atrial flutter (AF), 1. a type of atrial tachycardia characterized by contraction rates between 230/min and 380/min. Two kinds, typical and atypical, have been identified and are distinguished from each other by their rates and electrocardiographic (ECG) patterns. During typical atrial flutter the atrial rate is between 290/min and 310/min and produces “fence post” or “sawtooth” ECG waves. During atypical atrial flutter the atrial rate is higher, and the ECG waves lack the sawtooth appearance, and are often sinusoidal. For both types, ventricular contractions usually follow atrial contractions in a 1:2, 1:3, 1:4, or variable ratio. It may be cured with electrophysiological radiofrequency ablation. Compare atrial fibrillation. 2. a type of atrial tachycardia characterized by contraction rates between 230/min and 380/min. Two kinds, typical and atypical, have been identified and are distinguished from each other by their rates and electrocardiographic (ECG) patterns. During typical atrial flutter the atrial rate is between 290/min and 310/min and produces “fence post” or “sawtooth” ECG waves. During atypical atrial flutter the atrial rate is higher, and the ECG waves lack the sawtooth appearance, and are often sinusoidal. For both types, ventricular contractions usually follow atrial contractions in a 1:2, 1:3, 1:4, or variable ratio. It may be cured with electrophysiological radiofrequency ablation.
