Circadian rhythms are cycles in the body that occur roughly across 24 hours. In humans, circadian rhythms cause physical and mental changes in the body, including feelings of wakefulness and sleep.

Is there a simple way to differentiate a supraventricular tachycardia from a ventricular, wide QRS tachycardia on a rhythm strip? The simplest initial approach is to look at the lead with the most ...

Paired narrow QRS complexes, each preceded by a P wave, certainly raise the possibility of atrial bigeminy. But there are other causes of paired QRS complexes during sinus rhythm. One should look ...