7 lines (6 with data), 252 Bytes

m155a 0 128 0 11:22:00 09/02/1991
# Start time=11:22
# First beat=11:34:44.226
# <age-range>: 55-59, <sex>: Male, <medication>: None
# <RR-low-limit(sec)>: 0.507,  <RR-high-limit(sec)>: 0.937
# Note: recording with a timing signal, flutter-compensated