7 lines (6 with data), 248 Bytes

m289a 0 128 0 10:04:00 05/10/1988
# Start time=10:04
# First beat=10:21:45.671
# <age-range>: 60-64, <sex>: Male, <medication>: None
# <RR-low-limit(sec)>: 0.429,  <RR-high-limit(sec)>: 1.007
# Note: reel-to-reel recording, not flutter-compensated