Cardiology In Critical Care

Arrhythmia Recognition

Atrial Flutter

Impulses originate in an atrial pacemaker at a rate 240-340/min but some of them are blocked regularly at the AV junction.  Atrial activity is represented by sawtooth-like deflections (F waves) not separated by an isoelectric segment and best seen in L2, L3 and AVF.  Usually only every second F is conducted to the ventricles (2:1 AV block) with the resulting ventricular rate half the atrial rate; rarely the AV conduction is 3:1, 4:1, 1:1 or variable.  Vagal stimulation may have no effect or slow ventricular rate by increasing AV block or terminate flutter.  Exercise increases HR by decreasing the block.

There have been Visitors to this website.

Return to Nurse Bob's™ Page