7 lines (6 with data), 250 Bytes

m055b 0 128 0 12:11:00 04/06/1991
# Start time=12:11
# First beat=12:34:55.070
# <age-range>: 65-69, <sex>: Male, <medication>: Moricizine
# <RR-low-limit(sec)>: 0.546,  <RR-high-limit(sec)>: 1
# Note: reel-to-reel recording, not flutter-compensated