Imperial College London, London, United Kingdom.
Cardiovascular Institute, Hospital Clínico San Carlos, Madrid, Spain.
JACC Cardiovasc Interv. 2014 Dec;7(12):1386-96. doi: 10.1016/j.jcin.2014.06.015. Epub 2014 Nov 20.
The aim of this study was to perform hemodynamic mapping of the entire vessel using motorized pullback of a pressure guidewire with continuous instantaneous wave-free ratio (iFR) measurement.
Serial stenoses or diffuse vessel narrowing hamper pressure wire-guided management of coronary stenoses. Characterization of functional relevance of individual stenoses or narrowed segments constitutes an unmet need in ischemia-driven percutaneous revascularization.
The study was performed in 32 coronary arteries with tandem and/or diffusely diseased vessels. An automated iFR physiological map, integrating pullback speed and physiological information, was built using dedicated software to calculate physiological stenosis severity, length, and intensity (ΔiFR/mm). This map was used to predict the best-case post-percutaneous coronary intervention (PCI) iFR (iFRexp) according to the stented location, and this was compared with the observed iFR post-PCI (iFRobs).
After successful PCI, the mean difference between iFRexp and iFRobs was small (mean difference: 0.016 ± 0.004) with a strong relationship between ΔiFRexp and ΔiFRobs (r = 0.97, p < 0.001). By identifying differing iFR intensities, it was possible to identify functional stenosis length and quantify the contribution of each individual stenosis or narrowed segment to overall vessel stenotic burden. Physiological lesion length was shorter than anatomic length (12.6 ± 1.5 vs. 23.3 ± 1.3, p < 0.001), and targeting regions with the highest iFR intensity predicted significant improvement post-PCI (r = 0.86, p < 0.001).
iFR measurements during continuous resting pressure wire pullback provide a physiological map of the entire coronary vessel. Before a PCI, the iFR pullback can predict the hemodynamic consequences of stenting specific stenoses and thereby may facilitate the intervention and stenting strategy.
本研究旨在使用压力导丝的电动回撤进行整个血管的血流动力学绘图，并连续进行瞬时无波比（iFR）测量。
串联和/或弥漫性狭窄会阻碍压力导丝引导的冠状动脉狭窄管理。个体狭窄或狭窄节段的功能相关性的特征是缺血驱动的经皮血运重建中的未满足需求。
该研究在 32 条串联和/或弥漫性病变的冠状动脉中进行。使用专用软件构建自动 iFR 生理图谱，整合回撤速度和生理信息，以计算生理狭窄严重程度、长度和强度（ΔiFR/mm）。该图谱用于根据支架位置预测最佳的经皮冠状动脉介入治疗（PCI）后 iFR（iFRexp），并与 PCI 后观察到的 iFR（iFRobs）进行比较。
在成功 PCI 后，iFRexp 与 iFRobs 之间的平均差异较小（平均差异：0.016 ± 0.004），且ΔiFRexp 与ΔiFRobs 之间具有很强的相关性（r = 0.97，p < 0.001）。通过识别不同的 iFR 强度，可以确定功能狭窄长度，并量化每个狭窄或狭窄节段对整体血管狭窄负担的贡献。生理病变长度短于解剖长度（12.6 ± 1.5 与 23.3 ± 1.3，p < 0.001），针对 iFR 强度最高的区域进行靶向治疗可预测 PCI 后显著改善（r = 0.86，p < 0.001）。
在连续静息压力导丝回撤期间进行 iFR 测量可提供整个冠状动脉的生理图谱。在 PCI 之前，iFR 回撤可以预测特定狭窄部位的血运重建的血流动力学后果，从而可能有助于干预和支架策略。
