QUIZ
1. Right bundle branch block + LPHP
2. Right axis deviation
3. 3rd degree AV block
1. Sinus tachycardia
2. First degree AV block
3. Left bundle branch block
4. Hyperkalemia
1. Atrial fibrillation with a slow ventricular response
2. Digoxin ECG changes
3. Premature supraventricular beat (1st complex on ECG)
1. Non-sustained monomorphic ventricular tachycardia
1.Prolonged QT interval
2. T wave abnormality consistent with acute intracranial pathology
1. Left bundle branch block
2. Cabrera's sign - possible myocardial
infarction Cabrera’s sign is used to diagnose
an acute myocardial infarction in the
setting of a left bundle branch block and
consists of notching at 40 milliseconds in
the upslope of the S wave in lead V3 and
V4. This has a poor sensitivity of 27% for
myocardial infarction
Left Bundle Branch Block (LBBB)
Normal ECG tracing
1. Atrial tachycardia 150/MIN.
1. Atrial flutter with a slow ventricular response
Accelerated idioventricular rhythm( 60-100)
1. Sinus tachycardia
2. Pulmonary embolism (S1Q3T3)
1. Multifocal atrial tachycardia
2. Old inferior myocardial infarction
3. Premature supraventricular beat with aberrancy
1. Accelerated idioventricular rhythm
2. AV disocciation
1. Atrial fibrillation with a slow ventricular response
2. Right bundle branch block
3. Prolonged QT interval (with normal QTc interval)
1. AV Nodal Reentry Tachycardia (AVNRT)
1. Dextrocardia
2. Posterior myocardial infarction
the causes of a R wave being larger than the S wave in lead V1 include
 a posterior myocardial infarction,
 right bundle branch block,
 WPW Type A,
 right ventricular hypertrophy,
 ventricular tachycardia with a right bundle branch block pattern
 isolated posterior wall hypertrophy (can occur with Duchenne's muscular dystrophy).
1.Premature ventricular contractions
2. Non-specific ST-T wave abnormalities, consider digoxin effect
Hypertrophic obstructive cardiomyopathy (HOCM)
Hypertrophic obstructive cardiomyopathy (HOCM) is a pathologic cardiac condition in which the interventricular septum is
abnormally thickened. The classic finding in HOCM is large dagger-like “septal Q waves” in the lateral leads due to the
abnormally hypertrophied interventricular septum. The apical variant of hypertrophic cardiomyopathy does not result in septal
Q waves as the septum is normal in thickness in this condition. The cardiac apex is thickened resulting in diffuse T wave changes
throughout the precordial leads.
1. Atrial fibrillation with an uncontrolled ventricular response
2. ST changes consistent with ischemia or digoxin effect
3. Left axis deviation
4. Left ventricular hypertrophy
1. Sinus tachycardia
2. Right bundle branch block
3. Right axis deviation
ST changes consistent with ischemia - specifically, occlusion of the left main coronary artery
This ECG shows dramatic ST depression that is downsloping consistent with ischemia. The changes are
quite pronounced. One classic teaching helps to diagnose a left main coronary artery occlusion. This is
ST segment elevation in lead aVR greater than the ST elevation in lead V1 along with ST depression in
the precordial leads.
1. Sinus tachycardia
2. Anterior myocardial infarction
3. Left anterior fascicular block
1. Atrial fibrillation with an uncontrolled ventricular response
2. Left bundle branch block
3. Premature ventricular contractions
•Absence of typical RBBB or LBBB morphology
•Extreme axis deviation (“northwest axis”) — QRS is positive in aVR and
negative in I + aVF.
•Very broad complexes (>160ms)
•AV dissociation (P and QRS complexes at different rates)
•Capture beats — occur when the sinoatrial node transiently ‘captures’
the ventricles, in the midst of AV dissociation, to produce a QRS complex
of normal duration.
•Fusion beats — occur when a sinus and ventricular beat coincides to
produce a hybrid complex.
•Positive or negative concordance throughout the chest leads, i.e. leads
V1-6 show entirely positive (R) or entirely negative (QS) complexes, with
no RS complexes seen.
