7 lines (6 with data), 248 Bytes

m158a 0 128 0 10:45:00 13/01/1991
# Start time=10:45
# First beat=10:45:00.007
# <age-range>: 75-79, <sex>: Male, <medication>: None
# <RR-low-limit(sec)>: 0.601,  <RR-high-limit(sec)>: 1.023
# Note: reel-to-reel recording, not flutter-compensated