From the Guidelines
Severely abnormal left heart strain is typically defined as a left ventricular global longitudinal strain (GLS) value worse than -12%. This definition is based on the understanding that normal GLS values range from -18% to -22%, with less negative numbers indicating worse cardiac function 1. Values between -12% and -18% suggest mild to moderate abnormality, while values above -12% (such as -10% or -8%) represent severe abnormality.
Key Considerations
- The measurement of left ventricular global longitudinal strain (GLS) is obtained through echocardiography with speckle tracking, which detects subtle myocardial dysfunction before ejection fraction decreases 1.
- Severely abnormal strain patterns may manifest as regional wall motion abnormalities or global dysfunction and often precede clinical symptoms.
- They can indicate various cardiac conditions including coronary artery disease, cardiomyopathies, valvular heart disease, or cardiotoxicity from chemotherapy.
Clinical Implications
- Early detection of abnormal strain allows for prompt intervention with appropriate medications (such as beta-blockers, ACE inhibitors, or ARBs) and lifestyle modifications to prevent further cardiac remodeling and deterioration of heart function 1.
- It is essential to consider the clinical context when interpreting GLS values, as the same value may not reflect the same degree of abnormality in different contexts 1.
Important Factors
- The normal range publications for GLS values were largely derived from a western population, predominantly Caucasians from the UK 1.
- Different analysis approaches and imaging modalities may have a clinically relevant impact on results, and using the same cut-off values for different CMR techniques needs to be interpreted with caution 1.
From the Research
Left Heart Strain
- Left heart strain, also known as left ventricular (LV) strain, refers to the deformation of the myocardium in the left ventricle of the heart.
- It is an important marker of LV systolic function and can be measured using echocardiography, particularly global longitudinal strain (GLS) analysis 2.
Severely Abnormal Left Heart Strain
- Severely abnormal left heart strain is typically defined as a GLS value of -12% or worse, although this can vary depending on the specific clinical context and population being studied 2, 3.
- A GLS value of -12% or worse indicates significant impairment of LV systolic function and is associated with a higher risk of adverse cardiovascular events, such as heart failure and cardiac death 2.
- Other factors, such as the presence of ST-segment depression or atrial fibrillation, can also influence the interpretation of left heart strain and should be considered in the clinical assessment of patients with suspected cardiovascular disease 4.
Clinical Significance
- Left heart strain is an important prognostic marker in patients with heart failure, acute coronary syndromes, and other cardiovascular conditions 5, 2.
- It can provide valuable information on the severity of LV dysfunction and guide treatment decisions, such as the initiation of specific therapies or the need for closer monitoring 2, 3.
- The use of GLS analysis has been shown to improve diagnostic accuracy and prognostic value in patients with cardiovascular disease, particularly in those with preserved LV ejection fraction 2.