ECG

Question 1

Intraventricular Conduction Disturbance, Nonpecific

Answer 1

QRS >110 in adults (>90 in 8-16yo).

Specific criteria for RBBB and LBBB not met

Question 2

LVH

Answer 2

R in AVL + S in V3 >28mm (men) > 20mm (women)

S in V1 +r in V5 or 6 >35mm

R in aVL >11mm

Question 3

Right atrial abnormality

Answer 3

P > 2.5mm in II, III, aVF OR

P > 1.5mm in V1 or V2

Question 4

Left Atrial Abnormality

Answer 4

Terminal P in V1 >1mm deep and >0.04s in duration (one little box deep and one little box wide) OR

Notched P wave with duration >0.12 s in inferior leads

Question 5

RBBB

Answer 5

QRS >120ms
rsR’. rsr’, or rSR’ om V1 or V2
S wave duration > r wave in V6 OR >40ms in I and V6

Question 6

ST/T wave changes 2/2 LVH

Answer 6

ST-T segment displacement opposite in direction to the QRS

Question 7

Sinoatrial exit block

Answer 7

4 types:

1st. Not detectible on ECG
2nd. Grouped beating with a shortening P-P with constant P-R, and a P-P pause less than twice the usual P-P
3rd. Constant P-P with pause twice P-P interval
4th. Not detectible on ECG

Question 8

Prolonged QT interval

Answer 8

QTc >450ms in men, >460ms in women

QTC = QT/sq root (R-R in seconds)

Question 9

Log both 2:1 and Mobitz I or II if both seen on ECG

Answer 9

sjfd

Question 10

Log both Normal ECG and Sinus rhythm

Answer 10

asf

Question 11

Limb lead reversal

Answer 11

Negative p waves and QRS complexes in 1 and aVL
Upright P wave and normal QRS in aVR

Can mimic dextrocardia, but in limb lead reversal there is normal R wave progression

Question 12

Precordial lead reversal

Answer 12

Sudden decrease in r wave progression with return to normal in ensuing lead

Question 13

WPW Pattern

Answer 13

Short PR (NEEDED)
Slurred upslope of QRS with resulting complex >120ms
ST-T wave changes

Question 14

ST-T wav changes indicating ischemia

Answer 14

Greater than 1mmhorizontal or downsloping depression and/or TWI greater than 2mm

Question 15

Rate of AV junctional escape rhythm

Answer 15

40-60bpm

Usually narrow, but can be wide with native wide complex

Question 16

Rate of ventricular escape rhythm

Answer 16

20-40bpm

Question 17

RVH

Answer 17

Mean QRS axis greater than 100ms

R/S ratio in V1 ?1, R/S ratio in V5 or 6 <1, qR complex in v1 or r wave >7mm in V1

Question 18

Hypokalemia

Answer 18

Prominent U waves
Prolonged QT
ST segment depression and T wave flattening
Various degrees of AVB
VT or VF

Question 19

LAFB

Answer 19

LAD, with QRS <120ms

qR in 1 and rS in II and III