aortic dissection

Imagine the layered wall of a hose splitting from the inside, so that pumped fluid forces its way between the layers and carves out a false channel. Aortic dissection is exactly this: a tear in the inner lining of the aorta lets high-pressure blood drive between the wall's layers, peeling them apart along the vessel. It is one of the most dangerous emergencies in all of cardiovascular medicine.

The classic presentation is sudden, severe, tearing or ripping chest or back pain, sometimes described as moving as the tear extends. Depending on where the dissection travels, it can block branches supplying the heart, brain, kidneys, or limbs, leak into the sac around the heart causing tamponade, or rupture catastrophically. Risk factors include long-standing hypertension, connective-tissue disorders such as Marfan syndrome, and a bicuspid aortic valve.

Treatment depends on location. Dissections involving the first part of the aorta (the ascending aorta) are typically a surgical emergency, while those confined to the descending aorta are often managed first with aggressive blood-pressure and heart-rate control. Rapid diagnosis, usually by CT angiography, is critical because the risk of death climbs with every passing hour in the early phase.