Doctors or nurses help please!!?

What would cause all these symptoms at time dark stools, vomiting tar like substances,small pupils, spacy, large lump by & death? This happened to my mom who did indeed die. The coroner claimed it was hypertensive cardiovascular disorder which is not possible when you know what those really are. You can't die from that but rather something caused from that ( stroke , heart attack ect). I need to know what happened however we can not do an autopsy due to the fact that she was cremated 2 weeks before receiving the coroners report. She was 46 yrs old.