The Chihuahua ( (listen); Spanish: chihuahueño) is the smallest breed of dog, and is named after the Mexican state of Chihuahua. However, as with any dog, owners should take care not to overfeed their Chihuahua, since obesity can result in increased rates of joint injuries, tracheal collapse, chronic bronchitis, and shortened lifespan. Chihuahuas are also prone to some heart-related disorders, such as heart murmurs and pulmonic stenosis, a condition in which the blood outflow from the heart's right ventricle is obstructed at the pulmonic valve.