Answers to the 2014 UMEM ECG Competition
Episode 143

May 26, 2014


SPOILER ALERT:

Test your skills & take the test the before watching this!


Did you miss a few questions?
 
Study the linked content & learn from mistakes
to make sure you don’t miss when it really counts. 
 
Your patients deserve it!

Answers:

  1. B. Pathological Q-waves are at least 40 ms (1mm) in duration (width). They can develop within a couple hours of onset of MI. 

  2. D. ST elevation in II,III,aVF, & V1 + ST depression in lead V2 is highly suggestive of inferior & right ventricular MI. What if V2 has ST depression but V1 & V3 are isoelectric? Do you remember how to diagnose RV MI? How about posterior MI?

  3. A. You can diagnose MI in patients with left bundle branch block. Concordant ST depression ≥ 1mm in V1, V2, or V3 is specific for an acute MI. Make sure you are aware of the Modified Sgarbossa Rule

  4. A. Sometimes ST depression needs to be treated just like ST elevation! Know that de Winter T-waves are suggestive of an acute proximal LAD lesion. 

  5. C. Wellens syndrome is specific for an obstructed LAD lesion. Patients may be asymptomatic, but may benefit from non-emergent catheterization. Check out these other can’t miss cases of Wellens syndrome and make sure you know what’s the opposite of Wellens waves

  6. D. New T-wave inversions in aVL can be the first sign of an inferior STEMI. Subtle reciprocal changes can preceed ST elevations in MI. 

  7. D. Hyperkalemia can cause advanced AV blocks and sinus pauses. When dealing with a bizarre rhythm that is not responding to ACLS, consider hyperkalemia & treat with empiric Ca2+ and NaHCO3-

  8. A. Pericarditis does not give you the check mark sign & PR depression is NOT specific for pericarditis! Know the differences in ECG findings of STEMI vs Pericarditis. 

  9. B. Simultaneous T-wave inversions in anteroseptal and inferior leads = PE until proven otherwise. Do you know the other ECG findings in PE

  10. B. High ventricular voltages and deep narrow Q waves are concerning for hypertrophic cardiomyopathy. Get a doppler echo to make the diagnosis. What else must you look for on the ECG of patients with syncope?

  11. D. Toxic and metabolic derangements can cause really…really wide QRS complexes. Do you remember the differential for wide complex & regular tachycardias

  12. A. Hypercalcemia and Digoxin toxicity may cause short QT intervals. Are you using a systematic and stepwise approach to reading your ECG’s?

  13. D. Accelerated idioventricular rhythms are associated with reperfusion of STEMI. Consider AIVR in patients who are s/p thrombolytics with rhythms that are too slow to be VT. 

  14. D. Procainamide should be your drug of choice in stable patients with atrial fibrillation with WPW. AV nodal blockade can cause ventricular fibrillation and death!

  15. C. Atrial flutter is the most commonly missed tachydysrhythmia. It can cause a regular or irregular rhythm based on its pattern of conduction. Do you know the tips and tricks to avoid misdiagnosing it?

  16. B. In type I, 2nd degree AV block, each atrial impulse has longer and longer conduction time until it fails to conduct to the ventricle. Are you confident in your treatment of unstable bradycardia

  17. B. Patients with syncope and suspected Brugada syndrome need admission for EP testing. 

  18. A. Don’t rule out ventricular tachycardia and call it SVT based on age. Have you heard about the Mattu 2-step algorithm for wide complex tachycardia? Use it to make sure you do not miss this deadly diagnosis. 

  19. C. In type II, 2nd degree AV block, some but not all impulses are transmitted to the ventricles WITHOUT progressive PR interval lengthening. Watch difficult rhythm interpretation made easy for more practice. 

  20. D. The terminal QRS vector in aVR and V6 should always be opposite one another. If the vectors point in the same direction, consider misplaced leads and repeat the ECG! Using a systematic approach and knowing the causes of right axis deviation should have made you consider lead misplacement. 


 
Answers to the 2014 UMEM ECG Competition
Episode 143

May 26, 2014


SPOILER ALERT:

Test your skills & take the test the before watching this!


