7 lines (6 with data), 250 Bytes

m116a 0 128 0 15:15:00 30/01/1991
# Start time=15:15
# First beat=15:15:04.265
# <age-range>: 65-69, <sex>: Male, <medication>: None
# <RR-low-limit(sec)>: 0.57,  <RR-high-limit(sec)>: 1.07
# Note: recording with a timing signal, flutter-compensated