Murasawa Takahide, Takahashi Masao, Myojo Masahiro, Kiyosue Arihiro, Oguri Atsushi, Ando Jiro, Komuro Issei
Department of Medical Engineering, The University of Tokyo Hospital.
Department of Cardiovascular Medicine, Graduate School of Medicine, The University of Tokyo.
Int Heart J. 2017 May 31;58(3):365-370. doi: 10.1536/ihj.16-479. Epub 2017 May 23.
Previous research revealed that, in patients with coronary pressure-derived fractional flow reserve (FFR) in the 'grey zone' (0.75-0.85), repeated FFR assessments sometimes yield conflicting results. One of the causes of the fluctuations in FFR values around the grey zone may be imprecise identification of the point where maximal hyperemia is achieved. Identification of the state of maximal hyperemia during assessment of FFR can be challenging. This study aimed to determine whether non-invasive electrical velocimetry (EV) can be used to identify the state of maximal hyperemia.Stroke volume (SV), SV variation (SVV), and systemic vascular resistance index (SVRI) were determined by EV in 15 patients who underwent FFR assessment. Time intervals from initiation of adenosine infusion to achieving maximal hyperemia (time), as well as to achieving maximal cardiac output (CO), SV, SVV, and SVRI (time, time, time, and time, respectively), were determined. Time and time were closer to time than other values (time/time versus time/time = 1.03 ± 0.2 versus 1.36 ± 0.4, P < 0.05). The maximum of SV was difficult to determine owing to considerable variations, but the maximum of SVV was clearly recognized. Time and time were significantly correlated with time, with time showing a stronger correlation than time (time: r = 0.92, P < 0.01; time: r = 0.80, P < 0.01).Maximal SVV is reached close to maximal hyperemia. Monitoring of SVV with non-invasive EV during FFR assessment can help identify the state of maximal hyperemia.
先前的研究表明，在冠状动脉压力衍生的血流储备分数（FFR）处于“灰色区域”（0.75 - 0.85）的患者中，重复进行FFR评估有时会得出相互矛盾的结果。灰色区域周围FFR值波动的原因之一可能是未能精确识别达到最大充血的点。在FFR评估过程中识别最大充血状态可能具有挑战性。本研究旨在确定无创电动测速法（EV）是否可用于识别最大充血状态。在15例接受FFR评估的患者中，通过EV测定每搏输出量（SV）、SV变异度（SVV）和全身血管阻力指数（SVRI）。确定从开始输注腺苷到达到最大充血（时间）以及达到最大心输出量（CO）、SV、SVV和SVRI（分别为时间、时间、时间和时间）的时间间隔。时间和时间比其他值更接近时间（时间/时间与时间/时间 = 1.03 ± 0.2对1.36 ± 0.4，P < 0.05）。由于变化较大，SV的最大值难以确定，但SVV的最大值清晰可辨。时间和时间与时间显著相关，时间的相关性比时间更强（时间：r = 0.92，P < 0.01；时间：r = 0.80，P < 0.01）。最大SVV在接近最大充血时达到。在FFR评估期间用无创EV监测SVV有助于识别最大充血状态。