Did you miss a few questions?
 
Study the linked content & learn from mistakes
to make sure you don’t miss when it really counts. 
 
Your patients deserve it!

Answers:

  1. B. Pathological Q-waves are at least 40 ms (1mm) in duration (width). They can develop within a couple hours of onset of MI. 

  2. D. ST elevation in II,III,aVF, & V1 + ST depression in lead V2 is highly suggestive of inferior & right ventricular MI. What if V2 has ST depression but V1 & V3 are isoelectric? Do you remember how to diagnose RV MI? How about posterior MI?

  3. A. You can diagnose MI in patients with left bundle branch block. Concordant ST depression ≥ 1mm in V1, V2, or V3 is specific for an acute MI. Make sure you are aware of the Modified Sgarbossa Rule

  4. A. Sometimes ST depression needs to be treated just like ST elevation! Know that de Winter T-waves are suggestive of an acute proximal LAD lesion. 

  5. C. Wellens syndrome is specific for an obstructed LAD lesion. Patients may be asymptomatic, but may benefit from non-emergent catheterization. Check out these other can’t miss cases of Wellens syndrome and make sure you know what’s the opposite of Wellens waves

  6. D. New T-wave inversions in aVL can be the first sign of an inferior STEMI. Subtle reciprocal changes can preceed ST elevations in MI. 

  7. D. Hyperkalemia can cause advanced AV blocks and sinus pauses. When dealing with a bizarre rhythm that is not responding to ACLS, consider hyperkalemia & treat with empiric Ca2+ and NaHCO3-

  8. A. Pericarditis does not give you the check mark sign & PR depression is NOT specific for pericarditis! Know the differences in ECG findings of STEMI vs Pericarditis. 

  9. B. Simultaneous T-wave inversions in anteroseptal and inferior leads = PE until proven otherwise. Do you know the other ECG findings in PE

  10. B. High ventricular voltages and deep narrow Q waves are concerning for hypertrophic cardiomyopathy. Get a doppler echo to make the diagnosis. What else must you look for on the ECG of patients with syncope?

  11. D. Toxic and metabolic derangements can cause really…really wide QRS complexes. Do you remember the differential for wide complex & regular tachycardias

  12. A. Hypercalcemia and Digoxin toxicity may cause short QT intervals. Are you using a systematic and stepwise approach to reading your ECG’s?

  13. D. Accelerated idioventricular rhythms are associated with reperfusion of STEMI. Consider AIVR in patients who are s/p thrombolytics with rhythms that are too slow to be VT. 

  14. D. Procainamide should be your drug of choice in stable patients with atrial fibrillation with WPW. AV nodal blockade can cause ventricular fibrillation and death!

  15. C. Atrial flutter is the most commonly missed tachydysrhythmia. It can cause a regular or irregular rhythm based on its pattern of conduction. Do you know the tips and tricks to avoid misdiagnosing it?

  16. B. In type I, 2nd degree AV block, each atrial impulse has longer and longer conduction time until it fails to conduct to the ventricle. Are you confident in your treatment of unstable bradycardia

  17. B. Patients with syncope and suspected Brugada syndrome need admission for EP testing. 

  18. A. Don’t rule out ventricular tachycardia and call it SVT based on age. Have you heard about the Mattu 2-step algorithm for wide complex tachycardia? Use it to make sure you do not miss this deadly diagnosis. 

  19. C. In type II, 2nd degree AV block, some but not all impulses are transmitted to the ventricles WITHOUT progressive PR interval lengthening. Watch difficult rhythm interpretation made easy for more practice. 

  20. D. The terminal QRS vector in aVR and V6 should always be opposite one another. If the vectors point in the same direction, consider misplaced leads and repeat the ECG! Using a systematic approach and knowing the causes of right axis deviation should have made you consider lead misplacement. 


 
When the computer calls it Pericarditis…
Episode 128
February 10, 2014

PR depression is NOT specific for Pericarditis!

