More common with the elderly, the matrix of fibrous tissue around the SA node becomes denser, eventually affecting the ability of the SA node to

Located in the upper right atrium near the inlet for the superior vena cava, serves as the predominant pacemaker for the heart with rates usually

A cardiac rhythm that originates from the SA node without the usual regular rhythm indicative of sinus rhythm; this rhythm is common for children and

A cardiac rhythm that originates from the SA node with a rate less than 60/minute. 1. Six Second ECG Guidebook (2012), T Barill, p. 104,

The sinus node is protected by a loose matrix of connective tissue. In advanced age, this loose matrix can become denser. A possible result of

Prolonged pauses in electrical activity – no P waves or QRS complexes – points to trouble at or near the sinus node. The return of

A cardiac rhythm that originates from the SA node with rate of 60-100/minute. Normal Sinus Rhythm: also known as regular sinus rhythm or sinus rhythm,

A cardiac rhythm that originates from the SA node with rates most often 101-180/minute. 1. Six Second ECG Guidebook (2012), T Barill, p. 104, 206

Perhaps the simplest and most common method to determine heart rates involves multiplying the number of QRS complexes found over six seconds by a factor

A Practice Guide to Basic and 12 Lead ECG Interpretation, written by Tracy Barill, 2012 Introduction The ability to correctly interpret an electrocardiogram (ECG), be

A variety of fast and slow channels that are responsible for depolarization in the myocardial cell. 1. Six Second ECG Guidebook (2012), T Barill, p.

The downward placement of the ST segment greater than 1 mm from the isoelectric line; suggestive of cardiac ischemia, but also may point to ventricular

While ST deviations may be a normal occurrence for a subset of the population, most often ST deviation is a sign of either myocardial ischemia,