•Brugada’s sign – The distance from the onset of the QRS complex to the
nadir of the S-wave is > 100ms
•Josephson’s sign – Notching near the nadir of the S-wave
•RSR’ complexes with a taller left rabbit ear. This is the most specific
finding in favour of VT. This is in contrast to RBBB,
where the right rabbit ear is taller.
Hypokalemia
1. Ventricular tachycardia
2. Indeterminate axis
1. Normal sinus rhythm
2. T wave abnormality consistent with intracranial process or ischemia (Wellen's phenomenon)
3. Prolonged QT interval
Normal ECG
Ventricular paced rhythm
3. Anterior myocardial infarction
Sinus bradycardia
2. Wolff-Parkinson-White (WPW) Syndrome - Type A
Incomplete right bundle branch block
3. Prolonged QT interval
4. Polymorphic ventricular tachycardia (Torsades de Pointes)
1. Sinus tachycardia
2. Left ventricular hypertrophy
2. Two to one AV block (2:1 AV block)
3. Right bundle branch block
4. Left anterior fascicular block
1. Ventricular tachycardia
1. Ventricular fibrillation
1. Sinus bradycardia
2. First degree AV block
3. Digoxin effect
2. T wave abnormality consistent with Wellen's phenomenon
3. Left atrial enlargement
4. Poor R wave progression
1. Sinus tachycardia
2. Right bundle branch block
3. Left anterior fascicular block
4. Premature ventricular contractions - ventricular couplet
5. Premature atrial contraction
6. Left ventricular hypertrophy
2. Left posterior fascicular block
3. Right axis deviation
2. 1st degree AV block
3. Left atrial enlargement
2. Premature atrial contractions - atrial bigeminy
3. Old lateral myocardial infarction
4. Non-specific ST-T wave abnormality
1. Normal sinus rhythm
2. Left ventricular hypertrophy
3. Hyperkalemia
2. 3rd degree AV block
3. Right bundle branch block
4. Left anterior fascicular block
5. Left atrial enlargement
1. Atrial fibrillation with an uncontrolled ventricular response
2. Intermittent right bundle branch block - rate dependent
2. Second degree type I AV block
3. Right bundle branch block
4. Left anterior fascicular block
5. Left atrial enlargement - P-mitrale pattern
2. Anterior myocardial infarction
3. Right bundle branch block
1. Sinus tachycardia
2. S1-Q3-T3 pattern of acute right heart strain (McGinn-White
sign) from pulmonary embolism
2. Pericarditis
1. Atrial fibrillation with an uncontrolled ventricular response
2. Low voltage
3. Electrical alternans
2. Arrhythmogenic right ventricular dysplasia (ARVD) with
epsilon waves
1. Sinus tachycardia
2. ST depression consistent with ischemia
1. Sinus tachycardia
2. Anterior myocardial infarction
3. Hyperacute T wave abnormality
1. Sinus tachycardia
2. Wolff-Parkinson-White Type B
2. Premature ventricular contractions in a pattern of
ventricular bigeminy
1. Atrial fibrillation with a rapid ventricular response
2. Left bundle branch block
. Anterior myocardial infarction versus left ventricular
aneurysm
1. Accelerated junctional rhythm
2. Left axis deviation
3. Poor R wave progression
2. 1st degree AV block
3. Left atrial enlargement
4. Poor R wave progression
1. Sinus bradycardia
2. Inferior myocardial infarction
1. Junctional rhythm
2. Hyperkalemia
2. Right ventricular hypertrophy with strain
3. Right atrial enlargement
4. Right axis deviation
2. Hyperacute T waves consistent with myocardial infarction
This patient had acute chest pains and a normal potassium
level. Subsequently, anterior ST elevation developed.
Hyperacute T waves are the very first sign of a myocardial
infarction,
Anterior myocardial infarction
This ECG shows an anteiroseptal myocardial infarction with
hyperacute T waves and "tombstoning" of the ST segment
1. Bidirectional ventricular tachycardia
2. Digoxin toxicity
Bidirectional ventricular tachycardia is a rare, but
pathognomonic rhythm for digoxin toxicity. There are two
distinct QRS morphologies alternating every other beat
1. Accelerated junctional rhythm
2. Left bundle branch block
3. Chapman's sign indicating possible acute myocardial infarction
Chapman's sign is used to diagnose an acute myocardial infarction in the setting of a left
bundle branch block and consists of a notch in the upslope of the R wave in lead I, aVL or V6.
