A 52-year-old woman was admitted to our emergency department with a suspected diagnosis of a thoracic disc prolapse. She presented with acute thoracic and vertebral pain of sudden onset that increased on movement and change of body position. An emergency echocardiography that was performed at the bedside showed aortic insufficiency, dilation of the aortic root, and membrane dissection in the ascending aorta. A thoracic contrast-enhanced CT angiogram verified acute aortic dissection Stanford type A, which resulted in immediate referral to the department of cardiothoracic surgery for an emergency replacement of the ascending aorta. In the emergency department, emergency bedside echocardiography facilitates the rapid evaluation of potential differential diagnoses in patients presenting with acute thoracic pain.