Article Text

Download PDFPDF

Original research
Left ventricular global strains by linear measurements in three dimensions: interrelations and relations to age, gender and body size in the HUNT Study
  1. Asbjørn Støylen1,2,
  2. Harald Edvard Mølmen3,4 and
  3. Håvard Dalen5,6
  1. 1Faculty of Medicine, Department of Circulation and Medical Imaging, NTNU, Norwegian University of Science and Technology, Trondheim, Norway
  2. 2Cardiology, St Olav University Hospital, Trondheim, Norway
  3. 3Asgardstrand General Practice, Horten, Norway
  4. 4Division of Medicine, Department of Endocrinology, Morbid Obesity Centre, Vestfold Hospital Trust, Tonsberg, Norway
  5. 5MI Lab and Department of Circulation and Medical Imaging, NTNU, Trondheim, Norway
  6. 6Cardiology, Levanger Hospital, Levanger, Norway
  1. Correspondence to Professor Asbjørn Støylen; asbjorn.stoylen{at}ntnu.no

Abstract

Background Strain is a relative deformation and has three dimensions, in the left ventricle (LV) usually longitudinal (εL), transmural (εT) and circumferential (εC) strain. All three components can be measured generically by the basic systolic and diastolic dimension measures of LV wall length, wall thickness and diameter. In this observational study we aimed to study the relations of normal generic strains to age, body size and gender, as well as the interrelations between the three strain components.

Methods Generic strains derived from dimension measures by longitudinal and cross-sectional M-mode in all three dimensions were measured in 1266 individuals without heart disease from the Nord-Trøndelag Health Study.

Results The mean εL was −16.3%, εC was −22.7% and εT was 56.5%. Normal values by age and gender are provided. There was a gradient of εC from the endocardial, via the midwall to the external level, lowest at the external. All strains decreased in absolute values by increasing body surface area (BSA) and age, relations were strongest for εL. Gender differences were mainly a function of BSA differences. The three strain components were strongly interrelated through myocardial incompressibility.

Conclusions Global systolic strain is the total deformation of the myocardium; the three strain components are the spatial coordinates of this deformation, irrespective of the technology used for measurement. Normal values are method-dependent and not normative across methods. Interrelation of strains indicates a high degree of myocardial incompressibility and that longitudinal strain carries most of the total information.

  • cardiac function
  • echocardiography
  • epidemiology

This is an open access article distributed in accordance with the Creative Commons Attribution Non Commercial (CC BY-NC 4.0) license, which permits others to distribute, remix, adapt, build upon this work non-commercially, and license their derivative works on different terms, provided the original work is properly cited, appropriate credit is given, any changes made indicated, and the use is non-commercial. See: http://creativecommons.org/licenses/by-nc/4.0/.

View Full Text

Statistics from Altmetric.com

Footnotes

  • Twitter @strain_rate

  • Contributors AS and HD participated in the study design. HD has done the actual acquisitions. HD and HEM have done the measurements. AS has done the data analysis, interpretation and draft of the paper. All three authors participated in critical revision and approved the final manuscript. All authors accept responsibility for the final content.

  • Funding The study was fully sponsored by the Norwegian University of Science and Technology as a PhD grant, as well as the HUNT Study providing the infrastructure for the echocardiography in the HUNT3 Study.

  • Competing interests None declared.

  • Patient consent for publication Not required.

  • Ethics approval All subjects gave written consent to participate in the study and the study was approved by the ethical committee.

  • Provenance and peer review Not commissioned; externally peer reviewed.

  • Data availability statement Data are available upon reasonable request.

Request Permissions

If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.