Vital Facts on Blood Clots: Risk Factors, Symptoms That Can Affect Extremities

Several factors can lead to excessive blood clotting, which refers to limited or blocked blood flow. Blood clots can travel to the arteries in the brain, heart, kidneys, lungs and limbs. And that can result in a heart attack, stroke, damage to the body's organs or even death.

Recent media articles have featured celebrities, including former athletes, detailing serious conditions caused by blood clots. One of the top underlying risk factors is atherosclerosis, a disease caused by plaque building up inside the arteries. Over time, the plaque may rupture after becoming brittle or inflamed. Platelets then clump together to form clots at the site of the damage. Platelets are the cell fragments in our blood that form clots.

Ripal Gandhi, M.D., a vascular interventional radiologist at Baptist Health Miami Cardiac & Vascular Institute

“Blood clots can form in the setting of preexisting atherosclerosis, which causes narrowing of the arteries,” explains Ripal Gandhi, M.D., a vascular interventional radiologist at Baptist Health Miami Cardiac & Vascular Institute, who specializes in minimally invasive treatments. “Once the narrowing reaches a critical level, thrombus can form and result in symptoms. The second main reason why a patient may develop blood clot in the arteries is due to clot that forms in the heart, and subsequently dislodges and flows to the arteries in the extremities.”

Top Risk Factors for Blood Clots

Conditions that can trigger excessive blood clotting in the heart and brain: Atherosclerosis; vasculitis (a disorder that causes the body's blood vessels to become inflamed); diabetes; heart failure; atrial fibrillation (the most common type of arrhythmia, or irregular heartbeat); being overweight or obese; and metabolic syndrome (a group of risk factors that increases your chance of having heart disease and other health problems).

“Family history of blood clots certainly can be a risk factor for developing clots,” adds Dr. Gandhi. “However, the vast majority of people who develop arterial clots do not have a family history.” 

Conditions that can trigger excessive blood clotting in the limbs include atherosclerosis; Peripheral artery disease (PAD), which is also referred to as peripheral vascular disease (PVD). 

DVT is a blood clot that affects the deep veins of the legs. A blood clot in a deep vein can break off and travel through the bloodstream. If the clot travels to the lungs and blocks blood flow, the condition is called pulmonary embolism. PAD or PVD refer to a narrowing of the peripheral arteries that carry blood away from the heart to other parts of the body. The most common type affects the lower-extremities, in which blood flow is reduced to the legs and feet.

According to Dr. Gandhi, the top symptoms affecting the arteries of the lower extremities include the following:

1. Claudication - pain in the calf, thigh, buttocks, or hip which worsens with ambulation. The symptoms improve when the patient stops walking.
2. Rest pain - typically in the foot which occurs at rest. 
3. Non-healing wound or ulcer in the foot. 

Blood clots that occur in the veins of the legs usually present differently than arterial disease. Patients often have lower extremity pain, swelling, red and/or warm skin. If the clot dislodges and travels to the lungs, it may present with shortness of breath, chest pain, dizziness, or even loss of consciousness.

If you have any such symptoms or underlying health conditions, see your physician about imaging tests that can confirm blood clots. “The most common diagnostic tests for arterial disease include an arterial noninvasive vascular examination, which includes an arterial ultrasound study,” said Dr.  Gandhi. “Further imaging, including an CT angiogram or an MR angiogram, may be needed for further evaluation.”

For DVT and pulmonary embolism, the most common tests include a venous ultrasound and CT pulmonary angiogram, respectively.

Here are more insights on blood clots from Dr. Gandhi:

Are medications, such as blood thinners, safe to take for managing PVD and clots? 

Dr. Gandhi: “Only your physician can determine if blood thinners are indicated, are safe, and should be taken for managing patients with PVD and clots. Most patients who develop clots in the setting of preexisting atherosclerosis do not require full dose blood thinners. An antiplatelet medication, such as a baby aspirin and low dose blood thinner, may be prescribed. Patients who have a clot in the heart, which breaks off and goes to the leg, may require full dose blood thinners.”

Are healthy lifestyle changes, such as exercise, weight management and healthy eating, helpful in managing PVD and preventing clots? 

Dr. Gandhi: “First line treatment for patients who present with claudication is optimization of medical therapy, exercise (often supervised exercise program), weight management and healthy diet.  This can improve symptoms and increase walking distance. More severe disease, such as patients with rest pain and non-healing wounds, typically require an invasive intervention.”

What are the top complications and potential long-term effects of PVD and clots (including amputations)?