7 lines (6 with data), 254 Bytes

m279b 0 128 0 10:45:00 22/05/1988
# Start time=10:45
# First beat=11:02:13.234
# <age-range>: 60-64, <sex>: Male, <medication>: Moricizine
# <RR-low-limit(sec)>: 0.484,  <RR-high-limit(sec)>: 1.023
# Note: reel-to-reel recording, not flutter-compensated