Below is an instruction from Human. Write a response.
    ### Instruction:
    How to diagnose Patent Ductus Arteriosus ?
    ### Response:
    In full-term infants, patent ductus arteriosus (PDA) usually is first suspected when the baby's doctor hears a heart murmur during a regular checkup.
                
A heart murmur is an extra or unusual sound heard during the heartbeat. Heart murmurs also have other causes besides PDA, and most murmurs are harmless.
    