Differentials

Question 1

New onset A.fib

Answer 1

Hyperthyroidism, heart valve disease, CAD, cardiomyopathy, COPD, asthma, excessive alcohol consumption, obstructive sleep apnea, cigarette or stimulant use, periods of extreme stress or fatigue can trigger episodes of AF, family history (idiopathic atrial fibrillation), PE, sepsis

Question 2

Wide QRS

Answer 2

1) Electrolytes (hypokalemia)
2) WPW
3) Hypothermia
4) Bundle Branch Block
5) Ventricular Ectopy
6) Pacemaker
7) Medications
8) LVH

Question 3

Prominent T wave

Answer 3

1) Acute myocardial ischemia
2) Hyperkalemia
3) Acute pericarditis
4) LVH
5) BER
6) BBB
7) Pre-excitation syndromes

Question 4

Prominent R wave in V1

Answer 4

1) Posterior MI
2) WPW
3) RBBB or incomplete RBBB
4) Ventricular Ectopy
5) RVH
6) RV strain, acute (eg. PE)
7) HOCM
8) muscular dystrophy
9) dextrocardia
10) misplaced precordial leads

Question 5

Poor R wave Progression

Answer 5

1) Prior Anteroseptal MI
2) LVH
3) High placement of limb leads
4) Normal Variant

Question 6

Low voltage Criteria

Answer 6

[Def’n - QRS in I+II+III<30mm]

Question 7

Low Voltage DDx

Answer 7

"Low Power"
     - myxedema
     - cardiomyopathy (end stage)
     - infiltrative diseases
"Conduction Blockage"
     - fluid (pericardial, pleural)
     - fat (obesity)     
     - air (COPD)

Question 8

Long QT

Answer 8

1) Congenital
2) Drug-induced (sodium channel blocking meds - TCAs/Quinidine)
3) Electrolyte abnormality (Ca/Mg/PO4)
4) MI
5) hypothermia
6) Elevated ICP
7) Hypokalemia (appears widened due to T-U fusion)

Question 9

Rightward Axis

Answer 9

1) LPFB
2) Lateral MI
3) RVH
4) Pulmonary HTN/PE
5) Ventricular Ectopy
6) Hyperkalemia
7) Sodium-channel blocker toxicity
8) Misplaced leads

Question 10

Left ward axis

Answer 10

1) LBBB/LAFB
2) Inferior MI (Q-waves present)
3) Ventricular Ectopy
4) Pacemaker
5) WPW

Question 11

ST elevation in V1

Answer 11

1) LVH
2) LBBB
3) anteroseptal MI
4) RV MI
5) Brugada syndrome
6) Pulmonary Embolus

Question 12

Diffuse ST segment elevation

Answer 12

1) Large STEMI
2) Acute pericarditis
3) BER
4) Ventricular Aneurysm
5) LVH
6) Coronary Vasospasm

Question 13

A fib with slow ventricular response

Answer 13

1) hypothermia
2) medication toxicity (especially digoxin)
3) sick sinus syndrome
4) severe hyperkalemia (consider strongly if highly unusual bradycardia)
* *NB this is a pre-terminal rhythm