2nd degree atrioventricular block Morbitz type 1

Question 1

What is 2nd degree AVB mobitz type 1 ?

Answer 1

• Electrical impulses from the Sinoatrial (SA) node are delayed in their journey to the atrioventricular (AV) node.
• There is P waves before the QRS complex however the P wave interval gets more delayed with each conduction before it drops a QRS complex.

Question 2

How is 2nd degree AVB mobitz type 1 recognised?

Answer 2

During the drop phase there will be more P waves than QRS complexes.

• PR interval gets more delayed with each conduction.

QRS complex dropped following a P-wave

Question 3

What should I think with 2nd degree AVB mobitz type 1 ?

Answer 3

P wave is walking backwards away from the QRS complex

Question 4

What leads is 2nd degree AVB mobitz type 1 present in?

Answer 4

All leads

You should specifically review LII and V1

Question 5

Signs and symptoms of 2nd degree AVB mobitz type 1 ?

Answer 5

• SHOCK (Pale, cold, clammy skin, hypotension, delayed CRT, tachypnoea, LOC, anxiety.
• Syncope or pre-syncope

Question 6

Significance of 2nd degree AVB mobitz type 1 ?

Answer 6

• Important to detect if the rhythm is 2AVB Mobitz type 1 or Mobitz type 2 as treatment may change locally.