Author + information
- Received December 14, 2017
- Revision received February 5, 2018
- Accepted February 6, 2018
- Published online April 16, 2018.
- Hernán Mejía-Rentería, MDa,
- Joo Myung Lee, MD, MPH, PhDb,
- Francesco Lauri, MDa,
- Nina W. van der Hoeven, MDa,c,
- Guus A. de Waard, MDc,
- Fernando Macaya, MDa,
- María José Pérez-Vizcayno, MDa,
- Nieves Gonzalo, MD, PhDa,
- Pilar Jiménez-Quevedo, MD, PhDa,
- Luis Nombela-Franco, MD, PhDa,
- Pablo Salinas, MD, PhDa,
- Iván Núñez-Gil, MD, PhDa,
- María del Trigo, MD, PhDa,
- Sonoka Goto, MDa,
- Hyun Jong Lee, MDa,
- Catherine Liontou, MDa,
- Antonio Fernández-Ortiz, MD, PhDa,
- Carlos Macaya, MD, PhDa,
- Niels van Royen, MD, PhDc,d,
- Bon-Kwon Koo, MD, PhDe,f and
- Javier Escaned, MD, PhDa,∗ ()
- aDepartment of Cardiology, Hospital Clínico San Carlos IDISSC and Universidad Complutense de Madrid, Madrid, Spain
- bDivision of Cardiology, Department of Internal Medicine, Heart Vascular Stroke Institute, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
- cDepartment of Cardiology, VU University Medical Center, Amsterdam, the Netherlands
- dDepartment of Cardiology, Radboud University Medical Center, the Netherlands
- eDepartment of Internal Medicine and Cardiovascular Center, Seoul National University Hospital, Seoul, Korea
- fInstitute on Aging, Seoul National University, Seoul, Korea
- ↵∗Address for correspondence:
Dr. Javier Escaned, Hospital Clínico San Carlos IDISSC, Calle del Profesor Martín Lagos, S/N, 28040 Madrid, Spain.
Objectives The authors sought to evaluate the influence of coronary microcirculatory dysfunction (CMD) on the diagnostic performance of the quantitative flow ratio (QFR).
Background Functional angiographic assessment of coronary stenoses based on fluid dynamics, such as QFR, constitutes an attractive alternative to fractional flow reserve (FFR). However, it is unknown whether CMD affects the reliability of angiography-based functional indices.
Methods FFR and the index of microcirculatory resistance (IMR) were measured in 300 vessels (248 patients) as part of a multicenter international registry. QFR was calculated at a blinded core laboratory. Vessels were classified into 2 groups according to microcirculatory status: low IMR (<23 U), and high IMR (≥23 U, CMD). The impact of CMD on the diagnostic performance of QFR, as well as on incremental value of QFR over quantitative angiography, was assessed using FFR as reference.
Results Percent diameter stenosis (%DS) and FFR were similar in low- and high-IMR groups (%DS 51 ± 12% vs. 53 ± 11%; p = 0.16; FFR 0.80 ± 0.11 vs. 0.81 ± 0.11; p = 0.23, respectively). In the overall cohort, classification agreement (CA) between QFR and FFR and diagnostic efficiency of QFR (area under the receiver-operating characteristics curve [AUC]) were high (CA: 88%; AUC: 0.93 [95% confidence interval (CI): 0.90 to 0.96]). However, when assessed according to microcirculatory status, a significantly lower CA and AUC of QFR were found in the high-IMR group as compared with the low-IMR group (CA: 76% vs. 92%; p < 0.001; AUC: 0.88 [95% CI: 0.79 to 0.94] vs. 0.96 [95% CI: 0.92 to 0.98]; p < 0.05). Compared with angiographic assessment, QFR increased by 0.20 (p < 0.001) and by 0.16 (p < 0.001) the AUC of %DS in low- and high-IMR groups, respectively. Independent predictors of misclassification between QFR and FFR were high IMR and acute coronary syndrome.
Conclusions CMD decreases the diagnostic performance of QFR. However, even in the presence of CMD, QFR remains superior to angiography alone in ascertaining functional stenosis severity.
- computational fluid dynamics
- fractional flow reserve
- index of microcirculatory resistance
- microcirculatory dysfunction
- quantitative flow ratio
Dr. F. Macaya is supported by Fundación Interhospitalaria para la Investigación Cardiovascular. Drs. J.M. Lee and Koo have received an institutional research grants from St. Jude Medical (Abbott Vascular) and Philips Volcano. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.
- Received December 14, 2017.
- Revision received February 5, 2018.
- Accepted February 6, 2018.
- 2018 American College of Cardiology Foundation
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