Some observations on abnormal rhythms: Part 1

Remember:

A slow regular ventricular rhythm might be due to :

1-Sinus bradycardia.
2-Complete AV block with idioventricualr rhythm.
3-Normal sinus rhythm with 2:1 AV block.
4-Normal sinus rhythm with 2:1 SA block (very rare).
5-Atrial flutter with high grade 4:1 AV block.
6-Sinus default with idionodal escape rhythm
7-Sinus default with idioventricualr escape rhythm.

Causes of IRREGULAR ventricular rhythm:

1-Atrial fibrillation.
2-frequent and irregularly occurring atrial and or ventricular extrasystoles.
3-Atrial flutter with second degree AV blockand varying AV conduction ratios.
4-Paroxysmal atrial tachycardia with variable second degree AV block .
5-Marked respiratory sinus arrhythmia.

"SLOW' atrial fibrillation:

Slow atrial fibrillation usually reflects treatment with digitalis ;
or in the absence of digitalis therapy , a structural nodal disease ( sick sinus syndrome ).
A more correct description is " atrial fibrillation with slow or diminished ventricular response".

Common causes of bigeminal rhythm:

1-alternate ventricular extrasystoles( the commonest cause ).
2-alternate atrial or nodal extrasystoles.
3-any form of 3:2 AV block.
4-atrial flutter with alternating 4:1 and 2:1 AV block.

Category: Cardiology Notes