As curiosity, I looked up the causes of pulmonary embolism, and came up with this: http://www.mayohealth.org/mayo/askphys/qa970604.htm Apparently pulmonary embolism is common in women who have these factors: smoking, hypertension, and obesity. http://www.healthlibrary.com/reading/pointers/feb97/risk.htm Going by the information provided on these pages, if Lisa McPherson did have a pulmonary embolism, it was due to her immobilization and bed rest. Lack of exercise is also mentioned, especially walking. The car accident, especially since by all accounts was a light fender bender, would not have caused this. Bed rest would have. Immobility is a possibility. All of those factors were present with Lisa McPherson if she did indeed die of a pulmonary embolism. It is noted also that in some cases, a massive pulmonary embolism can be removed with prompt medical treatment, according to the Mayo URL. Kaeli.