This has a low sensitivity, but a specificity of about 90%.
2. 1st degree AV block
3. Left atrial enlargement
4. Early repolarization
2. Premature atrial contractions
3. Dextrocardia
4. Right axis deviation
1. Atrial fibrillation with an uncontrolled ventricular response
2. Inferior myocardial infarction
1. Sinus tachycardia
2. 3rd degree AV block
3. Poor R wave progression
2. 2nd degree type I AV block (Wenckebach)
3. Inferior myocardial infarction
2. Left ventricular hypertrophy
3. Right atrial enlargement
4. Left anterior fascicular block
. Atrial fibrillation with a slow ventricular response
2. Digoxin effect
1. Ventricular pacing
2. Atrial fibrillation
. Non-conducted premature atrial contractions (blocked PACs)
1. Sinus bradycardia
2. Old inferior myocardial infarction
1. Sinus tachycardia
2. Right atrial enlargement
3. Non-specific T wave abnormality
4. Baseline wobble artifact
2. Right bundle branch block
3. SVT with aberrancy - rate dependent left
bundle branch block
Using the Brugada criteria, we see that there is no concordance (QRS complex down in V1 and up in V6), the R to S
interval is not greater than 100 ms and there is no AV dissociation that is obvious. We then examine the
morphology criteria when the pattern is that of a left bundle. There is no identifiable Q wave or QS in lead V6
which would have favored VT. The is no wide R wave that is 40 ms or greater in V1 or V2 which would have favored
VT. There is no slur or notch in the downstroke of the S wave in lead V1 or V2. Lastly, the duration of the onset of
the QRS complex to the peak of the S wave is not > 60 ms.
1. Sinus tacycardia
2. Wolff-Parkinson-White with alternans
1. Ventricular tachycardia
2. SVT with aberrancy and a rate-dependent left bundle
branch block
1. Ectopic atrial rhythm
2. Left axis deviation
2. First degree AV block
3. Right bundle branch block
4. Left anterior fascicular block
Wolff-Parkinson-White Type B with inferior pseudoinfarction pattern
3. Left axis deviation
Ventricular couplets
3. T wave alternans
2. Right bundle branch block
3. Left anterior fascicular block
4. Two to one AV block (2:1 AV block)
1. Accelerated junctional rhythm
2. Inferior MI
3. Premature ventricular contractions
2. Left atrial enlargement
3. Right bundle branch block
4. Inferior myocardial infarction
1. Ventricular tachycardia
2. Right bundle branch block
3. Left anterior fascicular block
1. Sinus tachycardia
2. Right bundle branch block
3. Left anterior fascicular block
4. Anterior myocardial infarction
2. First degree AV block
1. Ventricular tachycardia
This ECG meets the Brugada criteria for ventricular tachycardia based on the
presence of AV dissociation. Look at the rhythm strip in lead V1 and you will
intermittently see P waves prior the QRS complexes. March them out to see
even more that are consistent. Also, the R-S is about exactly 100 ms in lead V1
and V2 which would meet criteria as well.
2. Non-specific interventricular conduction delay
3. Left atrial enlargement
4. Fusion beats
2. Isolated posterior wall hypertrophy
Without the clinical history this diagnosis is impossible to make based on the
ECG alone. This ECG was from a patient with Duchenne's Muscular Dystrophy
who had posterior wall hypertrophy confirmed on an echocardiogram. This is
one of the causes of an R:S ratio > 1 in lead V1. Other causes of a large R wave
in lead V1 include a right bundle branch block, WPW Type A, right ventricular
hypertrophy and a posterior wall myocardial infarction.

Ecg quiz

  • 1.
  • 2.
    1. Right bundlebranch block + LPHP 2. Right axis deviation 3. 3rd degree AV block
  • 4.
    1. Sinus tachycardia 2.First degree AV block 3. Left bundle branch block 4. Hyperkalemia
  • 5.
    1. Atrial fibrillationwith a slow ventricular response 2. Digoxin ECG changes 3. Premature supraventricular beat (1st complex on ECG)
  • 6.
