Pulmonary vein compression by tumor: an unusual Doppler flow pattern.

Pulmonary venous compression caused by a large lung mass was diagnosed in a 50-year-old female with metastatic renal cell carcinoma. The pulmonary venous flow pattern on Doppler revealed high flow velocity as well as the unusual finding of continued antegrade flow throughout the cardiac cycle (without reversal during atrial contraction). Extracardiac tumors can compress pulmonary veins, mimicking pulmonary vein stenosis. This may cause dyspnea due to elevated pulmonary venous pressures. This report describes an unusual pulmonary vein blood flow pattern in a patient with lung metastases.