Fractional flow reserve-guided percutaneous coronary intervention: where to after FAME 2?

Abstract

Fractional flow reserve (FFR) is a well-validated clinical coronary physiological parameter derived from the measurement of coronary pressures and has drastically changed revascularization decision-making in clinical practice. Nonetheless, it is important to realize that FFR is a coronary pressure-derived estimate of coronary blood flow impairment. It is thereby not the same as direct measures of coronary flow impairment that determine the occurrence of signs and symptoms of myocardial ischemia. This consideration is important, since the FAME 2 study documented a limited discriminatory power of FFR to identify stenoses that require revascularization to prevent adverse events. The physiological difference between FFR and direct measures of coronary flow impairment may well explain the findings in FAME 2. This review aims to address the physiological background of FFR, its ambiguities, and its consequences for the application of FFR in clinical practice, as well as to reinterpret the diagnostic and prognostic characteristics of FFR in the light of the recent FAME 2 trial outcomes.

Keywords:

• fractional flow reserve
• coronary flow
• stable ischemic heart disease

Disclosure

Dr van de Hoef has served as a speaker at educational events organized by Volcano Corporation, St Jude Medical, and Boston Scientific, manufacturers of sensor-equipped guide wires. Drs Meuwissen and Piek have served as speakers at educational events organized by Volcano Corporation. The authors report no other conflicts of interest in this work.