Colloquia

Samenvatting

Cardiovascular diseases are a global health challenge requiring effective preventive strategies and minimally invasive interventions. LifeTec Group B.V. developed the PhysioHeartTM platform—a unique ex vivo isolated beating heart system using slaughterhouse hearts—to simulate cardiac conditions and study heart failures, heart pumps, and structural heart devices. Enhanced through the SIGNET project for MRI-guided therapies, the platform aims to enable real-time visualization of treatment effects.

This research focuses on the platform's physiological behaviour, particularly its electrophysiology and mechanical activation. Initially designed as a 2-chamber model simulating left-sided heart function, it lacks full cardiac dynamics. Therefore, measurements were performed in both 2-chamber and 4-chamber configurations to determine which setup is better suited for the platform. Ion imbalances were induced using boluses to assess their impact on electrophysiology and mechanical activation, crucial for early detection of heart failure indicators.

Findings from working mode experiments revealed variable activation patterns and conduction velocities (CV) between the 2-chamber and 4-chamber setups, with stable activation-recovery interval (ARI) modes but varied CV ranges. Grid pacing successfully localized activation sites, significantly enhancing visualization with bipolar electrogram (BEG) maps. Calcium bolus consistently increased ARI modes and mean CV, thereby enhancing cardiac output (CO) and stroke volume (SV). In contrast, magnesium bolus decreased ARI modes with mixed effects on CV and pressure-volume (PV) loops, while potassium bolus altered CV maps and had modest effects on ARI modes.

In conclusion, the PhysioHeartTM platform exhibits some differences in electrophysiology and mechanical activation between its 2-chamber and 4-chamber configurations, but not significant. Grid pacing effectively measures local activation patterns, particularly enhanced by BEG maps. The study of ion boluses demonstrates their substantial influence on both electrophysiology and mechanical activation, highlighting complex interactions. Future research aims to refine strategies for restoring optimal ion balance in cases of altered cardiac function.