HOW TO READ ELECTROCARDIOGRAPHY

Department of Cardiology and Vascular MedicineFaculty of Medicine University of Indonesia

National Cardiovascular Center Harapan Kita

V6V5

V4 V3

V2

V1

V6R

V5R

V4R V3R

Midclavicular line

Anterior axillary line

Midaxillary line

Unipolar Precodial (Chest) Leads

Mervin J. Goldman, MD. 11th edition Principles of clinical Electrocardiography. Clinical Professor of Medicine University of California School of Medicine San Francisco @1995-1982

V7 V8 V9 V9RV8RV7R

Horizontal plane of V4-6

Unipolar Precodial (Chest) Leads

Mervin J. Goldman, MD. 11th edition Principles of clinical Electrocardiography. Clinical Professor of Medicine University of California School of Medicine San Francisco @1995-1982

The electrocardiogram(ECG) illustratesconduction of electricalimpulses in the heart.The depolarization of theventricles occurs fromthe endocardium(inside) to theepicardium (outside)[e]The repolarization of theventricles occurs in theopposite direction. [g]

ECG INTERPRETATION

1. RATE 2. RHYTHM 3. AXIS 4. HIPERTROPHIC SIGNS5. MYOCARDIAL INFARCTION6. ARRHYTHMIA

1. RATE

Normal heart rate : 60 – 100 x/minutes• > 100 x/minutes : Sinus Tachycardia• < 60 x/minutes : Sinus Bradicardia

Determination heart rate (normal paper speed 25 mm/s):

• 300

Count number of large square (bold boxes in one R – R’ interval)

• 1500

Count number of small square in one R – R’ intervals

• Number of QRS complex in 6 seconds, multiply by 10

2. RHYTHM

Normal cardiac rhythm : SINUS rhythm

Sinus rhythm characteristics :• Rate 60-100 bpm• Constant R – R interval• Negative P wave in aVR and positive di II• P wave is always followed by QRS complex

3. AXIS

4. HYPERTROPHIC SIGNS

5. MYOCARDIAL INFARCTION

Ischemia Injury Necrosis

ANTERIOR INFARCTION

INFERIOR INFARCTION

POSTEROLATERAL INFARCTION

ARRHYTHMIA

AV BLOCK

WHAT’S WRONG??Lead Error: V1 and V3 are Transposed!In this normal 12-lead ECG the V1 and V3 chest electrodes are interchanged. Experienced ECG interpreters should be able to spot this lead placement error.

DISCUSSION

Sinus arrhythmia

Limb lead reversal

Early repolarization

Subendocardial ischemia. Anterolateral ST-segment depression

Unstable angina

acute anterolateral myocardial infarction

High lateral infarction

Lateral myocardial infarction

 Right ventricular infarction

Acute inferoposterior myocardial infarction

left ventricular aneurysm

Mobitz I

High-grade atrioventricular block

Wolff-Parkinson-White syndrome

Wolff-Parkinson-White syndrome

Atrial fibrillation

Atrial flutter

premature ventricular contraction

Supraventricular tachycardia

Wide complex tachycardia

Ventricular flutter

Idioventricular rhythm