Background: Coronary lesions with low fractional flow reserve (FFR) that are treated medically are associated with higher revascularization rates. High wall shear stress (WSS) has been linked with increased plaque vulnerability. Objectives: This study investigated the prognostic value of WSS measured in the proximal segments of lesions (WSSprox) to predict myocardial infarction (MI) in patients with stable coronary artery disease (CAD) and hemodynamically significant lesions. The authors hypothesized that in patients with low FFR and stable CAD, higher WSSprox would predict MI. Methods: Among 441 patients in the FAME II (Fractional Flow Reserve Versus Angiography for Multivessel Evaluation II) trial with FFR ≤0.80 who were randomized to medical therapy alone, 34 (8%) had subsequent MI within 3 years. Patients with vessel-related MI and adequate angiograms for 3-dimensional reconstruction (n = 29) were propensity matched to a control group with no MI (n = 29) by using demographic and clinical variables. Coronary lesions were divided into proximal, middle, and distal, along with 5-mm upstream and downstream segments. WSS was calculated for each segment. Results: Median age was 62 years, and 46 (79%) were male. In the marginal Cox model, whereas lower FFR showed a trend (hazard ratio: 0.084; p = 0.064), higher WSSprox (hazard ratio: 1.234; p = 0.002, C-index = 0.65) predicted MI. Adding WSSprox to FFR resulted in a significant increase in global chi-square for predicting MI (p = 0.045), a net reclassification improvement of 0.69 (p = 0.005), and an integrated discrimination index of 0.11 (p = 0.010). Conclusions: In patients with stable CAD and hemodynamically significant lesions, higher WSS in the proximal segments of atherosclerotic lesions is predictive of MI and has incremental prognostic value over FFR.
Bibliographical noteFunding Information:
Dr. Min has been on the scientific advisory boards of Arineta and GE Healthcare; has received funding from Dalio Foundation, National Institutes of Health, and GE Healthcare; and has equity interest in Cleerly. Dr. Fearon has received research support from Abbott, Medtronic, and CathWorks; and has been a consultant for Boston Scientific and HeartFlow. Dr. King serves on the data safety monitoring board for trials sponsored by Stentys, Capricor, Cardiovascular Research Foundation, Mt. Sinai School of Medicine, Merck, and Baim Institute for Clinical Research. Dr. De Bruyne is a shareholder of Siemens, GE Healthcare, Bayer, Philips, HeartFlow, Edwards Lifesciences, and Sanofi; his institution has received grant support from Abbott, Boston Scientific, Biotronik, and St. Jude Medical; and receives consulting fees on his behalf from St. Jude Medical, Opsens, and Boston Scientific. Dr. Samady has received research grants from Abbott Vascular, Medtronic, National Institutes of Health, St. Jude Medical, and Gilead. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.
© 2018 American College of Cardiology Foundation
All Science Journal Classification (ASJC) codes
- Cardiology and Cardiovascular Medicine