Principles of cardiovascular magnetic resonance feature tracking and echocardiographic speckle tracking for informed clinical use

Abstract

Tissue tracking technology of routinely acquired cardiovascular magnetic resonance (CMR) cine acquisitions has increased the apparent ease and availability of non-invasive assessments of myocardial deformation in clinical research and practice. Its widespread availability thanks to the fact that this technology can in principle be applied on images that are part of every CMR or echocardiographic protocol. However, the two modalities are based on very different methods of image acquisition and reconstruction, each with their respective strengths and limitations. The image tracking methods applied are not necessarily directly comparable between the modalities, or with those based on dedicated CMR acquisitions for strain measurement such as tagging or displacement encoding. Here we describe the principles underlying the image tracking methods for CMR and echocardiography, and the translation of the resulting tracking estimates into parameters suited to describe myocardial mechanics. Technical limitations are presented with the objective of suggesting potential solutions that may allow informed and appropriate use in clinical applications.

Magnetic Resonance Imaging of Myocardial Deformation and Scarring in Coronary Artery Disease.

“…Similar results have been presented by other authors using DENSE in suspected CAD [145] and in acute myocardial infarction [146]. Longitudinal strain is often used in echocardiography [65], because echo works well in apical views but not at all in SA views [46].…”

“…After the injection of Gd contrast, delayed imaging shows the size of the infarct scar [45], which is of major prognostic importance [23]. Furthermore, CMR has the advantage of a wide coverage such that the entire heart can be depicted, which is difficult to achieve with echocardiography [46].…”

“…The technique identifies image features, such as variation in the tissue signal in relation to 48 points along the myocardial boundaries, which are followed throughout the cardiac cycle [81]. No additional imaging is required, but the disadvantage is that through-plane displacement of the tissue could confuse the algorithm [46].…”

Recent Advances in Cardiovascular Magnetic Resonance

“…New techniques, such as displacement encoding with stimulated echoes (DENSE) 72 and feature tracking from cine imaging, are bringing CMR strain techniques into routine clinical practice. 73 Another area of active research is improving CMR imaging in the presence of cardiac devices. New techniques, such as wideband late gadolinium–enhanced, are extending the utility of CMR to the growing number of patients with implantable cardiac devices.…”

Association of Feature-Tracking Cardiac Magnetic Resonance Imaging Left Ventricular Global Longitudinal Strain With All-Cause Mortality in Patients With Reduced Left Ventricular Ejection Fraction

“…Recent development of CMR feature-tracking techniques now allow assessment of GLS from standard cine CMR images without the need for specialized pulse sequences or additional scanning time 2 . We therefore hypothesized that CMR feature-tracking derived GLS may provide incremental prognostic information in these patients.…”