7 lines (6 with data), 252 Bytes

m052a 0 128 0 11:30:00 29/11/1990
# Start time=11:30
# First beat=11:35:38.640
# <age-range>: 50-54, <sex>: Male, <medication>: None
# <RR-low-limit(sec)>: 0.492,  <RR-high-limit(sec)>: 0.976
# Note: recording with a timing signal, flutter-compensated