Category: Cardiology

Some supraventricular tachycardias can be missed clinically as the AV conduction may not be 1:1 and the heart rate may be in the normal range.

Using nitroglycerine, especially for suspected anterior wall infarction is useful in excluding vasospastic angina.

ECG changes of myocardial ischemia: ST segment depression in subendocardial ischemia, ST segment elevation in transmural or subepicardial ischemia.

WHO/AHA criteria for acute myocardial infarction, 1950: cardiac pain > 30 min, ST elevation in 2 or more contiguous leads, rise and fall of biomarkers.

Electrical axis of the heart: mean ventricular electrical activity is represented by the mean electrical axis of the QRS.

Variants of normal electrocardiogram: J point elevation and juvenile T inversion are normal variants often seen in ECGs of younger individuals.

Modifications of ECG recording: Mason-Likar torso leads, EASI 5 lead system and 15 lead ECG are some of the modifications.

Dual chamber pacemaker with leads seen on a chest x-ray PA view.

Dressler beat, named after William Dressler from Poland, is a fusion beat interrupting ventricular tachycardia.

Tracings from an electrophysiological study (EPS) with intracardiac and surface electrocardiograms showing atrial pacing with 2:1 AV block