List the structures the blood flows in the correct order.
(On bottom left)

Explanation:

At first, blood flows from the right atrium.

Then it goes into the right ventricle and through the tricuspid valve.

After that, when the ventricle is full, the tricuspid valve is there to shut to prevent blood flowing backwards into the atrium which can cause problems.

Then, blood leaves the heart through the lumonic valve and it goes into the pulmonary artery and then to the lungs.

i think he will be okay, id probably take the dog to the vet just incase