It's kind of high.
If you were selling automobiles and every fifth one that rolled out the door ended up crashing and burning in a ditch within a day or two, you wouldn't shrug that off.
20 percent of people on the high dose is “high” but since most folks are on smaller doses, the actual number is a lot lower.
And if you already had a heart attack, if it means you will live a couple years longer, the risk is worth it.