Atrial Flutter with High-Degree AV Block and Ventricular Standstill
Sorry for not posting much lately, folks! I guess I’ve just been too busy…! Anyway, hope you like this one. It was brought to me by a colleague who thought I might enjoy it. He was perfectly right about that!
The patient: Elderly male, admitted to the CCU for near syncopes and episodic dizziness. He had a known atrial flutter, and was using betablockers and flecainide. I’m afraid I do not have the full list here, nor the dosages. He was sleeping when this episode occured and didn’t notice anything. He also did not pass out.
EKG description: This is atrial flutter (type 1, counter-clockwise) at approx. 260 bpm, with a high and quite varied degree of atrioventricular block. The lowest F-wave/QRS ratio in the top strip, is 4:1, resulting in a ventricular rate of around 65 bpm. Medications might play a part here, but one would suspect the ratio to be lower at this atrial rate. The long blocked period shows ventricular standstill that lasts for almost 6 seconds. This is of course the reason for his episodic dizziness and near syncopes (I’m surprised he didn’t syncope completely). In the lower strip, the blocked periods get even longer, practically resulting in ventricular standstill. With such persisting absence of AV conduction, normally one would expect a ventricular ectopic focus to take over. This however, did not happen here.
Conclusively, this is atrial flutter with a high-degree atrioventricular block and intermittent episodes ventricular standstill. The patophysiology behind this could be AV-node tissue degeneration over time, leading to progressively increasing level of block.
Leave a Comment December 16, 2009
