Yes that is what i mean. The temporary wound cavity and all of the kinetic energy expelled can cause a heart attack even if the heart isnt hit. If the kinetic energy is high enough it can even rupture other organs as well without hitting them.
I thought that might be what you were getting at. There have been a number of discussions here and elsewhere over the years on "Ballistic Pressure Waves" or "Hydrostatic Shock" as it's sometimes referred to. While it is sometimes a factor in wounding at rifle velocities it is much less certain at handgun velocities. Meaning that even with a 125 gr. well made jhp bullets at 1400 fps there is no guarantee that any trauma will be induced outside of the direct path of the bullet and the permanent and temporary stretch cavities. There is absolutely no proof that a person hit with a 125 gr. bullet in the stomach from a .357 Magnum will suffer a heart attack, a stroke, or any damage to the heart at all unless the heart itself is directly struck.
There is ample proof of this but you can also reason it out.
How effective a bullet can be is dependent on a number of factors, bullet construction, weight, velocity, caliber and most of all shot placement. How the shooter handles the gun and if they can shoot it accurately is a large factor in the "shot placement" factor. Some shooters prefer a certain weight bullet because in their experience they shoot it better and it performs as well.
In the links I put up earlier you see that there are a number of loads and calibers that impact the gelatin as dramatically, and some more so, than the 125 gr. .357 Mag loads that they show.
How any particular bullet reacts when it hits bone does not solely depend on it's weight. It is not true that a 125 will bounce off bone while a 158 will break bone. It depends on the bullet type and construction, the velocity when it strikes, the energy when it strikes, what bones it hits and what angle it hits them at, etc. Either weight will punch through a bone if conditions are right.