The electrocardiogram (ECG) is a valuable tool for assessing the cardiac conduction system. The measurements routinely obtained with ECG include heart rate, PR interval, QRS duration and the QT ...

The rhythm is irregularly irregular (ie no consistency to the RR intervals). There are three supraventricular rhythms that are irregularly irregular: Sinus arrhythmia, in which there is one P wave ...

A common electrocardiogram finding that has largely been considered insignificant may actually signal an increased risk of atrial fibrillation, the future need for a permanent pacemaker and an ...

If a premature atrial contraction occurs when the AV node has not yet recovered from the refractory period, the PAC will fail to conduct to the ventricles and there will not be a QRS complex ...