What are common cardiac or paracardiac masses?
The most common cardiac or paracardiac mass is thrombus. Patients with indwelling central venous catheters are at risk for developing right atrial thrombus, and patients with atrial fibrillation are at increased risk for developing left atrial thrombus. Deep venous thrombi of the extremities can migrate to the right atrium before causing a pulmonary embolism. Other causes of thrombus in the atria include hypercoagulable states and tumors that invade the inferior vena cava and propagate as tumor thrombus into the right atrium (e.g., renal cell carcinoma, adrenal carcinoma, and hepatocellular carcinoma). The most common primary cardiac neoplasm is a myxoma ( Figure 12-12, B and C ). Most myxomas are found in the left atrium and originate from the atrial septum. Myxomas may prolapse and cause valvular regurgitation.