Longitudinal strain with speckle-tracking echocardiography predicts electroanatomic substrate for ventricular tachycardia in nonischemic cardiomyopathy patients

Siddharth J Trivedi; Timothy Campbell; Christopher J Davey; Luke Stefani; Liza Thomas; Saurabh Kumar

doi:10.1016/j.hroo.2022.02.002

Longitudinal strain with speckle-tracking echocardiography predicts electroanatomic substrate for ventricular tachycardia in nonischemic cardiomyopathy patients

Heart Rhythm O2. 2022 Feb 8;3(2):176-185. doi: 10.1016/j.hroo.2022.02.002. eCollection 2022 Apr.

Authors

Siddharth J Trivedi^{1

2}, Timothy Campbell^{1

3}, Christopher J Davey¹, Luke Stefani¹, Liza Thomas^{1

2

4}, Saurabh Kumar^{1

2

3}

Affiliations

¹ Department of Cardiology, Westmead Hospital, Sydney, Australia.
² Westmead Clinical School, The University of Sydney, Sydney, Australia.
³ Westmead Applied Research Centre, The University of Sydney, Sydney, Australia.
⁴ South Western Sydney Clinical School, University of New South Wales, Sydney, Australia.

Abstract

Background: Longitudinal strain (LS) derived from speckle-tracking echocardiography (STE) corresponds to regions of scar in ischemic cardiomyopathy.

Objective: We investigated if regional LS abnormalities correlate with scar location and scar burden, identified using high-density electroanatomic mapping (EAM) in nonischemic cardiomyopathy (NICM).

Methods: Fifty NICM patients with ventricular tachycardia (VT) underwent echocardiography; multilayer (endocardial, midmyocardial, and epicardial) regional LS and global LS (GLS) were evaluated prior to EAM for detection of low-voltage scar. Patients were divided into 3 groups by EAM left ventricular scar location: (1) anteroseptal (group 1, n = 20); (2) inferolateral (group 2, n = 20); and (3) epicardial scar (group 3; n = 10). We correlated (1) location of scar to regional LS and (2) regional strain and GLS to scar percentage.

Results: Regional LS abnormalities correlated with EAM scar in all groups. Segmental impaired LS and low voltage on EAM demonstrated concordance with scar in ∼75% or its border zone in 25% of segments. In groups 1 and 2, endocardial GLS showed a strong linear correlation with endocardial bipolar scar percentage (r = 0.79, 0.75 for groups 1 and 2, respectively; P < .001), whereas midmyocardial GLS correlated with unipolar scar percentage (r = 0.82, 0.78 for groups 1 and 2, respectively; P < .001). In group 3, epicardial regional LS and GLS correlated with epicardial bipolar scar percentage (r = 0.72, P < .001).

Conclusion: Regional abnormalities on LS predict scar location on EAM mapping in patients with NICM. Moreover, global and regional LS correlate with scar percentage. STE could be used as a noninvasive tool for localizing and quantifying scar prior to EAM.

Keywords: Global longitudinal strain; Nonischemic cardiomyopathy; Speckle tracking; Strain echocardiography; Ventricular tachycardia; Voltage mapping.