Studying Left Ventricular Reverse Remodeling by Aortic Debanding in Rodents

Area of Science:

• Cardiovascular Biology
• Surgical Models
• Cardiac Physiology

Background:

• Left ventricular (LV) reverse remodeling (RR) is crucial for heart function recovery after injury.
• Existing models often lack the variability seen in clinical RR.
• Understanding the mechanisms of RR is vital for developing new therapies.

Purpose of the Study:

• To describe a reproducible rodent model for studying LV reverse remodeling (RR).
• To establish a minimally invasive surgical aortic debanding procedure in mice.
• To assess cardiac function and structure changes during RR using echocardiography and hemodynamic evaluation.

Main Methods:

• Aortic banding in mice to induce LV remodeling, followed by minimally invasive surgical debanding.
• Serial echocardiography to monitor cardiac hypertrophy, dysfunction, and filling pressures (E/e', LVEDP).
• Terminal hemodynamic assessment and histological analysis of cardiac tissue.

Main Results:

• Surgical survival rates for aortic debanding were 70-80%.
• Two weeks post-debanding, significant regression of ventricular hypertrophy (~20%) and fibrosis (~26%) was observed.
• Recovery of diastolic dysfunction, indicated by normalized LV filling and end-diastolic pressures, was achieved.

Conclusions:

• Aortic debanding in rodents provides a valuable experimental model for studying LV RR.
• The model mimics the variability of clinical RR, such as after aortic valve replacement.
• This model facilitates investigation into the mechanisms underlying cardiac hypertrophy regression and diastolic dysfunction recovery.