High pressure vessels carrying blood tend to be TOUGH.
In order to incapacitate a target you have to get a CNS shot or allow enough blood to leave the body to render an unconscious state.
Stretching an artery, or heart (which is tough muscle), will not release blood, nor is it a CNS shot.
This being said, there ARE tiny little veins and arteries branching off the main arteries leaving the heart, which loop back and supply blood to the heart muscle, proper. Severing THOSE (which are not nearly as tough or resilient as the "parent" artery) WOULD effectively stop the heart from functioning after a period of time, as it would no longer supply oxygen to the heart muscle proper.
But we're talking about vessels that are smaller in diameter than a toothpick and heavily "shielded" by the structure around it.
So no, you are not very likely at ALL to incapacitate someone due to hydrostatic shock or temporary stretch cavity.
This being said, a close shot to a CNS point (base of the skull) will render a person unconscious or paralyze them for quite a long time. Look up the miami shootout - a federal agent took a 223 round through the neck, missed the spine but the passing of the bullet "shocked" the spinal cord sufficiently to paralyze him for a great deal of time.
So ... plausible.
But not very likely.