Below is an instruction from Human. Write a response.
    ### Instruction:
    What are the symptoms of Patent Ductus Arteriosus ?
    ### Response:
    A heart murmur may be the only sign that a baby has patent ductus arteriosus (PDA). 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.
                
Some infants may develop signs or symptoms of volume overload on the heart and excess blood flow in the lungs.
    