7 lines (6 with data), 248 Bytes

m191a 0 128 0 12:05:00 08/02/1991
# Start time=12:05
# First beat=12:09:37.187
# <age-range>: 45-49, <sex>: Male, <medication>: None
# <RR-low-limit(sec)>: 0.453,  <RR-high-limit(sec)>: 0.945
# Note: reel-to-reel recording, not flutter-compensated