Reference change value of global longitudinal strain in clinical practice: A test-rest quality implementation project

Area of Science:

• Cardiology
• Medical Imaging
• Biostatistics

Background:

• Reference change value (RCV) assesses measurement significance by accounting for variability.
• Global longitudinal strain (GLS) is a key echocardiographic parameter for cardiac assessment.
• Defining RCV for GLS is crucial for accurate interpretation in clinical practice.

Purpose of the Study:

• To establish the reference change value (RCV) for global longitudinal strain (GLS).
• To compare the performance of semi-automated software (AutoStrain vs. aCMQ) for GLS quantification.
• To identify factors influencing measurement variability in GLS.

Main Methods:

• Test-retest study design to quantify coefficient of variation (CV) for GLS.
• Utilized AutoStrain and aCMQ software for GLS analysis.
• Multivariable regression to identify factors affecting CV, including image quality and wall motion abnormalities (WMA).

Main Results:

• AutoStrain demonstrated higher time efficiency and lower total median CV (7.4%) compared to aCMQ (17.6%).
• Higher total CV was observed in patients with WMA.
• A 15% RCV for GLS was derived, corresponding to 80% probability of real change in non-segmental disease.

Conclusions:

• An RCV of 15% for GLS is an optimistic estimate in routine clinical practice.
• A higher RCV of 17%-21% is recommended for reliable detection of clinically meaningful GLS changes.
• The methodology for determining RCV is translatable to other imaging parameters.