"Genetic Heart Condition" is what families go with when they don't want to admit the truth.

Remember Zyzz? Young Bodybuilder who died from steroid use. His family maintains it was a "genetic heart condition" that killed him despite the fact his brother was arrested for dealing steroids.

All people have varying differences in genetics that lead to some people's hearts being inferior or superior to others. Put enough strain on the heart and you die. Could superior genetics have saved the person? Probably, so that's why "genetic heart condition" isn't entirely wrong but it's kind of like saying the reason I died from drowning is because I have a genetic lung condition in which I can't hold my breath for 10 minutes. Put a person in water long enough and it doesn't matter how good his lungs are at holding his breath, he'll die. The cause of death isn't genetic lung condition, it's drowning.

Fat people are dying by being fat not genetic heart conditions and Zyzz died from steroid use not a genetic heart condition.