Thanks for the informative article. My 67-year-old best friend just had a hard attack. She had low blood pressure, zero calcium score, low cholesterol, but the sudden heart attack was because of an extra electrical channel to her heart, or something like that. They are going to do an ablation. Also, because she's female, instead of having the usual heart attack symptoms she had extreme jaw pain, so her husband didn't believe she was having a heart attack.