An In-Vitro simulator for investigating flow disturbances in the left ventricle during controlled external impact

Area of Science:

• Biomedical Engineering
• Cardiovascular Research
• Trauma Biomechanics

Background:

• Blunt trauma from motor vehicle crashes frequently causes severe injuries, with cardiac trauma being a significant cause of mortality.
• Previous research has focused on cardiac consequences post-impact, lacking detailed analysis of intraventricular flow dynamics during the impact event itself.

Purpose of the Study:

• To assess the feasibility of a custom-built left-heart simulator for recreating acute, time-controlled impacts on the left ventricle.
• To analyze the resulting intraventricular flow disturbances and pressure variations during simulated cardiac impacts.

Main Methods:

• A left-heart simulator was constructed using silicone models of the left atrium, ventricle, and aorta with bioprosthetic valves.
• A piston-cylinder system controlled ventricular function, while a secondary linear motor-actuated impactor simulated acute trauma at five different cardiac cycle timings.
• Pressure sensors and flow measurements in the ventricle and aorta captured dynamic changes before, during, and after impact.

Main Results:

• Impacts caused significant alterations in ventricular pressure, including a 52% increase during systolic impacts and a 422% decrease during diastolic impacts.
• Flow velocity fields demonstrated atypical outflow patterns toward the mitral valve during impact.
• The simulator successfully recreated time-controlled impacts and captured associated hemodynamic changes.

Conclusions:

• This study provides novel insights into intraventricular flow dynamics under acute blunt cardiac trauma.
• The findings contribute to a better understanding of cardiac injury mechanisms resulting from sudden impacts.
• The developed left-heart simulator is a feasible tool for investigating trauma-induced cardiovascular events.