We present a case of a 91-year-old man presenting to the emergency department with a tearing back pain. The patient's history included an endovascular abdominal aortic repair because of an aneurysm. The transthoracic echocardiography (TTE) appeared normal; however, when transducer was positioned to the left of the spine for the posterior paraspinal window, a clear intimal flap was demonstrated in the descending aorta lumen. The multiphasic computed tomography of the aorta confirmed the diagnosis of Stanford Type-B aortic dissection. The patient underwent thoracic endovascular aortic repair, consisting of a descending aorta endoluminal graft placement and realizing a full metal jacket thoracic-abdominal aorta. At 3-month follow-up, the outcome appeared excellent. The case points out the usefulness of TTE via nonconventional windows in detecting Type-B aortic dissection.