Health Dictionary
Reliable, easy-to-read patient information on common medical conditions — written in plain language, free of jargon, and grounded in current evidence. Browse the most frequent diagnoses, understand what they mean for everyday life, and learn which steps and questions help you have a focused conversation with your doctor.
Atrioventricular block classification
Introduction
Overview
Overview
Atrioventricular (AV) block is a medical condition wherein there is a disturbance in the conduction of an electro-cardiac impulse traveling from the atria to the ventricle, as a result of an anatomic or functional aberration in the conduction system. It is classified into three types, which are the first degree AV block, second-degree AV block, and third-degree AV block/complete AV block.
Classification
Classification
- First degree AV block
- Prolongation of PR interval of more than 200 milliseconds
- Second degree AV block also known as Mobitz I and Mobitz II
- Type I AV Block (Wenckebach)
- Progressive prolongation of the PR interval before dropped beat.
- Usually block is in the AV node
- Type II AV Block
- No change in PR interval before dropped beat
- Usually infranodal
- Type I AV Block (Wenckebach)
- Third degree AV block also known as complete heart block
- No relationship between atrial and ventricular activity.
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]; Associate Editor(s)-in-Chief: Edzel Lorraine Co, DMD, MD[2]