Thrombosis of upper extremity veins and superior vena cava (SVC) can occur in patients with indwelling central venous catheters. Contrary to earlier reports, pulmonary embolism (PE) can result from these thrombi, especially when they are attached to catheters (sleeve thrombi) in contrast to venous wall (mural thrombi). Removal of catheters may be required when sepsis occurs or to reduce risk of sepsis when lines have been left in for several days. We describe two patients with thrombi in SVC related to central venous catheters in whom transesophageal echocardiography (TEE) was performed during catheter removal to monitor for thrombus dislodgement. TEE may have a role in showing thrombus dislodgement and embolization during removal of venous catheters complicated by SVC thrombi. Direct visualization of thrombus dislodgement may aid in early diagnosis of PE because signs and symptoms of PE are often missed or mistaken for underlying cardiopulmonary disease. TEE may also play a role in implementing appropriate treatment in patients with PE who show right ventricular strain.