Volumetric imaging and computation to explore contractile function in zebrafish hearts.

Area of Science:

• Cardiovascular Biology
• Biomedical Imaging
• Computational Biology

Background:

• Cardiac contractile dysfunction is a major cause of global morbidity and mortality.
• Understanding cellular mechanisms of heart function is crucial for treating arrhythmia and heart injury.
• Zebrafish hearts offer a relevant model due to structural and electrical similarities to human hearts.

Purpose of the Study:

• To develop a novel framework for high-speed, high-resolution, 3D imaging of cardiac function at the cellular level.
• To investigate real-time volumetric data in live zebrafish hearts.
• To enable in-depth analysis of cardiac contractility and intercellular interactions.

Main Methods:

• Combined light-field microscopy and single-cell tracking for real-time volumetric data acquisition (200 vol/s).
• Utilized an expectation-maximization-smoothed deconvolution algorithm for enhanced resolution (lateral: 5.02 ± 0.54 μm, axial: 9.02 ± 1.11 μm).
• Applied deep learning for quantifying cell displacement, velocity, and volumetric tracking in a virtual reality environment.

Main Results:

• Achieved high-speed (200 vol/s) and high-resolution (5.02 μm lateral, 9.02 μm axial) 3D imaging of live zebrafish hearts.
• Successfully quantified myocardial motion and blood flow dynamics at single-cell resolution.
• Enabled real-time volumetric tracking of cardiac cycles from end-systole to end-diastole.

Conclusions:

• The developed framework provides unprecedented insights into cardiac contractility at the cellular level.
• This technology supports detailed investigation of intercellular interactions in cardiac health and disease.
• Offers a powerful tool for advancing the understanding of arrhythmia and heart injury mechanisms.