7 lines (6 with data), 254 Bytes

m270b 0 128 0 10:50:00 08/06/1989
# Start time=10:50
# First beat=11:12:31.390
# <age-range>: 60-64, <sex>: Male, <medication>: Moricizine
# <RR-low-limit(sec)>: 0.664,  <RR-high-limit(sec)>: 1.343
# Note: reel-to-reel recording, not flutter-compensated