Author + information
- Kenichiro Otsuka, MD, PhDa,
- Martin Villiger, PhDa,
- Antonios Karanasos, MD, PhDb,c,
- Laurens J.C. van Zandvoort, BScb,
- Pallavi Doradla, PhDa,
- Jian Ren, PhDa,
- Norman Lippok, PhDa,
- Joost Daemen, MD, PhDb,
- Roberto Diletti, MD, PhDb,
- Robert-Jan van Geuns, MD, PhDb,d,
- Felix Zijlstra, MD, PhDb,
- Gijs van Soest, PhDb,
- Jouke Dijkstra, PhDe,
- Seemantini K. Nadkarni, PhDa,
- Evelyn Regar, MD, PhDb,f and
- Brett E. Bouma, PhDa,b,g,∗ ()
- aWellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, Boston, Massachusetts
- bDepartment of Cardiology, Thoraxcenter, Erasmus University Medical Center, Rotterdam, the Netherlands
- c1st Department of Cardiology, Hippokration Hospital, University of Athens, Athens, Greece
- dDepartment of Cardiology of Radboud UMC, Nijmegen, the Netherlands
- eDivision of Image Processing, Department of Radiology, Leiden University Medical Center, Leiden, the Netherlands
- fHeart Center, University Hospital Zurich, Zurich, Switzerland
- gInstitute for Medical Engineering and Science, Massachusetts Institute of Technology, Cambridge, Massachusetts
- ↵∗Address for correspondence:
Dr. Brett E. Bouma, Wellman Center for Photomedicine, Massachusetts General Hospital, Harvard Medical School, 50 Blossom Street, Boston, Massachusetts 02114.
Objectives The aims of this first-in-human pilot study of intravascular polarimetry were to investigate polarization properties of coronary plaques in patients and to examine the relationship of these features with established structural characteristics available to conventional optical frequency domain imaging (OFDI) and with clinical presentation.
Background Polarization-sensitive OFDI measures birefringence and depolarization of tissue together with conventional cross-sectional optical frequency domain images of subsurface microstructure.
Methods Thirty patients undergoing polarization-sensitive OFDI (acute coronary syndrome, n = 12; stable angina pectoris, n = 18) participated in this study. Three hundred forty-two cross-sectional images evenly distributed along all imaged coronary arteries were classified into 1 of 7 plaque categories according to conventional OFDI. Polarization features averaged over the entire intimal area of each cross section were compared among plaque types and with structural parameters. Furthermore, the polarization properties in cross sections (n = 244) of the fibrous caps of acute coronary syndrome and stable angina pectoris culprit lesions were assessed and compared with structural features using a generalized linear model.
Results The median birefringence and depolarization showed statistically significant differences among plaque types (p < 0.001 for both, 1-way analysis of variance). Depolarization differed significantly among individual plaque types (p < 0.05), except between normal arteries and fibrous plaques and between fibrofatty and fibrocalcified plaques. Caps of acute coronary syndrome lesions and ruptured caps exhibited lower birefringence than caps of stable angina pectoris lesions (p < 0.01). In addition to clinical presentation, cap birefringence was also associated with macrophage accumulation as assessed using normalized standard deviation.
Conclusions Intravascular polarimetry provides quantitative metrics that help characterize coronary arterial tissues and may offer refined insight into coronary arterial atherosclerotic lesions in patients.
This work was supported by the National Institutes of Health (grants P41EB-015903 and R01HL-119065) and by Terumo Corporation. Dr. Bouma was supported in part by the Professor Andries Querido visiting professorship of the Erasmus University Medical Center in Rotterdam. Dr. Otsuka acknowledges partial support from the Japan Heart Foundation/Bayer Yakuhin Research Grant Abroad, the Uehara Memorial Foundation Postdoctoral Fellowship, and the Japan Society for the Promotion of Science Overseas Research Fellowship. Massachusetts General Hospital and the Erasmus University Medical Center have patent licensing arrangements with Terumo Corporation. Drs. Bouma, van Soest, and Villiger have the right to receive royalties as part of the licensing arrangements. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose.
- Received January 22, 2019.
- Revision received April 24, 2019.
- Accepted June 11, 2019.
- 2019 The Authors