7 lines (6 with data), 253 Bytes

e251a 0 128 0 9:30:00 17/12/1988
# Start time=09:30
# First beat=09:37:54.945
# <age-range>: 55-59, <sex>: Female, <medication>: None
# <RR-low-limit(sec)>: 0.453,  <RR-high-limit(sec)>: 0.976
# Note: recording with a timing signal, flutter-compensated