ECG 2

Question 1

location V5-V6

Answer 1

anterolateral wall

Question 2

location 2, 3 Avf

Answer 2

inferior wall

Question 3

location of I, aVL

Answer 3

high lateral wall

Question 4

prolonged QT interval if the

Answer 4

QT interval is more than half the RR interval

Question 5

Causes of prolonged QT interval

Answer 5

1. Hypocalcemia
2. hypokalemia
3. hypomagnesemia
4. Class 1A or 3 anti-arrhythmic drugs
5. Hypothermia
6. Congenital Long QT syndrome

Question 6

hypercalcemia effect on QT interval

Answer 6

shortened

Question 7

hypocalcemia effect on QT interval

Answer 7

prolonged

Question 8

in hypokalemia

Answer 8

1. prolonged QT interval
2. T wave merges with the U wave
3. u waves frequent
4. T wave may be inverted

Question 9

in mild hyperkalemia

Answer 9

1. Tall T waves

2. Peaked & Symmetrical

Question 10

in moderate hyperkalemia

Answer 10

1. P &R waves flatten,
2. QRS & T broaden,
3. Big S waves develop

Question 11

in severe hyperkalemia

Answer 11

1. P & R waves gone,

2. S and T waves broaden in a “sine wave” pattern

Question 12

abnormalities in the QT interval and the T wave due to drugs, abnormal electrolytes or other causes predispose to ____

Answer 12

arrhythmias usually though alterations in repokarization

Question 13

There are ___ large boxes (heavy lines) between the R waves and ___ small boxes (thin lines) between the R waves.

Answer 13

6

30

Question 14

T wave is inverted, a sign of ____

Answer 14

ischemia

Question 15

ST elevation is a sign of ______.

Answer 15

transmural injury in an acute coronary syndrome, usually with a clot due to platelet aggregation obstructing a coronary artery.

Most commonly the injury is associated with an acute MI.
But, if the obstructed artery is quickly opened with angioplasty or a thrombolytic agent the ST elevation may partially or entirely reverse and much, or rarely all, injury avoided.

Question 16

very small Q waves

Answer 16

1. may not be pathological

2. But sizable Q wave is usually due to transmural necrosis.

Question 17

sizable means

Answer 17

at least one small box wide (≥0.04 seconds).

Question 18

When Q waves develop in leads which would normally be positive they give information on ___

Answer 18

localization of the infarct.

Question 19

Infarcts usually involve only the

Answer 19

left ventricle.

Question 20

Q waves in inferior leads (II,III, aVF) are due to_____.

Answer 20

inferior infarcts

Question 21

Q waves in leads V1-V4 are due to _____.

Answer 21

anterior wall infarcts

Question 22

Leads I, aVL and the anterolateral leads (V5,V6) are associated with ____

Answer 22

lateral wall infarcts.

Question 23

a transmural acute MI typically:

Answer 23

evolves over time

Question 24

acute MI early stage

Answer 24

1. rarely seen
2. lasts only a few minutes i
3. giant, upright “hyperacute” T waves.
4. T wave inverts (“ischemia”)
5. ST segments then rise (“current of injury”).

Question 25

In acute MI,____ are usually the last ECG findings to develop

Answer 25

Q waves

Question 26

in acute MI, sometimes, the ST elevation ___

Answer 26

precedes or occurs simultaneously with the T inversion. .

Question 27

When the QT interval is altered susceptibilities to __ increase.

Answer 27

arrhythmias

This is especially likely with QT prolongation.

Question 28

commonly QT prolongation is acquired due to ____

Answer 28

electrolyte abnormalities or drugs.

Question 29

Hypokalemia: common causes

Answer 29

1. overuse of diuretics
2. vomiting
3. diarrhea
4. Alkalosis
5. potassium losing nephropathies
6. excess aldosterone