It is now known that Eddie Guerrero died of heart disease. His wife Vicki said " that the blood vessels were very worn and narrow, and that just showed all the abuse from the scheduling of work and his past. And Eddie just worked out like crazy all the time. It made his heart grow bigger and work harder and the vessels were getting smaller, and that's what caused the heart failure. He went into a deep sleep.

Just found this, R.I.P Eddie.