[hwillis]

700k people per year in the US die from heart disease. There are ~18k surgeons (of all kinds) in the US. So even if 10% of them were cardiac surgeons, each surgeon has one person dying per day to worry about. They're busy.

Heart surgeries often happen on actively beating hearts. Tiny mistakes mean death. Infections mean death. Its a muscle which never gets rest, the majority of people in the US have clogged arteries and high blood pressure by the time they die.

Theres no artificial shortage. Heart surgery is really hard. Its the third hardest kind of surgery, right behind brains and rockets.