Measuring Cardiac Output in a Swine Model.

Area of Science:

• Cardiovascular Physiology
• Medical Research Methodologies
• Animal Models in Research

Background:

• Swine are valuable models for human cardiac research due to physiological similarities.
• Accurate measurement of cardiac parameters like stroke volume and cardiac output is crucial in swine studies.
• Established methods for cardiac assessment include contrast ventriculography, thermodilution, and pressure-volume loop (PV-loop) catheters.

Purpose of the Study:

• To compare the accuracy and correlation of three distinct methods for measuring cardiac output and stroke volume in swine.
• To evaluate the reliability of PV-loop catheters, contrast ventriculography, and thermodilution in a live swine model.
• To determine the most suitable method based on available resources and research needs.

Main Methods:

• Five Yorkshire swine underwent anesthesia and instrumentation for central venous and arterial access.
• Cardiac output was measured using thermodilution (cold saline bolus and temperature probe).
• Stroke volume and cardiac output were assessed via contrast ventriculography (left ventricular catheter and iodinated contrast) and PV-loop catheter (continuous pressure-volume data).

Main Results:

• All three methods demonstrated strong correlations with each other.
• PV-loop catheter and thermodilution showed the highest correlation (r=0.99, 3% error).
• PV-loop catheter and contrast ventriculography (r=0.95, 6% error); thermodilution and contrast ventriculography (r=0.95, 2% error) also showed good agreement.

Conclusions:

• PV-loop catheters, contrast ventriculography, and thermodilution are reliable and accurate for measuring cardiac parameters in swine.
• Each method offers advantages, allowing researchers to choose based on specific requirements and available resources.
• These validated techniques support robust cardiovascular research using swine models.