Functional measurements based on feature tracking of cine magnetic resonance images identify left ventricular segments with myocardial scar

Abstract

BackgroundThe aim of the study was to perform a feature tracking analysis on cine magnetic resonance (MR) images to elucidate if functional measurements of the motion of the left ventricular wall may detect scar defined with gadolinium enhanced MR.Myocardial contraction can be measured in terms of the velocity, displacement and local deformation (strain) of a particular myocardial segment. Contraction of the myocardial wall will be reduced in the presence of scar and as a consequence of reduced myocardial blood flow.MethodsThirty patients (3 women and 27 men) were selected based on the presence or absence of extensive scar in the anteroseptal area of the left ventricle. The patients were investigated in stable clinical condition, 4-8 weeks post ST-elevation myocardial infarction treated with percutaneous coronary intervention. Seventeen had a scar area >75% in at least one anteroseptal segment (scar) and thirteen had scar area <1% (non-scar). Velocity, displacement and strain were calculated in the longitudinal direction, tangential to the endocardial outline, and in the radial direction, perpendicular to the tangent.ResultsIn the scar patients, segments with scar showed lower functional measurements than remote segments. Radial measurements of velocity, displacement and strain performed better in terms of receiver-operator-characteristic curves (ROC) than the corresponding longitudinal measurements. The best area-under-curve was for radial strain, 0.89, where a cut-off value of 38.8% had 80% sensitivity and 86% specificity for the detection of a segment with scar area >50%. As a percentage of the mean, intraobserver variability was 16-14-26% for radial measurements of displacement-velocity-strain and corresponding interobserver variability was 13-12-18%.ConclusionFeature tracking analysis of cine-MR displays velocity, displacement and strain in the radial and longitudinal direction and may be used for the detection of transmural scar. The accuracy and repeatability of the radial functional measurements is satisfactory and global measures agree.

Cardiovascular Magnetic Resonance Myocardial Feature Tracking

“…The technique can be applied for the quantification of right and left ventricular (LV) systolic and diastolic function using strain 10,18 and SR 19 imaging as well as myocardial torsion and diastolic recoil quantification. 20,21 The study of atrial physiology using strain and SR imaging has recently been explored.…”

“…The majority of CMR-FT studies have used the Diogenes and Cardiac Performance Analysis-MR software provided by TomTec Imaging systems (TomTec, Unterschleissheim, Germany). 10 Other vendors including Toshiba 11 (Tokyo, Japan) and more recently Circle 12 (Calgary, Canada) have released alternative FT software platforms. The purpose of this article is to summarize the basic principles, evolving clinical applications, accuracy and reproducibility data of CMR-FT.…”

Phase analysis detects heterogeneity of myocardial deformation on cine MRI

“…-16 -shown that measurements of velocity, displacement and peak systolic strain in the radial direction by MRI were able to differentiate segments with varying extent of scar (14). The most accurate information was obtained by measurements of radial strain in that study.…”

Developing advanced mathematical models for detecting abnormalities in 2D/3D medical structures.

“…Most of these methods depend on texture features to track predefined points on the inner and outer LV wall. For example, Maret et al [94] used a feature tracking method to estimate the strain and other indexes from cine CMRI and showed that it can be used for the detection of the transmural scar. Hor et al [95] correlated between the estimated strains from tagged MRI (using HARP method) and from cine CMRI (using tracking) in a population with a wide range of cardiac dysfunction.…”

“…To avoid the inter-slice variability, recent trends estimate the strain from cine CMRI (e.g., [94][95][96][97]). Most of these methods depend on texture features to track predefined points on the inner and outer LV wall.…”