Coronary interventions - Mini focus on Coronary Physiology

Reproducibility of quantitative flow ratio: the QREP study

EuroIntervention 2022;17:1252-1259. DOI: 10.4244/EIJ-D-21-00425

Jelmer Westra
Jelmer Westra1, MD; Martin Sejr-Hansen1, BSc; Lukasz Koltowski2, MD; Hernán Mejía-Rentería3, MD; Shengxian Tu4, PhD; Janusz Kochman2, MD; Yimin Zhang4, MSc; Tommy Liu5, MD; Gianluca Campo6, MD; Jakob Hjort1, MPH; Lone Juul Hune Mogensen1, MStat; Andrea Erriquez6, MD; Birgitte Krogsgaard Andersen1, MD; Ashkan Eftekhari1, MD, PhD; Javier Escaned3, MD, PhD; Evald Høj Christiansen1, MD, PhD; Niels Ramsing Holm1, MD
1. Department of Cardiology, Aarhus University Hospital, Skejby, Denmark; 2. Department of Cardiology, Medical University of Warsaw, Warsaw, Poland; 3. Department of Cardiology, Hospital Clinico San Carlos, Madrid, Spain; 4. School of Biomedical Engineering, Shanghai Jiao Tong University, Shanghai, China; 5. Department of Cardiology, Hagaziekenhuis, The Hague, the Netherlands; 6. Cardiology Unit, Azienda Ospedaliera Universitaria di Ferrara, Ferrara, Italy and Maria Cecilia Hospital, GVM Care & Research, Cotignola (RA), Italy

Background: Quantitative flow ratio (QFR) is a tool for physiological lesion assessment based on invasive coronary angiography.

Aims: We aimed to assess the reproducibility of QFR computed from the same angiograms as assessed by multiple observers from different, international sites.

Methods: We included 50 patients previously enrolled in dedicated QFR studies. QFR was computed twice, one month apart by five blinded observers. The main analysis was the coefficient of variation (CV) as a measure of intra- and inter-observer reproducibility. Key secondary analysis was the identification of clinical and procedural characteristics predicting reproducibility.

Results: The intra-observer CV ranged from 2.3% (1.5-2.8) to 10.2% (6.6-12.0) among the observers. The inter-observer CV was 9.4% (8.0-10.5). The QFR observer, low angiographic quality, and low fractional flow reserve (FFR) were independent predictors of a large absolute difference between repeated QFR measurements defined as a difference larger than the median difference (>0.03).

Conclusions: The inter- and intra-observer reproducibility for QFR computed from the same angiograms ranged from high to poor among multiple observers from different sites with an average agreement of 0.01±0.08 for repeated measurements. The reproducibility was dependent on the observer, angiographic quality and the coronary artery stenosis severity as assessed by FFR.

Sign in to read and download the full article

Forgot your password?

No account yet?
Sign up for free!

Create my pcr account

Join us for free and access thousands of articles from EuroIntervention, as well as presentations, videos, cases from PCRonline.com

fractional flow reserveqcastable angina
Read next article
Phasic flow patterns of right versus left coronary arteries in patients undergoing clinical physiological assessment

Latest news