Aortic dissection is a tear inside the main artery of the body. Blood slips between the layers and can split the wall open, so symptoms strike fast and hard. Sudden chest pain is the hallmark. It feels like a ripping or tearing knife that shoots through to the back between the shoulder blades. Pain can migrate. As the tear moves downward, the ache can travel into the neck, jaw, belly, or lower back. Blood pressure is often high on one arm and low on the other. The difference can be 20 mmHg or more. Shortness of breath is common. You... Learn more