Below is an instruction from Human. Write a response.
    ### Instruction:
    What is (are) Parkes Weber syndrome ?
    ### Response:
    Parkes Weber syndrome (PWS) is a rare congenital condition causing an individual to have a large number of abnormal blood vessels. The main characteristics of PWS typically include a capillary malformation on the skin; hypertrophy (excessive growth) of the bone and soft tissue of the affected limb; and multiple arteriovenous fistulas (abnormal connections between arteries and veins) which can potentially lead to heart failure.
    