lodged?
I almost jumped on that but I suppose it could be seen as lodged as long as you make the distinction with "a bullet lodged whereever". The bird shot entered his heart via the bloodstream and irritated the heart muscle. I'm not sure whether it was lodged or not.
As to the level of the events, this stands out as different only because it involves the dreaded firearm. Fords golf ball could have killed the man it hit as surely as the birdshot. If he had been as old as the Chaney victim it might have done so.
If the guy dies the incident will escalate in importance but alas, he is expected to live. I have no doubt that if the guy dies of heart trouble 10 years from now Chaney will be accused of shortening his life