Aortic dissection occurs when a tear in the intima — the innermost layer of the aorta — allows blood under systemic pressure to enter and propagate through the aortic wall, creating a false lumen. Dissections involving the ascending aorta (Type A) are surgical emergencies with mortality exceeding 1–2% per hour without surgery; Type B dissections (descending aorta only) are typically managed medically initially. The classic presentation is an abrupt, tearing or ripping chest pain radiating to the back — described by patients as the worst pain of their life. Misdiagnosis as heart attack or musculoskeletal pain is common and dangerous, as thrombolysis given for suspected MI can be catastrophic in dissection. CT angiography of the chest, abdomen, and pelvis is the diagnostic investigation of choice.
