Special Conditions on the EKG

Question 1

Early Repolarization

Answer 1

Occurs globally 
T wave closer to QRS = short QT interval
Can give appearance of ST segment elevation 
J wave – looks like a R-R’ 
Will not develop a diagnostic Q

Question 2

Hyperkalemia

Answer 2

Increased K+ in the blood, tall pointy T waves
Excess K+
- Low rate and MI will occur longer to establish resting membrane potential and depolarization
- Can be due to tissue/ organ damage

Question 3

Hypokalemia

Answer 3

Decreased K+ in the blood
Commonly mistook as 2:1 AV block
Flat t wave associated with U wave

Question 4

Hypercalcemia

Answer 4

Increased levels of Ca2+ in the blood
In extreme cases can lead to ventricular tachycardia
Looks similar to early repolarization
Due to broken bones, thyroid issues
Keeps the cell transiently positive
Decreased repolarization time = short QT interval, global looks like ST elevation

Question 5

Hypocalcemia

Answer 5

Decreased levels of Ca2+ in the blood
Due to excessive exercise in women, Vitamin D deficiency
Prolong QT = increased repolarization time
Decreased conduction velocity, can have wide QRS

Question 6

T wave inversion

Answer 6

Acute coronary syndrome – in corresponding leads
Hyperinflation – more likely to be global
- Hyperventilation

Question 7

Pericarditis

Answer 7

Infection of the pericardium 
Inflamed pericardial sac 
ST elevation in all leads 
No Q develops 
Common to have associated chest pain

Question 8

Low Voltage EKG

Answer 8

< 5mm QRS in lead of mean depolarization (commonly limb leads)
Seen in: COPD, obese individuals, also thyroid issues

Question 9

Non-specific changes

Answer 9

Small T

Clinically insignificant ST elevation or depression

Question 10

Acute Coronary Syndrome

Answer 10

Constellation of diseases
Can also occur due to extreme stress
Do not perform a stress test

Question 11

Corpulmonale

Answer 11

right sided heart failure due to:
- pulmonary hypertension
- heart constriction due to pericardial sac effusion (air within the cavity)
Alterans: altering of QRS height beat to beat
Usually every other beat wave forms change

Question 12

Pulmonary Emboli

Answer 12

SI , QIII inverted T in III
Can often have right axis deviation
Lead I sign for COPD – decreased P and decreased QRS < 3 mm in height or depth in the lead of mean depolarization

Question 13

Situs Inversus = all organs on the opposite side

Dextrocardia = heart is angled to the right/ on the opposite side of the body

Answer 13

LLII negative P waves
aVR will be positive
Right axis deviation or Extreme right axis deviation
Tiny or negative R in V5 and V6

Question 14

QT corrected

Answer 14

QT int/ sqt(R-R int) <0.44

Question 15

Intermittent Blocks

Answer 15

Mobitz
Right bundle branch block (rate related)
- Triggered at high rates
- More common on right since it is thinner
Hemiblocks
PAT (Paroxysmal atrial tachycardia
- Relates to Wolff Parkinson White
- Occurs due to a re-entrance circuit
- Conduction returns to the atria and then the ventricles

Question 16

Brugada Syndrome

Answer 16

Genetic defect of Na+ channels in the heart

ST elevation with a bundle branch pattern in V1 , V2 and often V3

Question 17

Wellen’s

Answer 17

Congenital left anterior descending stenosis
Seen in V1 – V4
Marked T wave inversion primarily in V2 and V3
Angina free with t wave inversion
If angina is present t wave inversion goes away