Femtosecond laser-induced myocardial incision: Preclinical study towards new tools for precision cardiac surgery

Background

Advanced precise laser techniques for myocardial tissue removal still need to be further explored. Femtosecond laser technology, renowned for its high precision and relatively minor collateral damage in biological tissue processing, shows significant promise for myocardial excision.

Objective

This study examined the effects of laser power and scanning speed on myocardial cutting outcomes, as well as to evaluate the feasibility and clinical application potential of femtosecond lasers in myocardial incision.

Methods

In this in vitro study using porcine hearts, cubic volumes (1.0 cm³) were laser-cut at varying powers (1.0 W to 5.0 W) and scanning speeds (1.0 mm/s to 4.0 mm/s). A 1064 nm femtosecond fiber laser emitting 179 fs duration pulses at a repetition rate of 500 kHz was used. Digital optical microscopy measured incision width, depth and thermal injury area. Statistical methods including correlation analysis and linear regression were applied to analyze the relationships between variables, and pathological examinations assessed tissue structure and injury extent.

Results

Laser power and scanning speed significantly influenced the cutting width, depth, and extent of thermal damage, with laser power played a decisive role andshowed a clear positive correlation with cutting width, depth, and thermal injury. Scanning speed primarily affected cutting efficiency, indirectly influenced cutting outcomes. Pathological examination revealed that increased laser power led to changes in thermal damage to myocardial tissue, characterized by enhanced eosinophilia of myocardial cell cytoplasm.

Conclusions

Femtosecond laser technology facilitates precise myocardial incision through meticulous modulation of power and scanning speed, validated exceptional safety and feasibility while highlighting substantial clinical potential. Further research is required to investigate related mechanisms.