7 lines (6 with data), 257 Bytes

m138b 0 128 0 10:35:00 18/02/1990
# Start time=10:35
# First beat=10:41:24.710
# <age-range>: 45-49, <sex>: Male, <medication>: Moricizine
# <RR-low-limit(sec)>: 0.46,  <RR-high-limit(sec)>: 0.898
# Note: recording with a timing signal, flutter-compensated