Experimental right ventricular hypertrophy and failure in swine

Area of Science:

• Cardiovascular Physiology
• Animal Models

Background:

• Pulmonary arterial constriction can lead to right ventricular (RV) dysfunction.
• Understanding the hemodynamic and structural differences between RV failure and hypertrophy is crucial for clinical management.

Purpose of the Study:

• To compare hemodynamic and morphometric parameters in pigs with induced right ventricular failure and hypertrophy against normal controls.
• To identify specific variables that differentiate between RV failure, RV hypertrophy, and normal right ventricles.

Main Methods:

• Pulmonary arterial constriction was induced in pigs.
• Hemodynamic measurements (pressures, cardiac output) and ventricular weights were recorded.
• Data from 22 pigs with RV failure, 10 with RV hypertrophy, and 21 normal pigs were analyzed.

Main Results:

• Right ventricular peak systolic and end-diastolic pressures, cardiac output, and RV weight differentiated hypertrophied and failing hearts from normal hearts.
• Cardiac output was significantly lower in failing hearts compared to hypertrophied hearts.
• Left ventricular pressures and contractility indices (dP/dtmax, maximum [(dP/dt)/P]) did not distinguish between failing and hypertrophied RVs.

Conclusions:

• Hemodynamic and morphometric parameters, particularly cardiac output, can distinguish between right ventricular failure, hypertrophy, and normal states in a porcine model.
• Cardiac output is a key differentiator between RV failure and RV hypertrophy.
• Left ventricular function parameters were not significantly altered in this model to differentiate between RV failure and hypertrophy.