Conductance Catheter Mice

The method pairs two synchronized signals rather than relying on pressure or volume alone. Electrodes estimate ventricular blood conductance by introducing a small electrical current, while the pressure sensor records intraventricular pressure. Combining these time-matched measurements produces pressure-volume loops, allowing cardiac performance to be examined as an integrated mechanical process in living mice.

Blood conductance provides the electrical signal used to track changes in ventricular filling and emptying during the cardiac cycle. Because the electrodes introduce only a small current and detect the resulting conductance, the recording can follow volume-related changes in real time. This makes it possible to evaluate dynamic cardiac behavior rather than a single static measurement.

It supplies intraventricular pressure data that electrical conductance alone cannot provide. When pressure is aligned with the conductance-derived volume signal, the resulting loop captures how the ventricle develops and releases force during a beat. This combined view supports assessment of systolic performance, diastolic performance, contractility, and relaxation in the same animal.

During an in vivo experiment, the miniaturized catheter provides simultaneous electrical conductance and intraventricular pressure signals. Researchers use these paired recordings to generate pressure-volume loops, then derive measures such as contractility, relaxation, stroke volume, and cardiac output. The workflow moves from signal acquisition to loop-based functional analysis, preserving real-time information about cardiac performance.

These measurements are useful when a study must connect molecular or structural changes to whole-heart function. The approach is applied in cardiovascular disease models, genetically modified mice, and drug-treatment studies. It can reveal whether an alteration affects systolic or diastolic performance, providing functional context that complements investigations focused on cardiac structure or underlying biology.

Researchers can compare pressure-volume-derived measures across experimental conditions to determine whether a drug treatment or genetic modification changes cardiac performance. Contractility, relaxation, stroke volume, and cardiac output provide distinct functional readouts rather than a single general impression of heart health. This comparison helps relate the intervention to measurable whole-heart outcomes in vivo.