Percutaneous Coronary Intervention Should Be Guided by Fractional Flow Reserve MeasurementResponse to Fearon
The importance of integrating coronary physiology into percutaneous coronary intervention (PCI) has been recognized since its inception. When Andreus Gruentzig first described percutaneous transluminal coronary angioplasty, he stressed the need to identify the translesional pressure gradient before and after intervention as a means of guiding a successful procedure.1 Subsequently, other investigators examined the use of the Doppler wire to measure coronary flow velocity reserve before and after PCI.2 Unfortunately, the lack of a low-profile pressure-monitoring device and the lack of appreciation of the importance of measuring hyperemic pressure gradients inhibited the full integration of coronary physiology into the PCI procedure. Additionally, with the advent of stents, the ease and safety of PCI improved dramatically. In conjunction with financial reimbursement for PCI and patient demand, these factors resulted in an inclination toward performing PCI, regardless of the functional significance of the stenosis.
Response by Arbab-Zadeh p 1870
While this enthusiasm over PCI was occurring, Pijls and coworkers3 and De Bruyne and colleagues4 first described fractional flow reserve (FFR). Like any new technique, FFR has required time to mature. Over the ensuing 20 years since its introduction, improvements in the pressure wire–handling characteristics, the integration of data acquisition into the catheterization laboratory workflow, the completion of a number of multicenter, randomized studies, and the increased emphasis on appropriate use of PCI have contributed to FFR achieving its current status as an indispensable and critical component of PCI.
Concept of FFR
FFR is defined as the ratio of myocardial blood flow down a coronary artery in the presence of an epicardial stenosis compared with the flow down the same vessel in the theoretical absence of any stenosis.3 The derivation of FFR has been described in detail and is shown in brief in Figure 1.3,4 FFR can be …