In mode switching, if rapid atrial activity is sensed ... a class III indication for pacing. [33] However, in some patients a markedly prolonged PR interval (usually >0.30 sec) can be associated ...

has been found to increase the risk of developing atrial fibrillation, the need for a pacemaker, and premature death. This finding indicates that a prolonged PR interval is an important marker of ...

In this instance, the P wave morphology (normally generated when the SA node fires causing atrial depolarizaion ... but PR interval will be short (< 0.12 ms). If the pacemaker occurs at the ...

the atrial rate, (4) the sensitivity of the AV node and (5) the background sympathetic activity. Vagally induced AV block may be followed by either a shorter or longer PR interval and rarely by an ...

The three irregularly irregular rhythms are atrial fibrillation ... degree AV block that can be type I or type II. If the PR interval of the conducted beat is prolonged and the QRS complex ...

Objectives: To determine risk factors for cardiac complications in patients with myotonic dystrophy, and to determine whether permanent cardiac pacemakers may be beneficial in the treatment of ...