Ventricular flutter is an extremely uncommon arrhythmia which is seldom recognized. It is a sine wave like pattern and associated with severe hemodynamic compromise. It rapidly degenerates into ventricular fibrillation.
Ventricular fibrillation (VF) is a disorganized ventricular rhythm which is immediately fatal unless treated promptly. Ventricular fibrillation can be either coarse fibrillation or fine fibrillation. Coarse ventricular fibrillation is more easily cardioverted than fine VF. Coarse VF degenerates into fine VF if defibrillation is delayed. It is worth remembering that VF also has an electrical axis so that a monitoring lead which is perpendicular to the axis of the VF can record it as ‘asystole’. This was the rationale behind giving a couple of direct current shocks even if the monitor showed asystole. Asystole is a very difficult rhythm to resuscitate from and is most often fatal, while a primary VF has good prognosis if cardioverted promptly.