Pericarditis vs. STEMI

  • First, make sure you are not missing an acute MI by looking for factors strongly associated with STEMI. Ask yourself:

    • Is there reciprocal ST-segment depression in any leads (except for aVR and V1)? If yes, it’s a STEMI. If not,…

    • Is the ST-segment morphology convex or horizontal? If yes, it’s a STEMI. If not,…

    • Is the STE in lead III> the STE in lead II? If yes, it’s a STEMI.

    • Are there new Q waves? (Need old ECG) If yes, it’s likely a STEMI.

    • Is there a QR-T or check mark sign? If yes, it’s likely a STEMI.

  • If the answer to all those questions is NO, then you can consider the possibility of it being pericarditis.

    • Is there pronounced PR-segment depression in all leads? If so, it’s possibly pericarditis.

    • Is there a pericardial friction rub? If so, it’s possibly pericarditis​.

Do you remember what the check mark sign is? If not check out this previous episode and the links on that page for more cases. 

When the computer calls it Pericarditis…
Episode 128
February 10, 2014

PR depression is NOT specific for Pericarditis!

Pericarditis vs. STEMI

  • First, make sure you are not missing an acute MI by looking for factors strongly associated with STEMI. Ask yourself:

    • Is there reciprocal ST-segment depression in any leads (except for aVR and V1)? If yes, it’s a STEMI. If not,…

    • Is the ST-segment morphology convex or horizontal? If yes, it’s a STEMI. If not,…

    • Is the STE in lead III> the STE in lead II? If yes, it’s a STEMI.

    • Are there new Q waves? (Need old ECG) If yes, it’s likely a STEMI.

    • Is there a QR-T or check mark sign? If yes, it’s likely a STEMI.

  • If the answer to all those questions is NO, then you can consider the possibility of it being pericarditis.

    • Is there pronounced PR-segment depression in all leads? If so, it’s possibly pericarditis.

    • Is there a pericardial friction rub? If so, it’s possibly pericarditis​.

Do you remember what the check mark sign is? If not check out this previous episode and the links on that page for more cases. 

The myth of Medusa & stone heart revealed…
Episode 127
February 3, 2014
Bizarre rhythm? Think about hyperkalemia!
 Knowing all the variations of ECG findings in hyperkalemia saves lives.
 
ECG finding associated with hyperkalemia:
  • Peaked T-waves
  • Widening of the QRS
  • Prolonged PR
  • Flattening and eventual loss for p-waves
  • Advanced AV Blocks and sinus pauses
  • Pseudo ACS, new BBB’s, ST-segment changes
  • Sine wave morphology
In digoxin-intoxicated humans, IV calcium does not seem to cause malignant dysrhythmias or increase mortality. Evidence does not support the historical belief that calcium administration is contraindicated in digoxin-toxic patients. 

 

Reference

Levine M, Nikkanen H, Pallin DJ. The Effects of Intravenous Calcium in Patients with Digoxin Toxicity. J Emerg Med. 2011;40(1):41–46. Pubmed Link

The myth of Medusa & stone heart revealed…
Episode 127
February 3, 2014
Bizarre rhythm? Think about hyperkalemia!
 Knowing all the variations of ECG findings in hyperkalemia saves lives.
 
ECG finding associated with hyperkalemia:
  • Peaked T-waves
  • Widening of the QRS
  • Prolonged PR
  • Flattening and eventual loss for p-waves
  • Advanced AV Blocks and sinus pauses
  • Pseudo ACS, new BBB’s, ST-segment changes
  • Sine wave morphology
In digoxin-intoxicated humans, IV calcium does not seem to cause malignant dysrhythmias or increase mortality. Evidence does not support the historical belief that calcium administration is contraindicated in digoxin-toxic patients. 

Search the site to watch more videos on the bizarre ECG manifestations of #hyperkalemia
 

Reference

Levine M, Nikkanen H, Pallin DJ. The Effects of Intravenous Calcium in Patients with Digoxin Toxicity. J Emerg Med. 2011;40(1):41–46. Pubmed Link

How many ECGs does it take to save a life?
Episode 126
How many ECGs does it take to save a life?
Episode 126
January 27, 2014

When in doubt, get serial ECGs!

