Thrombectomy is a procedure used to remove blood clots in the lungs for patients with pulmonary embolism with with significant risk factors such as severe right heart strain, worsening instability, or a large clot burden.. Because it is invasive, it is generally recommended after thrombolysis has failed, but it may also be considered when clot-busting drugs are contraindicated—for example, in patients with a history of recent major surgery, active bleeding, prior hemorrhagic stroke, or very high bleeding risk. The decision depends on the patient’s situation and whether the hospital has the expertise and resources to safely perform the procedure.