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Deep Vein Thrombosis (DVT):

Blood clot located in a deep vein in a leg.

Pulmonary Embolism (PE):

Blood clot that has traveled from a deep vein to a lung.

DVT and PE are also known as VTE (Venous Thromboembolism)

900k cases

in the U.S. annually¹

100k deaths

in the U.S. annually¹

3rd leading

Cardiovascular cause of death behind heart attack and stroke²

  1. https://www.cdc.gov/ncbddd/dvt/infographic-impact.html
  2. Turetz M, et. Al. Epidemiology, Pathophysiology, and Natural History of Pulmonary Embolism. Semin Intervent Radiol. 2018. doi:10.1055/s-0038-1642036

Clinical Problem – leaving chronic wall adherent / impacted clots behind

Pulmonary Embolism (PE)

~30% of cases, clot is left behind

In 30% of cases, there are impacted, chronic clots causing blockages in the lungs, and these patients can be discharged with these obstructions still present.

Post treatment impacted clot remains:

  • Patient can experience elevated pulmonary artery pressures
  • Patients can experience pulmonary infarction

Deep Vein Thrombosis (DVT)

~70% of cases present with chronic wall adherent clots

In 70% of cases, there are chronic, wall adherent clots, causing blockages in the leg and these patients can be discharged with obstructions still present.

Post treatment impacted clot remains:

  • If clot breaks free, potential for Pulmonary Embolism
  • Patients can experience Post-Thrombotic Syndrome (PTS)
  • Impaired blood flow and damaged veins that leads to leg swelling, pain and skin ulcers

Terms Used To Define Types Of Clots

Acute (Soft) Clot

An acute clot, also known as a soft clot, refers to a blood clot that forms suddenly and is typically composed of fresh fibrin and platelets. These clots are often associated with recent injury, surgery, or trauma, and they can rapidly obstruct blood flow. Acute clots require immediate medical attention to prevent complications such as pulmonary embolism or stroke.

Sub-Acute (Medium) Clot

A sub-acute clot, also referred to as a medium clot, represents an intermediate stage in the clotting process between acute and chronic clots. These clots may have started to organize (where the fibrin protein starts to biochemically crosslink with other fibrin proteins) and incorporate elements like red blood cells, but they haven’t fully matured into chronic clots. Sub-acute clots may present with varying degrees of obstruction and symptoms depending on their size and location.

Chronic (Hard) Clot

Chronic clots, also known as hard clots, are well-established and organized (heavily crosslinked) blood clots that have been present for an extended time period. These clots have undergone significant restructuring, with layers of fibrin, collagen, and other components and are devoid of RBCs. Chronic clots can persist for weeks, months, or even years, posing a risk of complications such as post-thrombotic syndrome, chronic thromboembolic pulmonary hypertension or recurrent thrombosis if left untreated.

Thrombolytics (Clot-dissolving drug) Are Generally Ineffective In Treating Sub-Acute (Medium) And Chronic (Hard) Clots