7 lines (6 with data), 248 Bytes

m122a 0 128 0 17:20:00 26/05/1991
# Start time=17:20
# First beat=17:20:00.757
# <age-range>: 65-69, <sex>: Male, <medication>: None
# <RR-low-limit(sec)>: 0.539,  <RR-high-limit(sec)>: 0.789
# Note: reel-to-reel recording, not flutter-compensated