    1. Non-sustained monomorphicventricular tachycardia
  • 7.
    1.Prolonged QT interval 2.T wave abnormality consistent with acute intracranial pathology
  • 8.
    1. Left bundlebranch block 2. Cabrera's sign - possible myocardial infarction Cabrera’s sign is used to diagnose an acute myocardial infarction in the setting of a left bundle branch block and consists of notching at 40 milliseconds in the upslope of the S wave in lead V3 and V4. This has a poor sensitivity of 27% for myocardial infarction
  • 9.
    Left Bundle BranchBlock (LBBB)
  • 10.
  • 11.
  • 12.
    1. Atrial flutterwith a slow ventricular response
  • 13.
  • 14.
    1. Sinus tachycardia 2.Pulmonary embolism (S1Q3T3)
  • 15.
    1. Multifocal atrialtachycardia 2. Old inferior myocardial infarction 3. Premature supraventricular beat with aberrancy
  • 16.
    1. Accelerated idioventricularrhythm 2. AV disocciation
  • 17.
    1. Atrial fibrillationwith a slow ventricular response 2. Right bundle branch block 3. Prolonged QT interval (with normal QTc interval)
  • 18.
    1. AV NodalReentry Tachycardia (AVNRT)
  • 19.
  • 20.
    2. Posterior myocardialinfarction the causes of a R wave being larger than the S wave in lead V1 include  a posterior myocardial infarction,  right bundle branch block,  WPW Type A,  right ventricular hypertrophy,  ventricular tachycardia with a right bundle branch block pattern  isolated posterior wall hypertrophy (can occur with Duchenne's muscular dystrophy).
  • 21.
    1.Premature ventricular contractions 2.Non-specific ST-T wave abnormalities, consider digoxin effect
  • 22.
    Hypertrophic obstructive cardiomyopathy(HOCM) Hypertrophic obstructive cardiomyopathy (HOCM) is a pathologic cardiac condition in which the interventricular septum is abnormally thickened. The classic finding in HOCM is large dagger-like “septal Q waves” in the lateral leads due to the abnormally hypertrophied interventricular septum. The apical variant of hypertrophic cardiomyopathy does not result in septal Q waves as the septum is normal in thickness in this condition. The cardiac apex is thickened resulting in diffuse T wave changes throughout the precordial leads.
  • 23.
    1. Atrial fibrillationwith an uncontrolled ventricular response 2. ST changes consistent with ischemia or digoxin effect 3. Left axis deviation 4. Left ventricular hypertrophy
  • 24.
    1. Sinus tachycardia 2.Right bundle branch block 3. Right axis deviation
  • 25.
    ST changes consistentwith ischemia - specifically, occlusion of the left main coronary artery This ECG shows dramatic ST depression that is downsloping consistent with ischemia. The changes are quite pronounced. One classic teaching helps to diagnose a left main coronary artery occlusion. This is ST segment elevation in lead aVR greater than the ST elevation in lead V1 along with ST depression in the precordial leads.
  • 26.
    1. Sinus tachycardia 2.Anterior myocardial infarction 3. Left anterior fascicular block
  • 27.
    1. Atrial fibrillationwith an uncontrolled ventricular response 2. Left bundle branch block 3. Premature ventricular contractions
  • 30.
    •Absence of typicalRBBB or LBBB morphology •Extreme axis deviation (“northwest axis”) — QRS is positive in aVR and negative in I + aVF. •Very broad complexes (>160ms) •AV dissociation (P and QRS complexes at different rates) •Capture beats — occur when the sinoatrial node transiently ‘captures’ the ventricles, in the midst of AV dissociation, to produce a QRS complex of normal duration. •Fusion beats — occur when a sinus and ventricular beat coincides to produce a hybrid complex. •Positive or negative concordance throughout the chest leads, i.e. leads V1-6 show entirely positive (R) or entirely negative (QS) complexes, with no RS complexes seen. •Brugada’s sign – The distance from the onset of the QRS complex to the nadir of the S-wave is > 100ms •Josephson’s sign – Notching near the nadir of the S-wave •RSR’ complexes with a taller left rabbit ear. This is the most specific finding in favour of VT. This is in contrast to RBBB, where the right rabbit ear is taller.
  • 33.
