7 lines (6 with data), 252 Bytes

m223a 0 128 0 10:37:00 22/07/1990
# Start time=10:37
# First beat=10:44:49.625
# <age-range>: 50-54, <sex>: Male, <medication>: None
# <RR-low-limit(sec)>: 0.484,  <RR-high-limit(sec)>: 1.148
# Note: recording with a timing signal, flutter-compensated