Is pulmonary embolism still life threatening if it's diagnosed and treated?

It can be: A pulmonary embolism is potentially fatal. A 2002 study looked at people admitted to the hospital with PE and found that people who were unstable when they arrived at the hospital (CPR, on ventilator) had very high mortality rates (80%). People who were stable enough to have a CT scan had very low mortality rates (1-2%) Here is a link to the study https://www.ncbi.nlm.nih.gov/pubmed/12416281

PE: How you talking about fully treatedz for three to six months? Depends how big is the pulmonary embolism how many of them are there and where is the embolism isfound in your lungs.