  • 34.
  • 35.
    1. Normal sinusrhythm 2. T wave abnormality consistent with intracranial process or ischemia (Wellen's phenomenon) 3. Prolonged QT interval
  • 36.
  • 37.
    Ventricular paced rhythm 3.Anterior myocardial infarction
  • 38.
  • 39.
    Incomplete right bundlebranch block 3. Prolonged QT interval 4. Polymorphic ventricular tachycardia (Torsades de Pointes)
  • 40.
    1. Sinus tachycardia 2.Left ventricular hypertrophy
  • 41.
    2. Two toone AV block (2:1 AV block) 3. Right bundle branch block 4. Left anterior fascicular block
  • 42.
  • 43.
  • 44.
    1. Sinus bradycardia 2.First degree AV block 3. Digoxin effect
  • 45.
    2. T waveabnormality consistent with Wellen's phenomenon 3. Left atrial enlargement 4. Poor R wave progression
  • 46.
    1. Sinus tachycardia 2.Right bundle branch block 3. Left anterior fascicular block 4. Premature ventricular contractions - ventricular couplet 5. Premature atrial contraction 6. Left ventricular hypertrophy
  • 47.
    2. Left posteriorfascicular block 3. Right axis deviation
  • 48.
    2. 1st degreeAV block 3. Left atrial enlargement
  • 49.
    2. Premature atrialcontractions - atrial bigeminy 3. Old lateral myocardial infarction 4. Non-specific ST-T wave abnormality
  • 50.
    1. Normal sinusrhythm 2. Left ventricular hypertrophy 3. Hyperkalemia
  • 51.
    2. 3rd degreeAV block 3. Right bundle branch block 4. Left anterior fascicular block 5. Left atrial enlargement
  • 52.
    1. Atrial fibrillationwith an uncontrolled ventricular response 2. Intermittent right bundle branch block - rate dependent
  • 53.
    2. Second degreetype I AV block 3. Right bundle branch block 4. Left anterior fascicular block 5. Left atrial enlargement - P-mitrale pattern
  • 54.
    2. Anterior myocardialinfarction 3. Right bundle branch block
  • 55.
    1. Sinus tachycardia 2.S1-Q3-T3 pattern of acute right heart strain (McGinn-White sign) from pulmonary embolism
  • 56.
  • 57.
    1. Atrial fibrillationwith an uncontrolled ventricular response 2. Low voltage 3. Electrical alternans
  • 58.
    2. Arrhythmogenic rightventricular dysplasia (ARVD) with epsilon waves
  • 59.
    1. Sinus tachycardia 2.ST depression consistent with ischemia
  • 60.
    1. Sinus tachycardia 2.Anterior myocardial infarction 3. Hyperacute T wave abnormality
  • 61.
    1. Sinus tachycardia 2.Wolff-Parkinson-White Type B
  • 62.
    2. Premature ventricularcontractions in a pattern of ventricular bigeminy
  • 63.
    1. Atrial fibrillationwith a rapid ventricular response 2. Left bundle branch block
  • 64.
    . Anterior myocardialinfarction versus left ventricular aneurysm
  • 65.
    1. Accelerated junctionalrhythm 2. Left axis deviation 3. Poor R wave progression
  • 66.
    2. 1st degreeAV block 3. Left atrial enlargement 4. Poor R wave progression
  • 67.
    1. Sinus bradycardia 2.Inferior myocardial infarction
  • 68.
  • 69.
    2. Right ventricularhypertrophy with strain 3. Right atrial enlargement 4. Right axis deviation
  • 70.
    2. Hyperacute Twaves consistent with myocardial infarction This patient had acute chest pains and a normal potassium level. Subsequently, anterior ST elevation developed. Hyperacute T waves are the very first sign of a myocardial infarction,
  • 71.
    Anterior myocardial infarction ThisECG shows an anteiroseptal myocardial infarction with hyperacute T waves and "tombstoning" of the ST segment
  • 72.
    1. Bidirectional ventriculartachycardia 2. Digoxin toxicity Bidirectional ventricular tachycardia is a rare, but pathognomonic rhythm for digoxin toxicity. There are two distinct QRS morphologies alternating every other beat
  • 73.
