From the Guidelines
For cardiomyopathy monitoring, a transthoracic echocardiogram (TTE) is the recommended first-line imaging test. This non-invasive test should be performed every 1-2 years for stable patients or more frequently (every 3-6 months) if there are changes in symptoms or clinical status 1. The TTE provides comprehensive assessment of cardiac structure and function, including left ventricular ejection fraction, chamber dimensions, wall thickness, diastolic function, and valvular abnormalities.
Key Components of TTE for Cardiomyopathy Monitoring
- Left ventricular ejection fraction
- Chamber dimensions
- Wall thickness
- Diastolic function
- Valvular abnormalities For hypertrophic cardiomyopathy specifically, the TTE should include careful measurement of septal thickness, assessment for left ventricular outflow tract obstruction, and evaluation of systolic anterior motion of the mitral valve. In cases where TTE images are suboptimal or more detailed assessment is needed, a transesophageal echocardiogram (TEE) may be warranted.
Additional Imaging Modalities
For patients with suspected infiltrative cardiomyopathies like amyloidosis, strain imaging (speckle tracking) should be included as it can detect subtle myocardial dysfunction before ejection fraction declines 1. Stress echocardiography may be useful for evaluating dynamic outflow tract obstruction in hypertrophic cardiomyopathy or for assessing exercise capacity and functional reserve in dilated cardiomyopathy. Cardiac magnetic resonance (CMR) is an important tool to consider, especially for tissue characterization and risk stratification, but its use should be guided by specific clinical questions and the availability of resources 1.
From the Research
Echocardiogram Types for Cardiomyopathy Monitoring
- To monitor cardiomyopathy, various types of echocardiograms can be used, including transthoracic echocardiography (TTE) and speckle-tracking echocardiography (STE) 2, 3, 4.
- Myocardial strain imaging, which can be performed using TTE or STE, is a powerful method to diagnose cardiac disease and can be applied to any cardiac chamber 2.
- Left ventricular (LV) global longitudinal strain by speckle-tracking echocardiography is the most widely used clinical strain parameter and has been shown to be a sensitive method for diagnosing mild systolic dysfunction 2, 3, 4.
Specific Echocardiogram Parameters for Cardiomyopathy Monitoring
- LV global longitudinal strain (LV-GLS) has been shown to be a reliable parameter for differentiating myocarditis from healthy controls and has the greatest overall effect size compared to other measures such as LV ejection fraction (LVEF) and LV end-diastolic diameter (LVEDD) 3.
- LV-GLS has also been shown to be a predictor of adverse cardiovascular outcomes in patients with myocarditis 3.
- In patients with hypertrophic cardiomyopathy (HCM), LV-GLS has been shown to be lower than in controls, but endocardial circumferential strain (GCS) is maintained, suggesting a compensatory mechanism 5.
Clinical Applications of Echocardiogram Parameters
- Myocardial strain imaging has been shown to be useful in the surveillance and management of cancer therapeutics-related cardiac dysfunction (CTRCD) 6.
- Peak systolic global longitudinal strain (GLS) by speckle-tracking echocardiography has been shown to be an important prechemotherapy parameter that can independently predict subsequent adverse cardiac events 6.
- A 10%-15% early reduction in GLS by STE appears to be the most useful prognosticator for cardiotoxicity while on therapy 6.