SarcOptiM for ImageJ: high-frequency online sarcomere length computing on stimulated cardiomyocytes

Area of Science:

• Cardiovascular Biology
• Biophysics
• Medical Imaging Analysis

Background:

• Accurate measurement of cardiomyocyte contraction is crucial for understanding cardiac physiology and diseases.
• Existing methods for quantifying cardiomyocyte contraction via sarcomere length are limited and not freely available.
• Contraction impairment is a key feature in various cardiac pathologies.

Purpose of the Study:

• To develop and validate a freely distributed software tool for precise measurement of cardiomyocyte sarcomere length.
• To provide a user-friendly solution for analyzing cardiomyocyte contraction dynamics.
• To overcome limitations of existing measurement techniques, including artifacts from motion.

Main Methods:

• Development of a plug-in named SarcOptiM for the ImageJ/Fiji image analysis platform.
• Utilizing fast Fourier transform (FFT) analysis on video frames for sarcomere length computation.
• Implementation of real-time and offline analysis modes, including a simulator and video generator.
• Testing with experimental recordings from rat ventricular cardiomyocytes and synthetic videos.

Main Results:

• SarcOptiM accurately computes sarcomere length from video frames, adaptable to various acquisition parameters.
• The tool functions in real-time or offline, mitigating motion-related artifacts.
• It supports high-speed analysis, with the algorithm capable of online sarcomere shortening computation at frame rates exceeding 10 kHz.
• The software is compatible with Windows, Mac, and Linux operating systems.

Conclusions:

• SarcOptiM is a validated, free, and user-friendly tool for studying cardiomyocyte contraction across all species, including humans.
• The plug-in enhances the study of cardiac physiology and diseases involving contraction abnormalities.
• Its open-source nature and broad compatibility facilitate wider adoption in scientific research.