7 lines (6 with data), 260 Bytes

m176b 0 128 0 11:36:00 18/06/1991
# Start time=11:36
# First beat=11:48:58.406
# <age-range>: 60-64, <sex>: Female, <medication>: Moricizine
# <RR-low-limit(sec)>: 0.531,  <RR-high-limit(sec)>: 0.984
# Note: recording with a timing signal, flutter-compensated