EKG TUTORIAL: APPROACH TO INTERPRETATION MARIO L MAIESE D O, FACC, FACOI Clinical Associate Professor UMDNJSOM South Jersey Heart Group September 14-15,

EKG TUTORIAL: APPROACH TO

INTERPRETATION

MARIO L MAIESE D O, FACC, FACOI

Clinical Associate Professor UMDNJSOM

South Jersey Heart Group

September 14-15, 2004

For Questions: email—[email protected]

Rapid Interpretation of EKG’S

Dale Dubin, MD

(required reading before the lecture)

PRIORITIES?

6 Step Approach

1 Rate and Rhythm

2 PR interval

3 QRS interval

4 Signs of MI

5 Signs of Hypertrophy

6 ST/QT/ T wave abnormalities

12-lead EKG Interpretation Six Step Approach

1) rate and rhythm • big box (0.20 sec) rule (for 1,2,3,4,5,& 6 boxes)

300,150,100,75,60,50

--- 60-100 inclusive? YES nl rate

--- < 60 => bradycardia

--- > 100 => tachycardia• unsure of rhythm? YES Arrhythmia ID

6 Step Approach

1 Rate and Rhythm

2 PR interval

3 QRS interval

4 Signs of MI

5 Signs of Hypertrophy

6 ST/QT/ T wave abnormalities

12-lead EKG Interpretation Six Step Approach

2) PR interval [nl 0.12-0.20 inclusive] nl

• PR< 0.12 sec? YES Pre-Excitation Syndrome [PES]; 11 poss Variants;

delta wave with prolonged QRS Wolff-Parkinson- White [WPW] Syndrome

• PR> 0.20 sec [including dropped beats] ? YES differential for prolonged PR

6 Step Approach

1 Rate and Rhythm

2 PR interval

3 QRS interval/ Axis

4 Signs of MI

5 Signs of Hypertrophy

6 ST/QT/ T wave abnormalities

12-lead EKG Interpretation Six Step Approach

3) QRS interval [nl < 0.10 sec]

QRS> 0.10 sec YES differential for wide QRS [bundle branch block{BBB}pattern]

6 Step Approach

1 Rate and Rhythm

2 PR interval

3 QRS interval

4 Signs of MI

5 Signs of Hypertrophy

6 ST/QT/ T wave abnormalities

12-lead EKG Interpretation Six Step Approach

4) signs of transmural [Q wave infarction]?

• Q waves > 0.04 sec in limb leads YES + criteria for MI

• Q waves > 1/4 height of the R wave in the same lead YES + criteria for MI

• Q waves in more than one limb lead YES + criteria for MI

• abnormal R wave progression in precordial [chest] leads YES criteria for MI [age & sites]

6 Step Approach

1 Rate and Rhythm

2 PR interval

3 QRS interval

4 Signs of MI

5 Signs of Hypertrophy

6 ST/QT/ T wave abnormalities

12-lead EKG Interpretation Six Step Approach

5) signs of hypertrophy[increased voltage of QRS complexes]

• Right Ventricular Hypertrophy [RVH]

• Left Ventricular Hypertrophy [LVH]

6 Step Approach

1 Rate and Rhythm

2 PR interval

3 QRS interval

4 Signs of MI

5 Signs of Hypertrophy

6 ST/QT/ T wave abnormalities

12-lead EKG Interpretation Six Step Approach

6) ST/QT/T wave abnormalities• ST seg depression [>1mm]? YES ischemia• ST seg elevation? YES injury• ST scooping? YES digitalis effect• prolonged QT with flat T wave? YES hypo K+• early peaked T waves? YES hyper K+• inverted T waves without Q waves? YES non-

specific*with Hx and + enzymes could be consist with a subendocardial Non-Q wave MI Forward

ARRHYTHMIA IDENTIFICATION

• Rhythm: regular regular regular rhythms

regular irregular premature/missed beats

irregular irregular chaotic rhythms

• P wave

not present absent P waves [escape (late) rhythms]

more P waves than QRSs AV block

ARRHYTHMIA IDENTIFICATION

• QRS Complex

-all narrow nl QRS complexes

-mixed narrow and wide

homogeneous unifocal ventricular ectopy

heterogeneous multifocal ventricular ectopy

-all wide wide QRS complexes

BACK

Differential for Prolonged PR Interval

• P with every QRS 1st degree heart block• progressive PR prolongation with dropped beats 2nd

degree heart block [Mobitz type 1(Wenckebach)]• constant PR with dropped beats 2nd degree heart

block [Mobitz type 11]

