Evaluating the role of left ventricle global longitudinal strain in myocardial viability assessment

Background: Evaluation of myocardial tissue viability, most commonly performed with single photon emission computed tomography (SPECT), is useful for patient prognosis, management and risk stratification. Two-dimensional speckle tracking echocardiography (2D-STE) and specifically left ventricle (LV) Global Longitudinal Strain (GLS) has gained interest for observing subclinical LV dysfunction. We aimed to investigate the utility of LV GLS for the evaluation of myocardial tissue viability.

Methods: A retrospective study was conducted, including all patients who underwent SPECT and LV GLS at Tel Aviv Sourasky medical center up to 1-year apart, without coronary interventions in-between. Comparisons of reversible and fixed defects were made by myocardial sections, and by arterial supply territory.

Results: Eighty-six patients were included, 32 (37%) were female and the mean age was 70(±13) years. LV GLS and SPECT correlated in all myocardial sections and in the RCA and LAD territories for fixed defects, and in the apex only for reversible defects. Adjusted analyses showed significant associations in the apex for both reversible and fixed defects, and in the mid-section for fixed defects, while no associations were found by arterial supply territory. A sub-analysis of patients without left bundle branch block (LBBB) strengthened the correlations, with a 58% to 70% higher chance of both fixed and reversible defects for every 1-unit decrease LV GLS in the mid and apical sections.

Conclusions: LV GLS effectively evaluated the presence of infraction by SPECT in the mid and apical sections, particularly in patients without LBBB. Due to its increased availability and ease of use, LV GLS may have a role in the evaluation of tissue viability following myocardial injury.