*Disclaimer: All subjects discussed are from the perspective of my own experience as a healthcare professional, and now as a patient. These are my individual experiences and opinions and not intended as medical advice.
So what is pulmonary embolism (PE)?
A PE occurs when a blood clot or embolism breaks off from somewhere within the veins, travels through one side of the heart, and lodges in the blood vessels of the lungs. These clots can be small and block off a small area of the blood supply, or large and/or numerous, shutting down much of the blood flow. This is a problem as we humans need oxygen to reach every tissue in our bodies in order to survive!
PE is usually as a result of a deep venous thrombosis (DVT) forming somewhere in the veins, usually the legs, but possibly the arms, or somewhere within the abdomen or pelvis. As the flow in the veins is in general from the outermost tips back towards the heart, then a clot breaking off will travel through the right chambers of the heart and into the network of vessels in the lungs where they lodge. The combined disease encompassing PE and DVT is called venous thromboembolism (VTE)
What causes VTE
There are known risk factors for VTE including surgery, trauma, immobilisation, cancer, pregnancy, long-haul flights as well as a genetic predisposition to clotting. The hormone oestrogen can also play a part in some embolic events and hormonal contraceptives or hormone replacement therapy (HRT) can be implicated if no other cause can be found - of note: pregnancy has a far higher risk for VTE than either hormonal contraceptives or HRT.
Current treatment
The current best practice is immediate anticoagulation (blood thinners) in order to prevent further clotting, to maximise flow around the clot and to allow the body to reabsorb the clot over a period of months and years. There are more invasive treatments available to directly dissolve and remove the clot using medication delivered over a catheter, however, this is not generally the first line of treatment and is still largely experimental.
Treatment myths
Unfortunately, during my admission, I was informed by junior doctors on several occasions that the treatment would dissolve my PE. At this point, I was receiving low molecular weight heparin. I am now on a direct oral anticoagulant (DOAC.) While both are effective at preventing more clots, they do not dissolve any but the smallest clots, and this is not a claim made by the drug companies (and believe me they would if they could!)
Clot, whether it is in the legs or the lungs is reabsorbed over time (or not) by the body. Sometimes it resolves fully, other times the body creates channels through the clot preserving some or all function if not form, and yet other times the clot becomes hard and impervious, stable but visible decades later.
By the way, none of the above is a criticism of junior doctors. I don't think they came about their incorrect information off their own bat. They are either not being informed or being given incorrect information.
My healthcare experience
I spent seventeen years in healthcare, working predominantly in imaging of the veins and arteries. Part of my job was imaging DVT, both for initial diagnosis, and then to monitor progress during treatment. This was where it frequently became obvious that patients were being told that their treatment was going to, or already had, dissolved their clot. How shocked they then were when there was still obvious clot in their veins, as expected when they returned for a follow-up scan. So are doctors genuinely unaware of the efficacy of the treatments they are administering or do they think patients just don't want to know?
