7 lines (6 with data), 248 Bytes

m113a 0 128 0 10:00:00 21/01/1991
# Start time=10:00
# First beat=10:00:00.531
# <age-range>: 45-49, <sex>: Male, <medication>: None
# <RR-low-limit(sec)>: 0.445,  <RR-high-limit(sec)>: 0.921
# Note: reel-to-reel recording, not flutter-compensated