dP/dt_max: An underestimated prognostic factor in large animal infarction model

Area of Science:

• Cardiovascular Research
• Animal Models
• Biomedical Engineering

Background:

• Myocardial infarction (MI) research requires reliable large animal models.
• Accurate monitoring of cardiac function post-MI is crucial for understanding disease progression and testing therapeutics.

Purpose of the Study:

• To establish a reproducible minipig model for inducing myocardial infarction.
• To evaluate the combined use of cardiac magnetic resonance imaging (cMRI) and Pulse index Continuous Cardiac Output (PiCCO) for monitoring cardiac function changes after MI.

Main Methods:

• Induction of myocardial infarction in Pannon minipigs via a 90-min closed-chest balloon occlusion of the left anterior descending coronary artery.
• Cardiac function assessment using cMRI (measuring end-diastolic volume (EDV), end-systolic volume (ESV), and left ventricular ejection fraction (LVEF)) and invasive pressure monitoring (including aortic dP/dtmax) at baseline, 72 hours, and 720 hours post-MI.
• Utilized the PiCCO hemodynamic system for continuous cardiac output monitoring.

Main Results:

• Significant increases in EDV were observed at 72 and 720 hours post-MI compared to baseline, with further increase by Day 30.
• ESV significantly increased at 72 hours post-MI but did not change significantly by Day 30.
• LVEF and aortic dP/dtmax showed significant worsening at Day 3, with LVEF recovery by Day 30, while dP/dtmax remained significantly impaired.

Conclusions:

• The minipig model provides a reproducible platform for studying myocardial infarction.
• The complementary use of cMRI and PiCCO enhances the robustness and reliability of cardiac function monitoring in large animal models.
• This integrated approach aids in understanding the temporal dynamics of cardiac dysfunction following myocardial infarction.