QRS

Question 1

How to measure QRS complex?

Answer 1

beginning of Q wave to end of S wave

Question 2

what is QRS complex?

Answer 2

the ventricular depolarisation

Question 3

whats the normal duration of a QRS complex?

Answer 3

<120ms (0.12s) 3 small boxes

Question 4

whats a normal Q wave?

Answer 4

<40 ms (0.04s) and <2mm depth 1 box across and 2 boxes down

Question 5

Whats an abormal QRS complex?

Answer 5

>120ms (0.12s) above 3 small boxes

Question 6

what could cause an abnormal QRS complex?

Answer 6

ventricular conduction defects such as bundle branch box (left and right ventricular hypertrophy)

Question 7

what could a low voltage (QRS <5mm) suggest?

Answer 7

hypothyroidism COAD - chronic obstructive airways disease myocarditis pericarditis and pericardial effusion

Question 8

how to measure left ventricular hypertrophy?

Answer 8

R wave in V5 >25mm

Question 9

how to measure right ventricular hypertrophy

Answer 9

Dominant R wave in V1 t wave inversion in V1-V3 or V4 Deep S wave in V6

Question 10

Answer 10

left ventricular hypertrophy

R wave in V5 >25mm

Question 11

Answer 11

right ventricular hypertrophy

V1 - dominant R wave

V1-V3 or V4 - T wave inversion

V6 - deep s wave

Question 12

whats a significant Q wave?

Answer 12

>40ms (0.04s) 1 small square

depth >2mm - 2 small squares

present couple days after MI

If present in lead III, consider PE