My dad (heart attack prone) has been given the huge 325mg aspirins (2 of them) during a "cardiac event", en route to a hospital; and you're right that it's RXed in low dose for people with heart issues. I'd guess this is another "got to publish
something" study, because there is probably a tenuous link between stomach perforation (ulcers) caused by long-term regular use of NSAIDS, and the resulting ulcer pain causing increased blood pressure.
I've had ulcers from ibuprofin "abuse" — apparently taking a few a day, a few times per week, is "abuse", so if I stub my toe they give me opiates
(Nevermind that the opiates have an acetaminophen base, which causes liver damage if used long-term. So I just buffer my stomach with Tums and pop the aspirins or Motrins if I get a headache.)