ACD 8/18/14“A weird feeling”CARRIE HYDE, PGY 2

UAMS, INTERNAL MEDICINE

Rhythm Strip from OSH

Presenting EKG

CXR

Day 2 EKG

Day 3 EKG

Day 9 EKG

Atrioventricular Block

Atrioventricular (AV) block is defined as a delay or interruption in the transmission of an impulse from the atria to the ventricles due to an anatomical or functional impairment in the conduction system. The conduction disturbance can be transient or permanent, and it can have many causes

Heart block Review

First Degree AV block PR interval greater than 0.20 seconds, Tx: correct electorlytes, caution with

introducing any drug that may slow conduction

Second Degree AV block **Mobitz type I (AKA Mobitz I/Wenchebach): progressive prolongation of PR interval

with dropped beats. Always with a fixed ratio of P waves to QRS waves. Tx: no specific treatment, if symptomatic, can treat with IV atropine or isoproterenol

Mobitz type II (AKA Mobits 2): PR interval remains unchanged prior to the P wave, which suddenly fails to conduct to the ventricles, almost always a disease of the distal conduction system. This may progress to complete heart block Tx: implanted pacemaker

Third Degree (complete) AV block No association between P waves and QRS complexes. Most common etiology is

coronary ischemia. Tx dual chamber pacemaker, emergency tx involves electrical pacing, but AHA recommends giving a trial of atropine (even though it is thought that there will be no effect on third degree heart block)

Summary & Recommendations

Know your AV blocks

Remember there are multiple causes of heart block, like hypothyroidism, that should be investigated