测ICE-T的血流储备分数（FFR）≤0.80的诊断准确性显著高于iFR（P=0.008）。受试者工作特征曲线分析表明，ICE-T预测FFR≤0.80比iFR更准确（ICE-T和iFR的曲线下面积分别为0.897和0.810）。我们确定了IC-ECG中静息Pd/Pa较低且恒定的时间段。与依赖压力的指标相比，基于IC-ECG的算法可能在不增加侵入性的情况下提高心肌缺血的诊断准确性。
