Right, so just to iterate, pulling a heart out isn't really a good feat. You're much better off calculating the power needed to get to the heart in the first place. I'll show you why.
So, the aorta (the thickest artery) has a diameter of less than 3 cm (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1861012/ ) and has a wall thickness of 4 to 9 mm depending on your risk to get a disease from it: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5124617/
I'm technically calculating the maximum strength needed to perform the feat by going off the 3 cm limit for aorta diameter, bear in mind the aorta is the largest blood vessel. Let's determine the cross-sectional area of the aorta. First, we start with the aorta itself.
π*(0.03/2)²=7.068583471*10-4 m²
After that, we calculate the area of the hollow parts.
Low End: 0.03-0.004*2=0.022 meters (diameter)
π*(0.022/2)²=3.801327111*10-4 m²
High End: 0.03-0.009*2=0.012 meters (diameter)
π*(0.012/2)²=1.130973355*10-4 m²
Yeah, you can see how small all this is. Now, let's do the math to determine the cross-sectional area of the aorta wall:
Low End: 7.068583471-3.801327111=3.26725636*10-4 m²
High End: 7.068583471-1.130973355=5.937610115*10-4 m²
The ultimate tensile strength of human cardiac muscle, or myocardium, is only 3-15 kPa: https://onlinelibrary.wiley.com/doi/full/10.1002/adfm.201908612
Let's see how strong someone needs to be to pull it off.:
Low End: 3.26725636*10-4*3000=0.9801769079 newtons
High End: 5.937610115*10-4*15000=8.906415173 newtons
Only 0.98 to 8.91 newtons. Below Average Human lifting strength. Freaking Togame and Mr. Burns would have absolutely no issue pulling this feat off! It should be noted that the heart is usually pulled out in a quick jerklike motion. The distance from the heart to the skin at the sternum is 32.1 mm (3.21 cm) (https://pubmed.ncbi.nlm.nih.gov/18187292/ ) and the mean width of a heart is 8.21 cm according to a study on 550 Iranian human cadavers (https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5075360/ ). This should add up to a minimum distance to get the heart out of the body at 0.1142 meters. Let's see the results.
Low End: 0.9801769079*0.1142=0.11193620288 joules
High End: 8.906415173*0.1142=1.01711261276 joules
That's 0.11193620288 to 1.01711261276 joules. Below Average Human level, no contest!
This is why I said that you're much better off calculating the force needed to get to the heart in the first place. According to this article, a punch with a force of 3300 newtons has a 25% chance of breaking a single rib: https://www.nbcnews.com/health/health-news/study-how-many-punches-can-guy-take-flna1c9442336
This should make for an effective minimum requirement for pulling off the feat. Generally, the heart is assumed to be fist-sized, and anatomical diagrams of the heart show that the heart of a human is blocked by 3 or 4 ribs. Let's assume 3 ribs for the sake of this calculation as the diagram for the heart size showed a fist upright rather than from the knuckles. This would mean the width is more accurate than the height. This would provide an effective minimum force of 9900 newtons. The distance needed to get to the heart is 32.1 mm (3.21 cm) as stated before. Let's see how much work is required to punch through the chest and get to the heart.:
9900*0.0321=317.79 joules.
That's 317.79 joules, which is Street Level. I was also told that some characters can punch through the chest in doing this feat. In that case, the average depth gathered from men and women are 15.5 cm ((15.2+15.8)/2) and 14.85 cm ((14.5+15.2)/2) respectively.: https://www.researchgate.net/figure/Comparison-of-chest-depth-and-chest-width-among-males-and-females-adjusted-for-different_tbl1_8504154
I'll assume the same conditions for rib count here. Adding the heart's width (8.21 cm) to this figure since punching through the chest typically shows either the fist or a torn-out heart... Here's what I got.:
Men: 9900*0.2371=2347.29 joules
Women: 9900*0.2306=2282.94 joules
Punching through the chest is a lot higher, but still at Street Level. So yeah, there you have it.