The closest I get to this vortex is to look at the type of pump.
There are two main ways to pump fluids, positive displacement - this is where the internal volume is squeezed and reduces such that the internal chambers are reduced in size - which evacuates the fluid through the outlets, this is especially easy to imagine in something like a piston engine or a heart. If there is no outlet or the outlet is blocked then the pressure continues to rise until something gives, either the pump cannot drive against a non-compressible fluid any more and stalls or something breaks
The other main type is the vane or fluid vortex type, here we have rotating vanes, such as in an aircraft engine, or perhaps in some types of air compressor, the internal space does not change in shape or size in any way, instead the vanes create a pressure on one side and a vacuum on the other, and the fluid - be it air or liquid will move from the higher pressure zone to the lower pressure zone, and if there is no outlet to release the pressure then it will build up to a point where back pressure is enough to prevent any further fluid passing through the vanes - blockage of the outlet is not likely to be harmful to the pump in mechanical terms but there may be serious heat build up.
There are different flavours of other pumps, such as peristaltic pumps which are similar to the way your intestines work, heat conversion pumps etc, but in general these are for relatively specialised purposes and not used to large volumes of fluid.
So what it appears to me is that your quack medic is doing is trying to conflate two engineering ideas, the vane pump which produces a vortex, and the positive displacement pump.
It is utterly clear that the heart is not a vane pump, it does not have vanes and has no rotating parts, additionally I also add that a vane pump does not need non-return valves, whereas positive displacement pumps absolutely must have them, in the human heart the leakages of non-return valves can be a significant medical problem that requires serious surgery.
Take this to your friend, the heart is a displacement pump, tell him to look the up the term displacement pump and add in human heart, tell him to look up the basic principles of pumps.
This quack I has no significant engineering knowledge, it is not my specialist area either but I have spent many a happy hour maintaining them - this is an ignorant person who seems to think that rest of us are not clear on very basic engineering terms and principles, this sort of shite would never have flown fifty years ago, and that’s because back then there were far more skilled hand-on people around, nowadays there is a general ignorance of such matters among a larger percentage of the population.