Global longitudinal strain
Echocardiographic parameter measuring the percentage change in myocardial fiber length during systole, providing sensitive assessment of left ventricular function.
Full Definition
Global longitudinal strain (GLS) is an advanced echocardiographic parameter that quantifies the average deformation of myocardial fibers in the longitudinal direction during systolic contraction. Measured using speckle-tracking echocardiography, GLS represents the percentage change in fiber length from end-diastole to end-systole across all left ventricular segments. This parameter is more sensitive than ejection fraction for detecting early myocardial dysfunction and is particularly valuable in cardio-oncology monitoring, heart failure assessment, and valvular heart disease evaluation. Normal GLS values are typically more negative than -18%, with less negative values indicating impaired myocardial function.
Usage
Usage note: Express as a negative percentage (e.g., -16%); more negative values indicate better function, less negative values indicate dysfunction.
In Context
- "Despite preserved LVEF of 55%, the global longitudinal strain was reduced at -14%, suggesting subclinical dysfunction." — Advanced echocardiography report
- "Global longitudinal strain monitoring revealed early cardiotoxicity before changes in ejection fraction became apparent." — Cardio-oncology surveillance study