7 lines (6 with data), 251 Bytes

m147a 0 128 0 14:00:00 11/05/1991
# Start time=14:00
# First beat=14:07:51.023
# <age-range>: 70-74, <sex>: Male, <medication>: None
# <RR-low-limit(sec)>: 0.71,  <RR-high-limit(sec)>: 1.265
# Note: recording with a timing signal, flutter-compensated