Learning Heart Arrythmias part 03

Posted by e-Medical PPT Sunday, June 20, 2010
Atrioventricular block occurs when the atrial depolarization fail to reach the ventricles or when atrial depolarization is conducted with a delay. Three degrees of AV block are recognized.
First-degree AV block consists of prolongation of the PR interval on the electrocardiogram (ECG) (less than 0.20 s in adults and less than0.16 s in young children)
Second-degree AV block
Mobitz I second-degree AV block (Wenckebach block) consists of progressive prolongation of the PR interval with the subsequent occurrence of a single nonconducted P wave that results in a pause.
Mobitz II second-degree AV block is characterized by a constant PR interval followed by sudden failure of a P wave to be conducted to the ventricles, such that either an occasional dropped P wave or a regular conduction pattern of 2:1 or 3:1.
Third-degree AV block is diagnosed when no supraventricular impulses are conducted to the ventricles. P waves on the rhythm strip reflect a sinus node rhythm independent from QRS electrocardiographic wave complexes.The QRS complexes represent an escape rhythm, either junctional or ventricular.

Related Posts Plugin for WordPress, Blogger...

0 Responses to Learning Heart Arrythmias part 03

Post a Comment

Share This


Subscribe by E-mail & receive updates your inbox!
Enter your email address:

Follow Us on Facebook

Blog Archive