Pulmonary Embolism Support Group
By far the most common form of pulmonary embolism is a thromboembolism, which occurs when a blood clot, generally a venous thrombus, becomes dislodged from its site of formation and embolizes to the arterial blood supply of one of the lungs. Symptoms may include difficulty breathing, pain during breathing, and more rarely circulatory instability and death.
They think it's a problem with my autonomic nervous system as a result of the PE's. I'm now on heart medication to control the high HR's.
Good luck with ur next echo.
http://patientblog.clotconnect.org/2011/06/29/chronic-lung-damage-after-pe-%e2%80%93-pulmonary-hypertension-cteph/
http://www.mayoclinic.com/health/pulmonary-hypertension/DS00430/DSECTION=tests-and-diagnosis
http://circ.ahajournals.org/content/123/16/1788.full
Scroll almost half way down for the section on Chronic Thromboembolic Pulmonary Hypertension