Fractional Flow Reserve Returns to Its Origins by Nils P. Johnson, and K. Lance Gould Circ Cardiovasc Imaging Volume 9(9):e005435 September 8, 2016 Copyright © American Heart Association, Inc. All rights reserved.

Relationship between positron emission tomography (PET)–derived relative flow reserve (RFR) and invasive fractional flow reserve (FFR). Relationship between positron emission tomography (PET)–derived relative flow reserve (RFR) and invasive fractional flow reserve (FFR). By design, a highly linear relationship exists between PET-derived RFR and invasive FFR, as summarized by 4 publications >22 years containing 448 lesions in 271 subjects. A, Figure 3A with 92 lesions in 92 subjects. Reprinted from Stuijfzand et al10 with permission of the publisher. Copyright ©2015, Wolters Kluwer Health, Inc. B, Figure 1A with 27 lesions in 27 subjects. Reprinted from Marques et al18 with permission of the publisher. Copyright ©2007, the Society of Nuclear Medicine and Molecular Imaging, Inc. C, Figure 4A with 22 lesions in 22 subjects. Reprinted from De Bruyne et al2 with permission of the publisher. Copyright ©1994, Wolters Kluwer Health, Inc. D, Figure 1C with 307 lesions in 130 subjects. Reprinted from Lee et al7 with permission of the publisher. Copyright ©2016, Wolters Kluwer Health, Inc. Nils P. Johnson, and K. Lance Gould Circ Cardiovasc Imaging. 2016;9:e005435 Copyright © American Heart Association, Inc. All rights reserved.

Relationship between coronary or myocardial flow reserve (CFR or MFR) and invasive fractional flow reserve (FFR). Relationship between coronary or myocardial flow reserve (CFR or MFR) and invasive fractional flow reserve (FFR). A triangular relationship exists between CFR and invasive FFR, as summarized here in 1199 lesions from 489 subjects using cardiac PET but also seen using every other tool to assess flow reserve. A, Conceptual Figure 3 describes the mechanisms for CFR vs FFR discordance. Reprinted from Johnson et al11 with permission of the publisher. Copyright ©2012, Elsevier. B, Figure 7C with 863 lesions in 330 subjects. Reprinted from Danad et al19 with permission of the publisher. Copyright ©2014, Elsevier. C, Figure 4D with 29 lesions in 29 subjects. Reprinted from Valenta et al20 with permission of the publisher. Copyright ©2016, Oxford University Press. D, Figure 1A with 307 lesions in 130 subjects. Reprinted from Lee et al7 with permission of the publisher. Copyright ©2016, Wolters Kluwer Health, Inc. Nils P. Johnson, and K. Lance Gould Circ Cardiovasc Imaging. 2016;9:e005435 Copyright © American Heart Association, Inc. All rights reserved.