Atrial fibrillation with slow ventricular response

ECG Quiz 5

Atrial fibrillation with slow ventricular response
Atrial fibrillation with slow ventricular response

Atrial fibrillation is characterised by the absence of P waves and presence of fibrillatory waves. If the fibrillary waves are more than 1 mm it is known as coarse atrial fibrillation and it indicates atrial enlargement. In fine atrial fibrillation, the fibrillary waves are less than 1 mm in amplitude and may be hardly visible in certain leads which are perpendicular to the axis of the waves. Slow ventricular response can occur due to the effect of drugs like digoxin, beta blockers and verapamil which suppress the AV nodal conduction so that more impulses are blocked in the AV node. It can also occur in structural nodal disease or sick sinus syndrome along with disease of the AV node.

In addition, there is mild ST segment depression in inferior and lateral leads and tall R waves in lateral leads.