Single-heartbeat electromechanical wave imaging with optimal strain estimation using temporally unequispaced...

Area of Science:

• Biomedical Ultrasound
• Cardiac Mechanics
• Medical Imaging Technology

Background:

• Electromechanical Wave Imaging (EWI) maps cardiac deformations from electrical activity.
• Conventional EWI faces frame rate limitations, hindering real-time and arrhythmia studies.
• Current methods combine data from multiple heartbeats, limiting temporal resolution and excluding non-periodic events.

Purpose of the Study:

• To introduce a novel acquisition sequence for high frame rate EWI.
• To enable real-time cardiac electromechanical wave imaging.
• To facilitate the study of both periodic and non-periodic cardiac electrical events.

Main Methods:

• Development and implementation of a temporally unequispaced acquisition sequence (TUAS).
• TUAS allows variable frame rates independent of imaging parameters.
• Application of TUAS for optimal frame rate determination in a paced canine heart and imaging during ventricular fibrillation.

Main Results:

• TUAS achieved high frame rates, enabling optimal EWI signal-to-noise ratio.
• The technique successfully imaged electromechanical waves in vivo within a single heartbeat.
• Ventricular fibrillation was imaged in real-time, demonstrating capability for non-periodic events.

Conclusions:

• TUAS significantly advances EWI by overcoming conventional frame rate limitations.
• This method allows for optimal, real-time EWI during physiological conditions and arrhythmias.
• Future applications include enhanced diagnosis and monitoring of cardiac electrical and mechanical function.