Interesting!

People do no realize how wide spread the GLP1 receptors are in the human body. GLPL1R is expressed on all muscles so heart muscle will be effected:

https://pmc.ncbi.nlm.nih.gov/articles/PMC5939638/

https://www.proteinatlas.org/ENSG00000112164-GLP1R/tissue

The way these drugs help loose weight is by increasing cellular activity by stimulating adenylyl cyclase and increased intracellular cAMP levels. It is not that hard and not a msytery to anyone who can think straight about human metabolism.