GLS Clinical Applications — EECC MCQ

Correct answer: A — GLS detects subclinical LV systolic dysfunction before LVEF declines — GLS <-18% (less negative = worse) is abnormal and predicts future HF, CV events, and mortality even when LVEF is preserved; it is more sensitive and reproducible than LVEF for detecting early myocardial disease

Global longitudinal strain (GLS) measures the percentage of myocardial shortening in the longitudinal axis using speckle-tracking echocardiography. Normal GLS: -18% to -22% (more negative = better function). GLS advantages over LVEF: (1) detects subclinical dysfunction before LVEF drops — LVEF is maintained by compensatory mechanisms (increased radial/circumferential function) until decompensation; (2) less load-dependent and more reproducible than LVEF; (3) prognostic value incremental to LVEF. Clinical applications per ESC/EACVI guidelines: (1) chemotherapy cardiotoxicity monitoring (>15% relative GLS decline triggers cardioprotective therapy); (2) subclinical disease detection in: AS (GLS may indicate occult LV dysfunction despite preserved LVEF), amyloidosis (apical sparing pattern = pathognomonic), HCM, HFpEF; (3) prognosis in ACS, HFrEF, HFpEF. This patient's GLS -15% with LVEF 58% indicates subclinical LV disease warranting investigation.

Reference: ASE/EACVI Strain Imaging; ESC Echo Guidelines