Ultrasound Elastography for Biomedical Applications and Medicine

33 Cardiovascular Application of Shear Wave Elastography

Pengfei Song and Shigao Chen

Department of Radiology, Mayo Clinic, Rochester, MN, USA

33.1 Introduction

Cardiovascular diseases cause 17.3 million deaths a year worldwide, according to the World Heart Federation, and are the leading causes of death in the United States, claiming more lives than all forms of cancer combined [1]. Echocardiography has been playing a significant role in diagnosis and prognosis of cardiovascular diseases, thanks to its high imaging frame rate, low cost, and powerful imaging tools such as Doppler blood flow imaging and strain imaging. As evidenced by the success of strain imaging in cardiovascular applications, biomechanical properties of the myocardium and vessels are strong biomarkers for the state of the cardiovascular health [2]. Strain imaging directly measures the dynamic deformation of the tissue, and provides semi‐quantitative assessment of myocardial and vascular stiffness in terms of strain or strain rate [3]. For instance, the ischemic infarcted myocardium contracts less than the normal myocardium and thus exhibits lower strain in strain maps [4]; fatty plaque tissue is softer than fibrous plaque tissue and therefore is represented as regions with higher strain. The main drawback of strain imaging, however, is the unknown stress field within cardiac or vascular walls, which makes quantitative assessment of cardiovascular stiffness challenging.

In the last decade, significant ...