Acute aortic dissection is a cardiovascular emergency with high mortality that necessitates prompt diagnosis and immediate treatment. Though asymmetric extremity pulses/blood pressures and mediastinal widening on chest roentgenogram are often clues to diagnosis, aortic regurgitation (AR) of variable degrees could be the only sign on initial assessment. Mostly resulting from dilated aortic ring with valvular insufficiency, the AR could be caused by different pathogenic mechanisms. Herein we report a case of Stanford type A aortic dissection presenting with acute pulmonary edema. Physical examination detected severe AR murmur and bedside echocardiogram confirmed prolapsed dissecting intima flap with interference of aortic valve closure as a specific mechanism.

A 36-year-old man presented with rapidly progressive dyspnea within hours. Physical examination disclosed a grade IV/VI diastolic murmur at aortic area and left parasternal border. Immediate bedside echocardiography revealed an onion-shaped aortic root with a dissecting intima flapping to-and-fro in between aortic root and left ventricular outflow tract, thus interfering with aortic valve closure and resulting in severe AR. Chest computed tomography confirmed a Stanford type A aortic dissection with the dilated aortic root well hidden in cardiac silhouette, making chest roentgenogram difficult for diagnosis. Emergency operation with Bentall procedure was performed smoothly and the patient was discharged uneventfully later.

Acute pulmonary edema resulting from severe AR is a specific presentation of aortic dissection. New-onset AR murmur, either caused by aortic ring dilatation or prolapsed intima flap interfering with aortic valve closure, may serve as a clue to timely correct diagnosis.