Hello Woonie,
Kirbiboh gave good information below....They'yre finding our more and more as the years wear on ofcourse, and have been drawn to conclude that perhaps a Connective Tissue Disorder or Kidney disease could be precursors to an aneurysm forming--but not enough is known yet. They do know that family history plays a big role, and that lots of people have them and die before they're ever discovered due to 'old age' , etc. Glad yours was found..
Peace, Janet