Diagnostic criteria

  The ECG shows a sinus like pattern with wide complexes.

  The sinus pattern causes merging of the QRS complex, ST segment and T wave making them indiscernible. Sinus pattern differentiates ventricular flutter from ventricular tachycardia.

  Heart rate is generally above

Clinical significance

  Increased heart rate decreases diastolic filling time, which in turn decreases cardiac output and results in hemodynamic collapse.

  Ventricular flutter is generally observed
for a short time before degenerating into ventricular fibrillation. This makes it difficult to observe this arrhythmia in the outpatient setting.

ECG 1. The left side of the upper tracing shows
ventricular flutter . The QRS complexes, ST segment and T waves are not
discernible. The arrhythmia has a sinus pattern. On the right side of the tracing, ventricular flutter is seen to degenerate into
ventricular fibrillation . Ventricular fibrillation is a chaotic rhythm and none of the complexes look like each other.
At the end of the tracing , the patient was defibrillated with
210 joules .

Click here for a more detailed ECG

ECG 2. The rhythm tracing above is from a patient with acute anterior myocardial infarction and right bundle branch block.
The rhythm is atrial fibrillation. Irregular RR intervals prove that it is NOT ventricular flutter.