7 lines (6 with data), 252 Bytes

m239a 0 128 0 10:53:00 30/03/1990
# Start time=10:53
# First beat=10:53:30.960
# <age-range>: 60-64, <sex>: Male, <medication>: None
# <RR-low-limit(sec)>: 0.531,  <RR-high-limit(sec)>: 1.132
# Note: recording with a timing signal, flutter-compensated