Structural and Functional Support by Left Atrial Appendage Transplant to the Left Ventricle after a Myocardial...

Area of Science:

• Cardiovascular Biology
• Regenerative Medicine
• Tissue Engineering

Background:

• The adult left atrial appendage (LAA) contains cardiac and myeloid progenitor cells.
• Myeloid progenitor cells in the LAA secrete pro-regenerative factors.
• Cardiac constructs can mitigate heart remodeling through physical support.

Purpose of the Study:

• To investigate the potential of LAA transplantation as a regenerative therapy for myocardial infarction (MI).
• To evaluate the combined effects of cell therapy and physical support from LAA patches in a mouse MI model.

Main Methods:

• Adult mouse LAAs were transplanted into recipient mice undergoing simultaneous MI.
• A decellularized LAA patch served as a control group.
• Cellular infiltration, phenotypes, and cardiac function were assessed post-transplantation.

Main Results:

• LAA patches integrated with the ventricular wall and showed cell migration into the MI area.
• Transplanted cells exhibited phenotypes of myeloid (F4/80+) and cardiac (troponin C+) cells.
• LAA patch treatment significantly improved cardiac performance and inhibited hypertrophic remodeling compared to controls.

Conclusions:

• LAA transplantation is a potential therapeutic strategy for myocardial infarction.
• This method offers a dual benefit of cell-based regeneration and physical patch support.
• LAA patches effectively reduce deleterious cardiac remodeling and improve heart function post-MI.