7 lines (6 with data), 258 Bytes

m284b 0 128 0 10:20:00 07/05/1989
# Start time=10:20
# First beat=10:27:31.531
# <age-range>: 60-64, <sex>: Male, <medication>: Moricizine
# <RR-low-limit(sec)>: 0.515,  <RR-high-limit(sec)>: 0.734
# Note: recording with a timing signal, flutter-compensated