Acute aortic dissection is an important differential diagnosis to exclude in the emergency presentation of patients with acute chest pain. Misdiagnosis can be fatal if treatment with antithrombotic agents (for presumed acute coronary syndrome) is administered. We present a series of two patients who presented to our center with acute DeBakey Type III (or Stanford Type B) aortic dissection where transthoracic echocardiography was useful in making the diagnosis, which was later confirmed by computed tomography contrast angiography of the aorta. Although transthoracic echocardiography has a lower sensitivity compared with other imaging techniques, it may still be helpful in the emergency setting, particularly in hemodynamically unstable patients, for whom there are sometimes unavoidable delays in getting contrast-enhanced computed tomography or more invasive investigations like transesophageal echocardiography to establish the diagnosis.