ECGs

Question 1

what does the P wave represent?

Answer 1

atrial depolarisation

Question 2

how long should the P wave be?

Answer 2

0.08 - 0.1s

Question 3

what does the QRS complex represent?

Answer 3

ventricular depolarisationn

Question 4

how long should the QRS complex be?

Answer 4

<0.10s

Question 5

what does the T wave represent?

Answer 5

ventricular repolarisation

Question 6

what does the PR interval represent?

Answer 6

AV node delay

Question 7

how long should the PR interval be?

Answer 7

0.12 - 0.20s

Question 8

what does the ST segment represent?

Answer 8

ventricular systole

Question 9

what does the TP interval represent?

Answer 9

ventricular diastole

Question 10

how do you calculate heart rate from an ECG if the rate is regular?

Answer 10

300/number of large squares between the R-R interval

Question 11

how do you calculate heart rate from an ECG if the rate is irregular?

Answer 11

count the number of QRS complexes in 30 large squares and multiply by 10

Question 12

where is atrial repolarisation seen on an ECG?

Answer 12

it isnt

masked by the QRS complex

Question 13

what is the heart rate like in complete heart block?

Answer 13

regular

Question 14

describe first degree heart block

Answer 14

PR wave is longer than normal (>0.2)

Question 15

describe 2nd degree mobitz I heart block

Answer 15

progressive lengthening of the PR interval until a QRS is dropped

Question 16

describe 2nd degree mobitz II heart block

Answer 16

some P waves are not followed by QRS - no pattern

Question 17

describe complete heart block

Answer 17

no relationship between P and QRS