Canker sores — or aphthous ulcers — are small, shallow ulcers that occur in the lining of your mouth. A canker sore starts as a white or yellowish mouth sore with a red border. They’re usually very small (less than 1 millimeter) but may grow to 1/2 inch to 1 inch in diameter. You can get canker sores on your tongue, gums, …

Your aorta is the largest artery in your body. It carries blood and oxygen from your heart to other parts of your body. It’s shaped like a curved candy cane. Your ascending aorta leads up from your heart. Your descending aorta travels back down into your abdomen (belly).

Coarctation of the aorta is a congenital (present at birth) heart defect. It’s also called aortic coarctation (pronounced “ay-or-tuhk” “koh-ark-TEY-shun”). This defect affects your baby’s aorta, which is the largest artery in their body. It carries oxygen-rich blood from your baby’s heart to the rest of their body. If your baby has aortic coarctation, one part of their aorta is narrower …

An aortic dissection is a tear in your aorta. This is the main artery that carries oxygen-rich blood away from your heart to the rest of your body. It runs through your chest and abdomen and down to your legs. A rare condition, an aortic dissection begins abruptly when a tear happens in the inner layer of a weakened area of your aorta. Blood surges …

Aortic valve disease is a group of conditions that affect your aortic valve and prevent it from working as it should. Your aortic valve is the “door” that manages blood flow out of your heart to the rest of your body. This valve allows blood to travel from your heart’s main pumping chamber (left ventricle) into a large artery called your aorta. From there, your blood travels …

Aortic regurgitation, also called aortic regurgitation, refers to a leaky aortic valve. With this condition, the leaflets or cusps of your heart’s aortic valve don’t close as tightly as they should. As a result, some blood that should move out of your heart leaks backward each time your heart beats. Your aortic valve is the “door” that opens and closes to control …

Aortic valve stenosis (or aortic stenosis) describes an aortic valve in your heart that’s narrowed or blocked. This interferes with the normal blood flow out of your heart. Because this condition restricts blood flow, it also limits how much oxygen your body gets. This can cause chest pain, shortness of breath and fainting. Aortic stenosis can cause heart damage, major health problems and even death. …

A thoracic aortic aneurysm is a bulge that develops in the part of your aorta that extends through your chest (thorax). You might hear it described as an expansion, ballooning or widening of your aorta. All of these words describe how an aneurysm disrupts the aorta’s normal, tube-like shape. A widened portion of your aorta qualifies as an aneurysm if it’s at least 50% …

Pseudomembranous colitis (PMC) is a severe form of colitis. In this condition, something attacks and injures your colon lining (mucosa). It might be bacteria, toxins or another illness. Your colon mucosa develops thickened, scab-like plaques over the wounds. Your healthcare provider might call these “pseudomembranes.” What are pseudomembranes? Pseudomembranes develop on mucous membranes, like your colon lining, when cells die. Your …

An aneurysm is a weak or expanded part of an artery, like a bulge in a balloon. Your arteries are large blood vessels that carry oxygenated blood from your heart to other parts of your body. If an area in an artery wall weakens, the force of blood pumping through can result in a bulge or aneurysm. Aneurysms usually aren’t painful. You …