Author + information
- Received January 22, 2018
- Revision received May 16, 2018
- Accepted May 24, 2018
- Published online July 18, 2018.
- Hooman Bakhshi, MDa,
- Zahra Meyghani, MDa,
- Satoru Kishi, MDa,
- Tiago A. Magalhães, MDb,c,
- Andrea Vavere, MPHd,
- Pieter H. Kitslaar, MSce,
- Richard T. George, MDd,
- Hiroyuki Niinuma, MD, PhDf,
- Johan H.C. Reiber, PhDe,
- Aisha Betoko, PhDg,
- Matthew Matheson, MSg,
- Carlos E. Rochitte, MDc,
- Marcelo F. Di Carli, MDh,
- Christopher Cox, PhDg,
- João A.C. Lima, MDa and
- Armin Arbab-Zadeh, MD, PhD, MPHa,∗ ()
- aDepartment of Medicine, Division of Cardiology, Johns Hopkins University, Baltimore, Maryland
- bUniversidade Federal do Paraná, Curitiba, Brazil
- cHeart Institute (InCor), University of São Paulo, São Paulo, Brazil
- dMedImmune, Gaithersburg, Maryland
- eDepartment of Radiology, Leiden University/Medical Imaging Systems, Leiden, the Netherlands
- fDivision of Cardiology, St. Luke’s International Hospital, Tokyo, Japan
- gDepartment of Epidemiology, Johns Hopkins University, Baltimore, Maryland
- hDepartment of Radiology, Brigham and Women's Hospital, Boston, Massachusetts
- ↵∗Address for correspondence:
Dr. Armin A. Zadeh, Johns Hopkins University School of Medicine, Division of Cardiology, 600 North Wolfe Street, Blalock 524, Baltimore, Maryland 21287-8222.
Objectives This study sought to investigate the performance of various cardiac computed tomography (CT)–derived atherosclerotic plaque metrics for predicting provocable myocardial ischemia.
Background The association of coronary arterial diameter stenosis with myocardial ischemia is only modest, but cardiac CT provides several other, readily available atherosclerosis metrics, which may have incremental value.
Methods The study analyzed 873 nonstented coronary arteries and their myocardial perfusion territories in 356 patients (mean 62 years of age) enrolled in the CORE320 (Coronary Artery Evaluation using 320-row Multidetector Computed Tomography Angiography and Myocardial Perfusion) study. Myocardial perfusion defects in static CT perfusion imaging were graded at rest and after adenosine in 13 myocardial segments using a 4-point scale. The summed difference score was calculated by subtracting the summed rest score from the summed stress score. Reversible ischemia was defined as summed difference score ≥1. In a sensitivity analysis, results were also provided using single-photon emission computed tomography (SPECT) as the reference standard. Vessel based predictor variables included maximum percent diameter stenosis, lesion length, coronary calcium score, maximum cross-sectional calcium arc, percent atheroma volume (PAV), low-attenuation atheroma volume, positive (external) vascular remodeling, and subjective impression of “vulnerable plaque.” The study used logistic regression models to assess the association of plaque metrics with myocardial ischemia.
Results In univariate analysis, all plaque metrics were associated with reversible ischemia. In the adjusted logistic model, only maximum percent diameter stenosis (1.26; 95% confidence interval: 1.15 to 1.38) remained an independent predictor. With SPECT as outcome variable, PAV and “vulnerable” plaque remained predictive after adjustment. In vessels with intermediate stenosis (40% to 70%), no single metric had clinically meaningful incremental value.
Conclusions Various plaque metrics obtained by cardiac CT predict provocable myocardial ischemia by CT perfusion imaging through their association with maximum percent stenosis, while none had significant incremental value. With SPECT as reference standard, PAV and “vulnerable plaque” remained predictors of ischemia after adjustment but the predictive value added to stenosis assessment alone was small.
The sponsor of the CORE320 study, Canon Medical (formerly Toshiba Medical Systems Corporation), was not involved during any stage of the planning, design, data acquisition, data analysis, or manuscript preparation of this study. Ms. Vavere is an employee with MedImmune. Dr. Kitslaar has a research appointment at the Leiden University Medical Center, Division of Image Processing, Department of Radiology; and is an employee of MEDIS (Leiden, the Netherlands). Dr. George has received grant support from Canon (formerly Toshiba) Medical Systems; has served as a consultant for ICON Medical Imaging; and is an employee of MedImmune. Dr. Reiber is CEO of MEDIS medical imaging systems (Leiden, the Netherlands). Dr. Lima has received grant support from Canon (formerly Toshiba) Medical Systems. Dr. Arbab-Zadeh has served on the CORE320 steering committee. All other authors have reported that they have no relationships relevant to the contents of this paper to disclose. Drs. Bakhshi, Meyghani, and Kishi contributed equally to this work, and are joint first authors.
- Received January 22, 2018.
- Revision received May 16, 2018.
- Accepted May 24, 2018.
- 2018 American College of Cardiology Foundation
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