7 lines (6 with data), 258 Bytes

m177b 0 128 0 15:30:00 04/03/1987
# Start time=15:30
# First beat=15:30:00.484
# <age-range>: 45-49, <sex>: Male, <medication>: Moricizine
# <RR-low-limit(sec)>: 0.484,  <RR-high-limit(sec)>: 0.687
# Note: recording with a timing signal, flutter-compensated