• no relationship between p waves and QRS 3rd degree heart block

BACK

Differential for Wide QRS• No P waves

-all negative in V6 => V tach

-bizzare axis => V tach• PR < 0.12 sec => WPW [QRS> 0.10 & < 0.12]• initial QRS peaked [upright] in V1? YES

right bundle branch block (RBBB) [QRS> 0.12]• QRS wide [downward deflection] overall inV1-V6

[QRS> 0.12]? YES left bundle branch block (LBBB)

Differential for Wide QRS

• LBBB pattern [QRS < 0.12] with axis < 45 degrees? YES left anterior hemiblock [LAHB]

• LBBB pattern [QRS < 0.12 with axis > 120 degrees? YES left posterior hemiblock [LPHB]

BACK

Criteria for Infarct Age

• Significant ST segment elevation? YES

acute infarct [days]

• Q waves with inverted T waves ? YES

recent (“subacute”) [days/weeks/months]

• significant Q waves only? YES old [months/years]

BACK

Regular Rhythms

• P wave with every normal QRS => normal sinus rhythm [NSR]--rate 60-100 inclusive

• P wave with every normal QRS/slow [<60] =>

supraventricular bradycardia• P wave with every normal QRS/fast [>100] =>

supraventricular tachycardia• no P waves/wide QRS/fast => V Tachycardia

BACK

Premature/Missed Beats • premature beats [early]

narrow=> PACs/PJCs

wide/same=> unifocal ventricular ectopy

wide/different => multifocal ventricular ectopy

• grouped beats with PR => 2nd deg AV block[1]

• dropped beats without PR => 2nd deg block [2]

• no relationship between P and QRS => 3rd degree AV block

BACK

Chaotic Rhythms

• No P waves [undulating baseline]/irregular ventricular response => atrial fibrillation [AF]

• heterogenious P waves [at least 3 different P wave configurations usually with varying PR intervals => multifocal atrial rhythm [if HR > 100 => multifocal atrial tach

BACK

Rhythms

• Normal

• Abnormal: Arrhythmia

Dysrhythmia

Supraventricular Dysrhythmias

Atrioventricular (AV) Block

Myocardial Infarction

Ventricular conduction abnormalities

Ventricular Dysrhythmias

Pre-Excitation Syndrome (PES)

Experience is a wonderful thing .

It enables you to recognize a mistake when you make it again.

Average but works hard,

Beats

Brilliant but lazy.

1) A 45 yr old black man is noted to have a BP of 150/100. He has been hypertensive the last 10 years. What is the abnormality on the

EKG?

2) What is the cause of the patients’s rapid irregular pulse?

3) What is the cause of the wide QRS complex?

4) The patient complains of “extra” beats. What is the

arrhythmia? Tx?

5) What is the arrhythmia?

6) A patient complains of palpatations. What is the

arrhythmia?

7) The following EKG is obtained during a cardiac arrest.

What is the arrhythmia?

8) What is the cause of the patient’s rapid irregular pulse?

9) How does the rhythm change abruptly in this patient?

10) What arrhythmia and conduction disturbance are

present on this V1 rhythm strip?

11) What arrhythmia is present in this patient?

12) A 50 yr.-old man presents with chest discomfort. The EKG is most consistent with which diagnosis?

Acute inferior wall MIAcute pericarditis

Normal variant “early repolarization” Ventricular aneurysm

13) A 63 yr.-old woman had severe chest pain 6 hours ago.

What does the EKG show?

14) What conduction disturbance is present?

AtherothromboticLesion development

Mechanism of Plaque Disruption in Atherothrombosis (Acute thrombus)

15) A 53 yr old man presents with crushing chest pain. He is hypotensive with jugular

venous distention. What is the EKG diagnosis?

16) A patient has recurrent syncope. What is the diagnosis?

17) The following rhythm strip is obtained post exercise. What is

the diagnosis?

18) What arrhythmia and conduction disturbance are

present?

19) What conduction abnormality is present?

20) What arrhythmia is responsible for the tachycardia in

this patient with underlying chronic lung disease?

21) What dysrhythmia is causing the tachycardia? What other

abnormal finding is present?

22) A 62 year old women presents with the sudden onset of acute crushing chest pain.

What is the diagnosis?

“To look is one thing; To see what you look at is

another, To understand what you see is a

third;To learn from what you

understand is still something else,But to act on what you learn is all

that really matters!”

Be Sincere

Be simple in words, manners and gestures.

Amuse as well as instruct.

If you can make a man laugh you can make him think and believe you.

Time is Up

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Experience is a wonderful thing .

It enables you to recognize a mistake when you make it again.