    1. Accelerated junctionalrhythm 2. Left bundle branch block 3. Chapman's sign indicating possible acute myocardial infarction Chapman's sign is used to diagnose an acute myocardial infarction in the setting of a left bundle branch block and consists of a notch in the upslope of the R wave in lead I, aVL or V6. This has a low sensitivity, but a specificity of about 90%.
  • 74.
    2. 1st degreeAV block 3. Left atrial enlargement 4. Early repolarization
  • 75.
    2. Premature atrialcontractions 3. Dextrocardia 4. Right axis deviation
  • 76.
    1. Atrial fibrillationwith an uncontrolled ventricular response 2. Inferior myocardial infarction
  • 77.
    1. Sinus tachycardia 2.3rd degree AV block 3. Poor R wave progression
  • 78.
    2. 2nd degreetype I AV block (Wenckebach) 3. Inferior myocardial infarction
  • 79.
    2. Left ventricularhypertrophy 3. Right atrial enlargement 4. Left anterior fascicular block
  • 80.
    . Atrial fibrillationwith a slow ventricular response 2. Digoxin effect
  • 81.
    1. Ventricular pacing 2.Atrial fibrillation
  • 82.
    . Non-conducted prematureatrial contractions (blocked PACs)
  • 83.
    1. Sinus bradycardia 2.Old inferior myocardial infarction
  • 84.
    1. Sinus tachycardia 2.Right atrial enlargement 3. Non-specific T wave abnormality 4. Baseline wobble artifact
  • 85.
    2. Right bundlebranch block 3. SVT with aberrancy - rate dependent left bundle branch block Using the Brugada criteria, we see that there is no concordance (QRS complex down in V1 and up in V6), the R to S interval is not greater than 100 ms and there is no AV dissociation that is obvious. We then examine the morphology criteria when the pattern is that of a left bundle. There is no identifiable Q wave or QS in lead V6 which would have favored VT. The is no wide R wave that is 40 ms or greater in V1 or V2 which would have favored VT. There is no slur or notch in the downstroke of the S wave in lead V1 or V2. Lastly, the duration of the onset of the QRS complex to the peak of the S wave is not > 60 ms.
  • 86.
    1. Sinus tacycardia 2.Wolff-Parkinson-White with alternans
  • 87.
  • 88.
    2. SVT withaberrancy and a rate-dependent left bundle branch block
  • 89.
    1. Ectopic atrialrhythm 2. Left axis deviation
  • 90.
    2. First degreeAV block 3. Right bundle branch block 4. Left anterior fascicular block
  • 91.
    Wolff-Parkinson-White Type Bwith inferior pseudoinfarction pattern 3. Left axis deviation
  • 92.
  • 93.
    2. Right bundlebranch block 3. Left anterior fascicular block 4. Two to one AV block (2:1 AV block)
  • 95.
    1. Accelerated junctionalrhythm 2. Inferior MI 3. Premature ventricular contractions
  • 96.
    2. Left atrialenlargement 3. Right bundle branch block 4. Inferior myocardial infarction
  • 97.
  • 98.
    2. Right bundlebranch block 3. Left anterior fascicular block
  • 99.
    1. Sinus tachycardia 2.Right bundle branch block 3. Left anterior fascicular block 4. Anterior myocardial infarction
  • 100.
  • 101.
    1. Ventricular tachycardia ThisECG meets the Brugada criteria for ventricular tachycardia based on the presence of AV dissociation. Look at the rhythm strip in lead V1 and you will intermittently see P waves prior the QRS complexes. March them out to see even more that are consistent. Also, the R-S is about exactly 100 ms in lead V1 and V2 which would meet criteria as well.
  • 102.
    2. Non-specific interventricularconduction delay 3. Left atrial enlargement 4. Fusion beats
  • 103.
    2. Isolated posteriorwall hypertrophy Without the clinical history this diagnosis is impossible to make based on the ECG alone. This ECG was from a patient with Duchenne's Muscular Dystrophy who had posterior wall hypertrophy confirmed on an echocardiogram. This is one of the causes of an R:S ratio > 1 in lead V1. Other causes of a large R wave in lead V1 include a right bundle branch block, WPW Type A, right ventricular hypertrophy and a posterior wall myocardial infarction.