Speckle tracking deformation imaging to detect regional fibrosis in hypertrophic cardiomyopathy: a comparison between...

Area of Science:

• Cardiology
• Medical Imaging
• Biomedical Engineering

Background:

• Hypertrophic cardiomyopathy (HCM) is characterized by myocardial hypertrophy and can lead to fibrosis.
• Cardiac magnetic resonance (CMR) with late gadolinium enhancement (LGE) is the gold standard for detecting fibrosis.
• Echocardiography-derived strain parameters, both 2D and 3D, are increasingly used to assess myocardial deformation.

Purpose of the Study:

• To directly compare 2D and 3D deformation parameters in hypertrophic hearts.
• To determine which deformation parameters best reflect underlying fibrosis in HCM, as defined by LGE-CMR.
• To investigate factors influencing the correlation between 2D and 3D strain measurements.

Main Methods:

• Inclusion of 40 HCM patients and 15 hypertensive (HTN) patients with myocardial hypertrophy.
• Acquisition of 2D and 3D speckle tracking echocardiography and LGE-CMR data.
• Analysis of correlations between 2D/3D deformation parameters and LGE, and regression analysis for influencing factors.

Main Results:

• 2D and 3D deformation parameters showed poor to moderate correlations and are not interchangeable.
• 3D longitudinal strain (LS) and circumferential strain (CS) were consistently higher than 2D values.
• Hypertrophy substrate (HCM vs. HTN) and magnitude influenced 2D-3D strain correlations.
• 2D-LS demonstrated the best area under the curve (AUC) for fibrosis detection, while 3D-LS showed higher specificity.

Conclusions:

• 2D and 3D deformation parameters are not interchangeable in hypertrophic hearts due to variability.
• Factors like hypertrophy substrate, magnitude, and tracking algorithm assumptions contribute to variability.
• 2D-peak segmental longitudinal strain remains the optimal parameter for tissue characterization and fibrosis detection in HCM.