7 lines (6 with data), 250 Bytes

m103a 0 128 0 15:30:00 08/11/1990
# Start time=15:30
# First beat=15:43:24.414
# <age-range>: 60-64, <sex>: Female, <medication>: None
# <RR-low-limit(sec)>: 0.593,  <RR-high-limit(sec)>: 1.015
# Note: reel-to-reel recording, not flutter-compensated