Regional myocardial strain measurements from 4DCT in patients with normal LV function

• Type of Material: Article
• Authors: Elliot R. McVeigh, University of California San Diego; Amir Pourmorteza, Emory University; Michael Guttman, Johns Hopkins University; Veit Sandfort, University of California San Diego; Francisco Contijoch, University of California San Diego; Suhas Budhiraja, University of California San Diego; Zhennong Chen, University of California San Diego; David A. Bluemke, University of Wisconsin Madison; Marcus Y. Chen, National Heart, Lung, and Blood Institute
• Language: English
• Date: 2018-09-01
• Publisher: Elsevier Science Inc.
• Publication Version: Author Accepted Manuscript (After Peer Review)
• Copyright Statement: © 2018 Published by Elsevier Inc. All rights reserved.
• License: Creative Commons Attribution-NonCommercial-NoDerivs 4.0 International
• Final Published Version (URL): http://dx.doi.org/10.1016/j.jcct.2018.05.002
• Title of Journal or Parent Work: Journal of Cardiovascular Computed Tomography
• Volume: 12
• Issue: 5
• Start Page: 372
• End Page: 378
• Grant/Funding Information: This work received support from: UC San Diego Frontiers of Innovation Scholars Program (ERM), University of California President’s Postdoctoral Fellowship Program (FC).
• Keywords: Regional myocardial function; Science & Technology; Radiology, Nuclear Medicine & Medical Imaging; Adult congenital heart; MDCT; Myocardial strain; Romicat trial; Coronary artery disease; Left ventricular strain; CT; Cardiac CT; Myocardial contraction; Reference values; Speckle tracking echocardiography; Cardiac computed tomography; Magnetic resonance; Acute chest pain; Life Sciences & Biomedicine; Cardiovascular System & Cardiology; Cardiac & Cardiovascular Systems
• Research Categories: Health Sciences, Radiology; Engineering, Biomedical; Health Sciences, Oncology

Abstract

Background: CT SQUEEZ is a new automated technique to evaluate regional endocardial strain by tracking features on the endocardium from 4D cine CT data. The objective of this study was to measure the range of endocardial regional strain (RSCT) values obtained with CT SQUEEZ in the normal human left ventricle (LV) from standard clinical 4D coronary CTA exams. Methods: RSCT was measured over the heart cycle in 25 humans with normal LV function using cine CT from three vendors. Mean and standard deviation of RSCT values were computed in 16 AHA LV segments to estimate the range of values expected in the normal LV. Results: Curves describing RSCT vs. time were consistent between subjects. There was a slight gradient of decreasing minimum RSCT value (increased shortening) from the base to the apex of the heart. Mean RSCT values at end-systole were: base = −32% ± 1%, mid = −33% ± 1%, apex = −36% ± 1%. The standard deviation of the minimum systolic RSCT in each segment over all subjects was 5%. The average time to reach maximum shortening was 34% of the RR interval. Conclusions: Regional strain (RSCT) can be rapidly obtained from standard gated coronary CCTA protocols using 4DCT SQUEEZ processing. We estimate that 95% of normal LV end-systolic RSCT values will fall between −23% and −43%; therefore, we hypothesize that an RSCT value higher than −23% will indicate a hypokinetic segment in the human heart.