Severe acute heart failure - experimental model with very low mortality

Area of Science:

• Cardiovascular Research
• Animal Models
• Extracorporeal Circulation

Background:

• Advancements in extracorporeal circulation necessitate reliable models of acute heart failure.
• Existing models require improvement in control and reproducibility for experimental research.

Purpose of the Study:

• To develop and evaluate a reproducible model of severe, stable acute heart failure in pigs.
• To compare a hypoxic model with an ischemic model for inducing heart failure.

Main Methods:

• Two models were tested in pigs: hypoxic (n=5) and ischemic (n=9) induction of acute heart failure.
• Severe heart failure was defined by a ≥50% decrease in cardiac output, <60% mixed venous oxygen saturation, <25% ejection fraction, and ≥50% reduction in carotid artery flow.
• The ischemic model involved proximal left coronary artery closure and controlled hypoperfusion.

Main Results:

• The ischemic model successfully induced severe heart failure in 8 out of 9 animals without acute mortality.
• Significant reductions were observed in cardiac output (6.70 to 2.89 L/min), mixed venous saturation (83% to 58%), ejection fraction (50% to 19%), and carotid flow (337 to 136 mL/min) (P≤0.001).
• The hypoxic model resulted in heart failure in only one animal.

Conclusions:

• The proposed ischemic model provides a stable and reproducible method for inducing acute heart failure in pigs.
• This model is well-suited for experimental research supporting extracorporeal circulatory support systems due to its lack of acute mortality.