The rhythm is either sinus rhythm or not sinus rhythm. Sinus rhythm refers to the origination of the electrical activity coming from the sinus node — also known as the sinoatrial node, or SA node.

The basic rhythm is sinus. Many premature beats are present, which are all preceded by prematurely occurring P waves (marked by x) and are all PACs. The premature P waves shown in Figure 2 are all ...

The rhythm is regular at a rate of 42 beats/min. The first five QRS complexes are wide (0.14 seconds), with no P waves seen before or after. However, a P wave appears immediately before the fifth QRS ...

More than 300 million EKGs (short for electrocardiogram, a test that checks heart rhythm and electrical signals of the heart) are conducted around the world each year, according to a study published ...

There is clearly a tachycardia with narrow QRS complexes indicating a supraventricular rhythm. The clues to the aetiology are the heart rate of almost exactly 150 / min and the saw tooth waves seen ...