The PR interval is the time from the beginning of the P wave (atrial depolarization) to the beginning of the QRS complex (ventricular depolarization). The normal PR interval measures 0.12-0.20 seconds ...

In myocardial excitation, the delay between the excitation of the atria and ventricles is determined by the sum of atrial and atrioventricular nodal conduction. This delay, measured in milliseconds, ...

To the Editor: We read with interest the article titled “Cardiovascular Abnormalities in Late Onset Pompe Disease and ERT” by Forsha et al. 1. Ninety patients were randomized 2:1 to enzyme replacement ...

The diagnosis is normal sinus rhythm, atrial bigeminy, first-degree atrioventricular (AV) block (prolonged AV conduction), and right bundle branch block (RBBB). The rhythm is slightly irregular, with ...

This rhythm strip shows 1:1 conduction of sinus P waves with a normal PR interval at a rate of about 82 beats per minute (RR = 0.72 sec). After the fourth beat there is an isoelectric baseline with no ...