  • Reciprocal changes can precede ST-elevation (STE) in MI

  • New TWI in aVL can be the first sign of an Inferior STEMI

  • Get serial ECGs​ in patients with persistant or changing chest pain

  • Check out more cases with #Early reciprocal changes


March 28-31st
Click banner to learn about this awesome upcoming conference
How to avoid misdiagnosis of Mobitz I
Episode 125
January 20, 2014
 

Why does this simple rhythm get misdiagnosed so much?

Don’t trust the computer’s ECG interpretation!

  • Atrial fibrillation should produce an IRREGULARLY irregular ventricular response

  • Always scrutinize lead V1 (closest to the sinus node) for P-waves (atrial activity)

  • Pay close attention to the PR-interval to avoid missing AV blocks

  • If the rhythm is REGULARLY irregular with grouped or “clumped beats” consider:

  1. Premature atrial contractions (PACs)

  2. 2nd degree AV blocks (Mobitz I and Mobitz II)


Want more cases? To review previous episodes & prove your ECG machine wrong, check out #ClumpedBeats

How to avoid misdiagnosis of Mobitz I
Episode 125
January 20, 2014
 

Why does this simple rhythm get misdiagnosed so much?

Don’t trust the computer’s ECG interpretation!

  • Atrial fibrillation should produce an IRREGULARLY irregular ventricular response

  • Always scrutinize lead V1 (closest to the sinus node) for P-waves (atrial activity)

  • Pay close attention to the PR-interval to avoid missing AV blocks

  • If the rhythm is REGULARLY irregular with grouped or “clumped beats” consider:

  1. Premature atrial contractions (PACs)

  2. 2nd degree AV blocks (Mobitz I and Mobitz II)


Want more cases? To review previous episodes & prove your ECG machine wrong, check out #ClumpedBeats

Pacemakers & Acidosis
Episode 124
January 13, 2014

Can pacemakers prevent syphilis? Find out here! 


ECG findings in Hyperkalemia
  • Peaked T-waves
  • Widening of the QRS
  • Prolonged PR
  • Flattening and eventual loss for p-waves
  • Advanced AV Blocks and sinus pauses
  • Pseudo ACS, new BBB’s, ST-segment changes
  • Sine wave morphology
Really wide QRS? Always consider Hyperkalemia/Acidosis & Overdose
Don’t be misled by pacers,which may not work well in acidosis!
Pacemakers & Acidosis
Episode 124
January 13, 2014

Can pacemakers prevent syphilis? Find out here! 


ECG findings in Hyperkalemia
  • Peaked T-waves
  • Widening of the QRS
  • Prolonged PR
  • Flattening and eventual loss for p-waves
  • Advanced AV Blocks and sinus pauses
  • Pseudo ACS, new BBB’s, ST-segment changes
  • Sine wave morphology
Really wide QRS? Always consider Hyperkalemia/Acidosis & Overdose
Don’t be misled by pacers,which may not work well in acidosis!

Knowing this stuff saves lives! For more practice check out…#Hyperkalemia
Himalayan T waves
Episode 123
Himalayan T waves
Episode 123
January 6, 2014

You’ll never look at the mountains the same way again


Himalayan T waves 

  • Giant broad and spiked T waves 
  • Associated with syncope & seizures (due to torsades)
  • Think of congital long QT (Jervell and Lange-Nielsen syndrome)
  • Can also be seen in severe hypokalemia 

Check out this link for a case of congenital long QT with Himalayan T waves and a QTc of 900ms! ​

Also, search these tags for more practice with #T-waves & #Prolonged-QT

Low Voltage QRS Differential
Episode 122
December 30, 2013

Electrocardiographic voltagemia. What’s the significance?

