Thromboembolic

Thromboembolism describes the process by which a thrombus forms within a blood vessel and may detach, becoming an embolus that travels to distant sites and occludes vessels. The term thromboembolic is used for conditions and events related to clots and their consequences.

Pathophysiology centers on Virchow's triad: hypercoagulability, abnormal blood flow (stasis or turbulence), and endothelial injury. A dislodged thrombus fragments can lodge in arteries or veins, causing ischemia depending on its destination.

Venous thromboembolism (VTE) includes deep vein thrombosis and pulmonary embolism. Arterial emboli can lead to stroke or myocardial infarction. Combined, thromboembolic events are a major cause of preventable morbidity and mortality in many settings.

Risk factors include surgery or trauma, prolonged immobilization, cancer, pregnancy, estrogen-containing medications, obesity, age, smoking, and inherited or acquired thrombophilias such as Factor V Leiden, prothrombin gene mutation, or protein C/S and antithrombin deficiencies.

Diagnosis relies on clinical assessment and imaging: compression ultrasound for DVT, D-dimer testing, and CT pulmonary angiography or ventilation–perfusion scans for suspected PE. Laboratory tests evaluate coagulation and secondary causes.

Treatment centers on anticoagulation with heparin, followed by direct oral anticoagulants or warfarin, with duration guided by risk factors. In life-threatening cases, thrombolysis or catheter-directed thrombectomy may be used. Prevention of recurrence includes risk factor modification and, when appropriate, mechanical prophylaxis.