7 lines (6 with data), 251 Bytes

m108a 0 128 0 8:00:00 15/04/1990
# Start time=08:00
# First beat=08:00:00.703
# <age-range>: 65-69, <sex>: Male, <medication>: None
# <RR-low-limit(sec)>: 0.507,  <RR-high-limit(sec)>: 1.031
# Note: recording with a timing signal, flutter-compensated