Global longitudinal strain: a useful everyday measurement?

Area of Science:

• Cardiology
• Oncology
• Medical Imaging

Background:

• Herceptin (Trastuzumab) is crucial for HER2+ breast cancer but carries cardiotoxic risks.
• Echocardiography monitoring, particularly left ventricular ejection fraction (LVEF), is vital, as a 10% LVEF drop can halt treatment.
• Conventional 2D biplane method of discs (2DEF) for LV function assessment has accuracy and reproducibility limitations.

Purpose of the Study:

• To compare the reproducibility of Global Longitudinal Strain (GLS) against 2D biplane method of discs (2DEF) in routine clinical settings.
• To evaluate GLS as an early indicator of cardiotoxicity during Herceptin treatment.
• To determine if GLS can prevent treatment interruption by enabling pre-clinical intervention.

Main Methods:

• Fifty echocardiograms from female patients on Herceptin were analyzed for both 2DEF and GLS.
• Measurements were repeated by the same operator (intra-operator variation) and a second operator (inter-operator variation) after a minimum 14-day interval.
• Reproducibility was assessed using direct comparison, intra-class correlation (ICC), coefficient of variation (CV), and Bland-Altman plots.

Main Results:

• Global Longitudinal Strain (GLS) demonstrated superior reproducibility compared to the 2D biplane method of discs (2DEF).
• These findings were consistent across intra-operator and inter-operator assessments.
• GLS was shown to detect myocardial damage earlier than 2DEF during Herceptin treatment.

Conclusions:

• Global Longitudinal Strain (GLS) is a more reproducible and practical tool for routine echocardiographic monitoring of Herceptin-induced cardiotoxicity.
• Enhanced reproducibility of GLS minimizes errors in clinical decision-making related to treatment management.
• Early detection of cardiotoxicity with GLS allows for timely intervention, potentially preventing Herceptin treatment suspension and improving patient outcomes.