What is the treatment for blood clots? Can it go away without treatment?
Depending upon their location, blood clots may be aggressively treated or may need nothing more than symptomatic care.
Blood clots in superficial the veins (venous blood clots)
- Clots may develop in the superficial or deep veins of the leg.
- Treatment for a superficial blood clot is directed at managing pain and decreasing inflammation with medication (for example, acetaminophen [Tylenol and others] or ibuprofen [Advil, Motrin, etc.]).
- The risk of these clots lodging and obstructing (embolizing) in the vein is low because of the anatomy of the leg.
- Specialized veins (perforator veins) connect the superficial veins to the deep veins, and have valves that act like strainers to prevent clots from traveling to the lung.
Clots in the deep vein system of the arm or leg may need to have the blood "thinned" with anticoagulation medications.
The American College of Chest Physicians' 2016 guidelines recommend that patients who have deep vein thrombosis (DVT) or pulmonary embolus (PE) be treated with different anticoagulation medications depending upon their situation.
- Patients with DVT or PE who have no active cancer should be treated with NOACs (novel oral anticoagulant) medications. These are also known as DOACs (direct oral anticoagulant).
- Patients with DVT or PE who have active cancer should be treated with low molecular weight heparin (enoxaparin [Lovenox])
NOACs work by blocking factors in the clotting cascade. These include:
Direct thrombin inhibitor
- dabigatran (Pradaxa)
Enoxaparin (Lovenox) is a low molecular weight heparin that may be injected under the skin to "thin" the blood and anticoagulate the patient. In addition to its indication to treat DVT and PE in cancer patients, it is often used as a bridge treatment should a patient be treated with edoxaban, dabigatran, or warfarin, since these medications take time to reach a therapeutic level in the body. Enoxaparin is often the medication of choice in pregnant patient who develop blood clots like a deep vein thrombosis or pulmonary embolism.
Unfractionated heparin is used intravenously to anticoagulate a patient in the hospital, especially if the patient is unstable due to an underlying condition.
Warfarin (Coumadin, Jantoven)
Warfarin (Coumadin, Jantoven) is one type of anticoagulation medication that has been used for many years to treat blood clots. It blocks clotting factors II, VII, IX and X, those that depend upon Vitamin K, and historically was prescribed as soon as DVT (deep venous thrombosis) or blood clot is diagnosed. Because it takes a few days to effectively thin the blood, low molecular weight Heparin (enoxaparin) or regular heparin is used to immediately cause anticoagulation.
Pulmonary emboli are treated similarly to deep venous thrombosis, but depending on the severity of the symptoms, the amount of clot formation, and the underlying health of the patient, admission to the hospital for treatment and observation may be needed. Usually, unstable or potentially unstable patients are treated with intravenous unfractionated heparin.
Patients who are critically ill and display symptoms of heart strain or shock may be candidates for thrombolytic therapy using drugs known as tissue plasminogen activators (tPA). tPA may be injected into a peripheral vein in the arm to immediately thin the blood and act as a clot-busting drug or it can be dripped directly into the clot through a catheter that is placed by an interventional radiologist.
Arterial blood clot treatment
Arterial blood clots are often managed more aggressively. Surgery may be attempted to remove the clot, or medication may be administered directly into the clot to try to dissolve it. Alteplase (Activase, r-tPA) or tenecteplase (TNKase) are examples of tissue plasminogen activator (see above) medications that may be used in peripheral arteries to try to restore blood supply.
This same approach is used for heart attack. If possible, cardiac catheterization is performed to locate the blocked blood vessel and a balloon is used to open the occluded area, restore blood flow, and place a stent to keep it open. This is a time-sensitive procedure and if a hospital is not available to do the procedure emergently (within 60-90 minutes of the patient's symptoms) TPA or TNK may be used intravenously to try to dissolve the thrombus and minimize heart damage. Eventually, when stable, the patient will be transferred for potential heart catheterization to evaluate the heart anatomy and decide whether stents may be needed to keep an artery open or whether bypass surgery might be needed to restore blood supply to the heart.
Stroke is also treated with tPA if the patient is an appropriate candidate for this therapy. As well, there are now opportunities in some hospitals to have an interventional radiologist or neurologist thread a catheter into the blocked artery in the brain, try to find the clot causing the stroke, and remove it. This same strategy is used for heart attack and some patients with peripheral artery clots in an arm or leg.