Low Voltage Definition
  • QRS amplitudes in limb leads all < 5 mm or in all chest leads < 10mm (specific definition)
  • QRS amplitudes in I+II+III < 15 mm or V1+V2+V3 < 30 mm (sensitive definition)
Low Voltage QRS Differential
  • “Low Power”
    • Myxedema (severe hypothyroidism)
    • Infiltrative diseases (Amyloid, Sarcoid)
    • End stage cardiomyopathy
  • Conduction blockage
    • Fluid/Effusion (pericardial or pleural)
    • Fat (obesity)
    • Air (COPD)
Don’t rely only on electrical alternans to diagnose pericardial effusions.
Low voltage + Tachycardia = Pericardial effusion until proven otherwise!
Low Voltage QRS Differential
Episode 122
December 30, 2013

Electrocardiographic voltagemia. What’s the significance?

Low Voltage Definition
  • QRS amplitudes in limb leads all < 5 mm or in all chest leads < 10mm (specific definition)
  • QRS amplitudes in I+II+III < 15 mm or V1+V2+V3 < 30 mm (sensitive definition)
Low Voltage QRS Differential
  • “Low Power”
    • Myxedema (severe hypothyroidism)
    • Infiltrative diseases (Amyloid, Sarcoid)
    • End stage cardiomyopathy
  • Conduction blockage
    • Fluid/Effusion (pericardial or pleural)
    • Fat (obesity)
    • Air (COPD)
Don’t rely only on electrical alternans to diagnose pericardial effusions.
Low voltage + Tachycardia = Pericardial effusion until proven otherwise!
T-wave Inversions & ST-Elevation
Episode 120
December 16, 2013

Are you an arrogant schmuck? Find out in 20 minutes!


New T-wave inversion in aVL may be a reciprocal change!

  • Reciprocal changes can precede ST-elevation (STE) in MI
  • New TWI in aVL can be the first sign of an inferior STEMI
  • When in doubt, get serial ECGs
  • STE is complicated
  • Use the J-point, 2 contiguous leads
    • Women: 1.5 mm in V2-V3 and 1 mm in all other leads
    • Men < 40yo: 2.5 mm in V2-V3
    • Men > 40yo: 2 mm in V2-V3 and 1 mm in all other leads
  • ​Pay attention to ST and T-wave morphology
  • Consult cardiology for joint decision-making

Search #Early reciprocal changes to check out similar cases


References

Wagner GS, Macfarlane P, Wellens H, et al. AHA/ACCF/HRS Recommendations for the Standardization and Interpretation of the Electrocardiogram. J Am Coll Cardiol. 2009;53(11):1003–1011. Pubmed Link

Thygesen K, Alpert JS, Jaffe AS, et al. Third Universal Definition of Myocardial Infarction. J Am Coll Cardiol. 2012;60(16):1581–1598. Pubmed Link

O’Gara PT, Kushner FG, Ascheim DD, et al. 2013 ACCF/AHA Guideline for the Management of ST-Elevation Myocardial Infarction. J Am Coll Cardiol. 2013;61(4):e78–e140. Pubmed Link
 
T-wave Inversions & ST-Elevation
Episode 120
December 16, 2013

Are you an arrogant schmuck? Find out in 20 minutes!


New T-wave inversion in aVL may be a reciprocal change!

  • Reciprocal changes can precede ST-elevation (STE) in MI
  • New TWI in aVL can be the first sign of an inferior STEMI
  • When in doubt, get serial ECGs
  • STE is complicated
  • Use the J-point, 2 contiguous leads
    • Women: 1.5 mm in V2-V3 and 1 mm in all other leads
    • Men < 40yo: 2.5 mm in V2-V3
    • Men > 40yo: 2 mm in V2-V3 and 1 mm in all other leads
  • ​Pay attention to ST and T-wave morphology
  • Consult cardiology for joint decision-making

Search #Early reciprocal changes to check out similar cases


References

Wagner GS, Macfarlane P, Wellens H, et al. AHA/ACCF/HRS Recommendations for the Standardization and Interpretation of the Electrocardiogram. J Am Coll Cardiol. 2009;53(11):1003–1011. Pubmed Link

Thygesen K, Alpert JS, Jaffe AS, et al. Third Universal Definition of Myocardial Infarction. J Am Coll Cardiol. 2012;60(16):1581–1598. Pubmed Link

O’Gara PT, Kushner FG, Ascheim DD, et al. 2013 ACCF/AHA Guideline for the Management of ST-Elevation Myocardial Infarction. J Am Coll Cardiol. 2013;61(4):e78–e140. Pubmed Link
 
How to identify MI in paced rhythms
Episode 119
December 9, 2013

Can you read ischemia with a pacemaker???


