Blood Clots in Your Legs Can Travel to Your Lungs or Heart. Here's How to Stop It

Blood clots are the third leading vascular cause of death — behind only heart attacks and strokes — and most people don't recognize the warning signs until it's an emergency. In Part 1 of this two-part series, cardiologist Dr. James Marcum explains how blood clots form, why blood clots when it stops moving, and the four things everyone needs to know about clotting (hemostasis).

Prompted by the news of an NFL quarterback's superficial blood clot and Kirk Herbstreit's pulmonary embolism, Dr. Marcum covers:
• What a blood clot is — platelets, clotting factors, fibrin, and the endothelium
• The main causes: immobility, injury, poor blood flow through an organ (atrial fibrillation, a weak heart), dehydration, smoking, estrogen, cancer, and inherited clotting disorders
• How a clot in the leg (DVT) can travel to the lungs (pulmonary embolism), brain (stroke), or heart (heart attack)
• Blood clot symptoms you should never ignore: leg swelling, shortness of breath, chest pain, and stroke-like symptoms
• Simple ways to lower your risk: get up and move every hour, compression stockings, stay hydrated, avoid cigarettes and estrogens, and lose extra weight