20 EKGs You Should Know

Susan P. Torrey, MD, FACEP, FAAEMAssociate Professor of Emergency Medicine

Tufts University School of Medicine

Faculty, Baystate Medical Center

Springfield, Massachusetts

20 EKGs you should know

• Chest pain presentations• Syncope• Palpitations• Metabolic/miscellaneous

1. 45-year-old man with one hour of chest pain radiating to his back.

Isolated posterior wall MI

• Posterior MI usually with inferior• 5% MIs - isolated posterior wall

• Acute posterior wall MI– ST-segment depression V1-3

• As MI evolves:– Upright T waves V1-3

– Tall R waves V1-2

2. 78-year-old dairy farmer with one hour chest pain associated with sweating.

Critical Left Main Artery Disease

• Wellens described association with:– ST-segment depression ≥ 8 leads– ST-segment elevation in lead aVR

• Especially if ST-elevation in aVL

3. 36-year-old woman, 3 weeks post-partum, with 30 min chest pain which has resolved.

Wellens’ warning

• Left anterior descending (LAD)• Associated with either:

– Biphasic T waves anterior leads– Deeply inverted T waves

– Change from initial normal EKG– During pain-free interval– Normal enzymes

four hours after chest pain

4. 53-year-old man with acute MI who received thrombolytic therapy one hour ago.

Accelerated Idioventricular Rhythm

• Beats 1-3 are idioventricular• Note emergence of P before #3• Beats 4-6 are sinus• Beat 7 is a fusion beat

1 2 3 4 5 6 7 8

5. 35-year-old man with chest pressure all day, worse with inspiration and position.

Pericarditis

• Acute phase diffuse ST-elevation– Maintains convex upward shape– Often ST-elevation in II > III (reverse true with MI)

• PR segment depression in II (elevation in aVR)

6. 40-year-old man being evaluated for syncope earlier that day.

Brugada syndrome

• Hereditary sudden death• Sodium-channel mutation

• Downsloping ST in V1-2

• If family hx sudden death, or hx syncope

• EP study and AICD

7. 48-year-old woman with shortness of breath after experiencing syncope.

EKG signs of acute PE

• New RBBB• S1Q3T3

• T wave inversion in V1-3– Correlates with severity of PE

S1Q3T3

Her CT angiogram…

8. 45-year-old man with “worst headache of his life” associated with vomiting.

CNS effect

• Diffuse T wave inversion – impressively deep• Asymmetric with bulging ascending portion• +/- prominent U waves and QT prolongation

Other causes of deep T wave inversion

• Ischemia/subendocardial infarction• Ventricular pacing (memory T waves)• Apical hypertrophic cardiomyopathy• Takotsubo cardiomyopathy• Acute pulmonary embolism

9. 65-year-old woman collapses 3 days after experiencing severe back pain.

Subacute inferior-posterior MI

• Tall R wave in V1– RBBB – QRS > 0.12– WPW, type A – δ wave– RVH – right axis– Old post MI – old inf MI

• Small complexes?– tamponade

10. 75-year-old woman with syncope in church – asymptomatic when lying flat.

Pacemaker failure

• QRS at 24/min• P waves at 75/min• Pacer spikes at 72/min

– Failure of sensing and of capture

↑ ↑ ↑ •↑ • • •

11. 60-year-old man with weakness and “heart racing” – no prior history.

Atrial flutterwith 2:1 AV conduction

• When the rate is 150/minute, always think of 2:1 atrial flutter.

• With AV blocking agents…

12. 36-year-old man with palpitations and near syncope. History of palpitations.

The scariest atrial fib you’ll ever see…

• Avoid typical AV blocking agents– Adenosine– β-blockers– Calcium-channel blockers– Digoxin

Wolff-Parkinson-White Syndrome

• After cardioversion– note δ wave = WPW

• After ablation of bypass– no longer has WPW

13. 28-year-old woman with frequent episodes of “SVT” treated in ED.

Signs of AVRT (WPW)

Prolonged RP interval

QRS alternans

after cardioversion…

14. 50-year-old woman with “heart jumping” but no syncope.

Blocked PAC

The most common cause of a pause in sinus rhythm is a blocked PAC.

15. 68-year-old woman with chronic atrial fibrillation.

Ashman’s phenomenon

• Repolarization proportional to preceding R-R• Thus, with long R-R followed by short R-R

– Portion of conducting system may be refractory (usually RBBB)

• Long…short…weird

V1

16. 25-year-old man with ESRD who missed last hemodialysis session.

Hyperkalemia

• Peaked T waves of hyperkalemia– Symmetrical and narrow-based

• Then ↑ QRS complex and ↓ P wave– sine wave of severe hyperkalemia

17. 70-year-old woman with weakness. Meds include hydrochlorothiazide.

EKG signs of hypokalemia

• U waves appear, and• T waves diminish

May appears as ↑ QT interval• ST-segment depression “rollercoaster”

18. 70-year-old man with metastatic lung cancer who is lethargic.

19. 30-year-old homeless man found outside during winter – unresponsive.

Osborne waves of hypothermia

• Osborne waves appear < 32°C.• Size correlates inversely with temperature.

20. 22-year-old man found unresponsiveby roommate.

EKG signs of TCA toxicity

• Sinus tachycardia• Prolongation QRS complex• Prolongation QTc interval• Rightward shift of terminal 40 msec QRS axis

– Increase amplitude of R wave in aVR

after Rx with NaBicarb…