You can diagnose MI in paced rhythms!

  • Paced rhythms cause ST-segment & T wave changes that can make the identification of acute MI difficult

  • Patients with paced rhythms can be expected to have ST segment & T wave changes that are discordant to the direction of the QRS complex

    • ​This is normal & referred to as the “Rule of Appropriate Discordance”

  • ST-segment deviations that are concordant (in same direction) to the QRS complex are abnormal

Sgarbossa’s criteria can be used to diagnose MI,

in the setting of both paced rhythms & LBBB

Here is what to look for:

     1. Concordant ST elevation ≥ 1mm in any single lead

     2. Concordant ST depression ≥ 1mm in either V1, V2, or V3

     3. Excessively discordant ST elevation ≥ 5mm in any lead


​Do you remember what the Modified Sgarbossa rule is & how to use it?

If not, check out …The Modified Sgarbossa Rule


References

Sgarbossa EB. Recent advances in the electrocardiographic diagnosis of myocardial infarction: left bundle branch block and pacing. Pacing Clin Electrophysiol. 1996;19(9):1370–1379. Pubmed Link

Sgarbossa EB, Pinski SL, Gates KB, Wagner GS. Early electrocardiographic diagnosis of acute myocardial infarction in the presence of ventricular paced rhythm. GUSTO-I investigators. Am J Cardiol. 1996;77(5):423–424. Pubmed Link

Maloy KR, Bhat R, Davis J, Reed K, Morrissey R. Sgarbossa Criteria are Highly Specific for Acute Myocardial Infarction with Pacemakers. West J Emerg Med. 2010;11(4):354–357. Pubmed Link

Schaaf SG, Tabas JA, Smith SW. A patient with a paced rhythms presenting with chest pain and hypotension. JAMA Intern Med. 2013. Epub ahead of print. Pubmed Link
How to identify MI in paced rhythms
Episode 119
December 9, 2013

Can you read ischemia with a pacemaker???


You can diagnose MI in paced rhythms!

  • Paced rhythms cause ST-segment & T wave changes that can make the identification of acute MI difficult

  • Patients with paced rhythms can be expected to have ST segment & T wave changes that are discordant to the direction of the QRS complex

    • ​This is normal & referred to as the “Rule of Appropriate Discordance”

  • ST-segment deviations that are concordant (in same direction) to the QRS complex are abnormal

Sgarbossa’s criteria can be used to diagnose MI,

in the setting of both paced rhythms & LBBB

Here is what to look for:

     1. Concordant ST elevation ≥ 1mm in any single lead

     2. Concordant ST depression ≥ 1mm in either V1, V2, or V3

     3. Excessively discordant ST elevation ≥ 5mm in any lead


​Do you remember what the Modified Sgarbossa rule is & how to use it?

If not, check out …The Modified Sgarbossa Rule


References

Sgarbossa EB. Recent advances in the electrocardiographic diagnosis of myocardial infarction: left bundle branch block and pacing. Pacing Clin Electrophysiol. 1996;19(9):1370–1379. Pubmed Link

Sgarbossa EB, Pinski SL, Gates KB, Wagner GS. Early electrocardiographic diagnosis of acute myocardial infarction in the presence of ventricular paced rhythm. GUSTO-I investigators. Am J Cardiol. 1996;77(5):423–424. Pubmed Link

Maloy KR, Bhat R, Davis J, Reed K, Morrissey R. Sgarbossa Criteria are Highly Specific for Acute Myocardial Infarction with Pacemakers. West J Emerg Med. 2010;11(4):354–357. Pubmed Link

Schaaf SG, Tabas JA, Smith SW. A patient with a paced rhythms presenting with chest pain and hypotension. JAMA Intern Med. 2013. Epub ahead of print. Pubmed Link