What Causes a Venous Embolism?
Most cases of pulmonary embolism, about 90 percent, are caused by a venous thromboembolism originating from deep veins in the legs, known as deep vein thrombosis (DVT). Numerous risk factors contribute to the development of a venous embolism, similar to arterial embolisms. Various events that disrupt blood flow, such as post-surgical immobilization, pregnancy, or injury, significantly increase the likelihood of developing a venous embolism. Additionally, certain medications directly impact the blood and promote coagulation. Examples of such medications include estrogen-containing contraceptives and cancer treatments that enhance coagulation.
Understanding Paradoxical Embolism
Paradoxical embolism, also known as cross embolism, occurs when an embolus (a clot or any other foreign material) moves from the venous side to the arterial side or vice versa. Diagnosing paradoxical embolisms can be challenging for physicians. Many patients with this condition experience symptoms that mimic neurological issues or indicate an arterial embolism. Similar to venous embolisms, paradoxical embolisms typically originate in the legs. However, instead of travelling to the lungs, the embolus can travel to critical areas such as the brain or kidneys.