ECG Flashcards
1
Q
what do the squares mean on an ECG?
A
small square = 40ms
large square = 200ms
2
Q
how do you calculate heart rate from an ECG?
A
1) 300 divided by number of large squares in one R-R interval
2) Number of QRS complexes x 6
3
Q
what is a normal PR interval?
A
120-200ms (3-5 small squares)
4
Q
what does a prolonged PR interval (>200ms/5 small squares) reflect?
A
AV block
