Standardized hyperemic stress for fractional flow reserve.

Change in coronary blood flow after percutaneous coronary intervention in relation to baseline lesion physiology: results of the JUSTIFY-PCI study.

BACKGROUND Percutaneous coronary intervention (PCI) aims to increase coronary blood flow by relieving epicardial obstruction. However, no study has objectively confirmed this and assessed changes in flow over different phases of the cardiac cycle. We quantified the change in resting and hyperemic flow velocity after PCI in stenoses defined physiologically by fractional flow reserve and other pa...

Magnetic Resonance for Noninvasive Detection of Microcirculatory Disease Associated With Allograft Vasculopathy: Intracoronary Measurement Validation.

INTRODUCTION AND OBJECTIVES Cardiac allograft vasculopathy affects both epicardial and microcirculatory coronary compartments. Magnetic resonance perfusion imaging has been proposed as a useful tool to assess microcirculation mostly outside the heart transplantation setting. Instantaneous hyperemic diastolic flow velocity-pressure slope, an intracoronary physiology index, has demonstrated a bet...

Reconciling poststenotic pressure with hyperemic flow: comparing coronary flow reserve, instantaneous wave-free ratio, and fractional flow reserve.

Relative flow reserve derived from quantitative perfusion imaging may not outperform stress myocardial blood flow for identification of hemodynamically significant coronary artery disease.

BACKGROUND Quantitative myocardial perfusion imaging is increasingly used for the diagnosis of coronary artery disease. Quantitative perfusion imaging allows to noninvasively calculate fractional flow reserve (FFR). This so-called relative flow reserve (RFR) is defined as the ratio of hyperemic myocardial blood flow (MBF) in a stenotic area to hyperemic MBF in a normal perfused area. The aim of...

End-diastolic fractional flow reserve: comparison with conventional full-cardiac cycle fractional flow reserve.

BACKGROUND Diastolic fractional flow reserve (dFFR) has been shown to be highly sensitive for detection of inducible myocardial ischemia. However, its reliance on measurement of left-ventricular pressure for zero-flow pressure correction, as well as manual extraction of the diastolic interval, has been its major limitation. Given previous reports of minimal zero-flow pressure at end-diastole, w...