I have two responses for ya:
If it was a friend or family member or at least someone that I knew and respected on some level above what I would give generally to a fellow human being I would have taken them aside (as best as I could or possibly later in the evening when we could be more private) and explain simply what I had been through, what my condition was, and that I pay close attention to what I eat, how much I eat, and that I'm very well thankyouverymuch for your consideration...
If this was someone whom I did not know very well or (worse yet) cared little about, I would have hammered them right then and there and let everyone else see me put them in their place.
I'm brutal too:
"Two years ago I nearly DIED about half a dozen times over because my tricuspid valve disintegrated. I've never smoked in my life, I rarely drank and when I did it was never more than two bottles of beer in a NIGHT. I don't do drugs, I don't abuse my body. I eat well, I exercise, and I'm probably in the best shape I could be in for someone with the heart condition I have and I STILL nearly died and GUESS WHAT? I still watch what I put into my body, I watch it now more than I ever did in the past. I count the sodium I put into my body every day. I only allow myself about 1,000mg a day, the USDA recommendation is 2,000 and most people consume over 4,000mg. Can YOU do that? I limit how much fluid I drink too.
I'm having some fried shrimp (or whatever "sin" food you might be enjoying) here because they're good and I can treat myself once in a while and if you have a problem with that, you need to come to me AFTER you've been through the s*%t I've been through before you can tell me I'm wrong."
Or something along those lines.
Heaven help them if they smoke or have been enjoying an alcoholic beverage during the evening....
For the record, I LOVE shrimp, I can't get enough of it and I lucked out a while ago finding some VERY low sodium frozen shrimp that's almost always in a freezer bin at the local grocery store at two for one specials. I do a MEAN asian style shrimp stir-fry that's low sodium and low fat and very delicious thanks to a few home made ingredients like a low sodium soy sauce substitute that can be modified for teriaki (did I spell that right?) sauce.
Wonder if one can make a homemade, low sodium, cocktail sauce.....