Answer:
Because the heart is located in the left.
Step-by-step explanation:
The midsagittal section or the midsagittal plane is an imaginery plane that is accepted to cut the body into two equal parts from the middle as left and right. The reason why the midsagittal plane does not cut the heart in half is because the heart is located to the left of the thoracic cavity and does not intersect with the midsagittal plane line.
I hope this answer helps.