The ECG

The reading method and the classic tracings: blocks, tachycardias, infarction, pericarditis, hyperkalaemia, long QT, WPW and Brugada.

16 pages

ECG tracing

• Atrial fibrillation and atrial flutterThe upper chambers beat chaotically (fibrillation) or in a fast loop (flutter); the ECG shows…
• AV blocks: first, second (Mobitz I and II) and third degreeIn AV block the beat from the upper chambers is delayed or stopped on its way to the lower…
• Broad-complex tachycardia, VF and the arrest rhythmsDangerous fast rhythms that start in the ventricles, and the four rhythms of cardiac arrest…
• Brugada pattern and other sudden-death ECGsSome resting ECGs show a hidden electrical fault that can cause fainting or sudden death in…
• Hyperkalaemia and other electrolyte changesToo much or too little potassium, calcium or magnesium changes the shape of the ECG waves, and…
• Left and right ventricular hypertrophy and atrial enlargementWhen a heart chamber grows thick or large from extra work, the ECG shows taller waves and…
• Narrow-complex tachycardia (SVT)A fast heartbeat that starts above the ventricles; the narrow QRS and the position of the P…
• Paced rhythmsA pacemaker sends small electrical pulses to the heart; each pulse shows as a sharp spike on the…
• Pericarditis on the ECGInflamed lining around the heart lifts the ST segment in almost every lead at once, unlike a…
• Pre-excitation: Wolff–Parkinson–WhiteAn extra electrical wire between the upper and lower heart chambers lets the signal skip the…
• Right and left bundle branch block and fascicular blocksWhen one of the heart's wiring branches is blocked, one ventricle activates late and the QRS…
• Sinus rhythm, sinus tachycardia, bradycardia and arrhythmiaWhen the heart's own pacemaker sets the beat it is sinus rhythm; it can be fast, slow or vary…
• STEMI and its territories, and STEMI mimicsA blocked heart artery lifts the ST segment in the leads that face the dying muscle; the leads…
• The ECG in pulmonary embolism, hypothermia and digoxin effectA clot in the lungs, a dangerously low body temperature and the heart drug digoxin each leave…
• The long QT intervalThe heart takes too long to recharge after each beat, which can set off a twisting, fast…

Interpretation

• Reading an ECG step by stepA fixed order for reading a heart tracing, so that the rate, rhythm, conduction and the shape of…

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Educational content; it does not replace supervised hands-on training, your institution's protocols or a prescriber's order. A procedure is learnt with a teacher and done only once you are trained to do it.

Representative model, for educational purposes only.