Radial deformation by tissue Doppler imaging in multiple myocardial layers

Area of Science:

• Cardiology
• Medical Imaging
• Biomedical Engineering

Background:

• Assessing myocardial strain in distinct layers is crucial for diagnosing non-transmural heart conditions.
• Previous studies lacked demonstration of feasibility and optimal settings for multi-layer strain measurement in humans.

Purpose of the Study:

• To demonstrate the feasibility of measuring myocardial strain in multiple layers using 2D tissue Doppler imaging (TDI) in healthy humans.
• To define optimal machine settings for accurate multi-layer strain assessment.

Main Methods:

• 2D TDI of the left ventricular inferior wall was performed in 23 healthy subjects.
• Images were acquired using six different machine settings.
• Velocity, strain rate, and strain were measured in two and three myocardial layers.

Main Results:

• Significant differences in subendocardial versus subepicardial strain were observed in two-layer measurements (p<0.003).
• Maximal strain differences were noted with minimal radial and maximal lateral averaging.
• Three-layer measurements showed distinct strain values for subendocardial, midmyocardial, and subepicardial layers (p <0.05).

Conclusions:

• Feasible measurement of radial velocity, strain rate, and strain in up to three myocardial layers is demonstrated in healthy individuals.
• The diagnostic potential of this multi-layer strain assessment warrants further investigation in patient cohorts.