ber of samples in record (integer)
       LengthTime              : Duration of record  (String WFDB Time)
       RecordName              : Record name (String)
       RecordIndex             : Record Index (Integer)
       Description             : Signal Description (String)
       SamplingFrequency       : Sampling Frequency w/ Units (String)
       File                    : File name (String)
       SignalIndex             : Signal Index (Integer)
       StartTime               : Start Time (String WFDB