7 lines (6 with data), 258 Bytes

m232b 0 128 0 10:00:00 10/12/1989
# Start time=10:00
# First beat=10:08:21.234
# <age-range>: 70-74, <sex>: Male, <medication>: Moricizine
# <RR-low-limit(sec)>: 0.476,  <RR-high-limit(sec)>: 1.171
# Note: recording with a timing signal, flutter-compensated