ECG Practice: Understanding the Basics

Introduction

Electrocardiography (ECG or EKG) is a vital diagnostic tool in cardiology. It records the electrical activity of the heart over a period of time and helps diagnose various cardiac conditions such as arrhythmias, myocardial infarction, and conduction disorders.

How ECG Works

The ECG captures the heart's electrical signals using electrodes placed on the skin. The signals are then displayed as a waveform with different segments representing different phases of the heart's electrical cycle: - P wave: Represents atrial depolarization (the electrical activation of the atria). - QRS complex: Reflects ventricular depolarization (the triggering of ventricular contraction). - T wave: Represents ventricular repolarization (the recovery phase of the ventricles).

Common ECG Abnormalities

1. Arrhythmias: Irregular heart rhythms, such as atrial fibrillation, heart blocks, or ventricular tachycardia.
2. Myocardial Infarction (Heart Attack): ECG changes such as ST-segment elevation (STEMI) or depression may indicate acute coronary syndromes.
3. Conduction Abnormalities: Conditions like bundle branch blocks or atrioventricular (AV) blocks can delay or block electrical signals.
4. Hypertrophy Patterns: Left or right ventricular hypertrophy appears as an increased voltage in the QRS complex.

ECG Interpretation Practice

To enhance your ECG reading skills, follow these steps: 1. Analyze the Heart Rate: Count the R-waves and calculate beats per minute (bpm). 2. Examine the Rhythm: Determine if it is regular or irregular. 3. Assess the Waveforms: Evaluate the P wave, QRS complex, ST segment, and T wave. 4. Compare with Normal Values: Check if the intervals (e.g., PR, QT) are within normal ranges. 5. Look for Pathologies: Identify any signs of ischemia, infarction, hypertrophy, or conduction disorders.

Conclusion

Practicing ECG interpretation takes time and experience. By systematically analyzing ECGs with a structured approach, you can improve your diagnostic accuracy and recognize life-threatening conditions quickly.

Source recommendations

1. American Heart Association (AHA) Guidelines for ECG Interpretation

1. https://www.heart.org/en/health-topics/heart-attack/diagnosing-a-heart-attack/electrocardiogram-ecg-or-ekg
2. https://www.ahajournals.org/doi/10.1161/circulationaha.108.191095
3. https://www.heart.org/-/media/files/affiliates/mwa/kansas-city/kc-cardiac-and-stroke-symposium/2020-event-documents/cardiac-presentations/2-ecg-hockstad.pdf?la=en
4. https://www.ahajournals.org/doi/10.1161/circulationaha.108.191098
5. https://pubmed.ncbi.nlm.nih.gov/19281932/

2. European Society of Cardiology (ESC) Guidelines on ECG Diagnosis

1. https://www.escardio.org/Guidelines/Clinical-Practice-Guidelines/Acute-Coronary-Syndromes-ACS-Guidelines
2. https://academic.oup.com/eurheartj/article/39/21/1883/4939241
3. https://www.escardio.org/Guidelines/Clinical-Practice-Guidelines
4. https://academic.oup.com/eurheartj/article/35/39/2733/853385
5. https://www.escardio.org/Guidelines/Clinical-Practice-Guidelines/Acute-and-Chronic-Heart-Failure