Bridging with a parenteral anticoagulant is not necessary when initiating DOACs for this indication. ĭirect oral anticoagulants (DOACs) are the preferred agents for ongoing anticoagulant therapy examples include dabigatran (a direct thrombin inhibitor), and apixaban, edoxaban, or rivaroxaban (direct factor Xa inhibitors). Clinical presentations and electrophysiologic features of atypical atrial flutter and other types of atrial tachycardias can overlap. This is a limitation in the mechanistic/anatomic classification scheme, as the exact mechanism can be determined only by electrophysiologic mapping studies and not from the ECG alone. Atypical flutters are seen when the cavotricuspid isthmus is not part of the circuit, and are characterized by a continuously undulating pattern by ECG that does not fit strict criteria for the typical and reverse typical forms of atrial flutter. The other is generally a functional line of block between the venae cavae. One of these boundaries is the tricuspid valve annulus and is fixed or anatomic. The lateral anatomic boundaries are critical to the development and maintenance of the circuit.
TYPICAL ATRIAL FLUTTER FREE
The typical form of atrial flutter is a prototypic macroreentrant arrhythmia, in which the reentrant wavefront travels up the interatrial septum and down the right atrial free wall ("typical" form) or vice versa ("reverse typical" form). This rhythm is closely related to atrial fibrillation. Characteristic features on ECG are negatively directed saw-tooth atrial deflections (f waves) seen in leads II, III, and aVF, with positively directed deflections in lead V1. The term counterclockwise refers to the direction of activation when the tricuspid annulus is viewed en face, whereby activation occurs up the septum, down the right atrial free wall in a counterclockwise fashion. The typical form depends on the so-called cavotricuspid isthmus for part of the circuit: tricuspid annulus as the anterior boundary and the crista terminalis/eustachian ridge as the posterior boundary, as well as the endocardial cavity of the right atrium. It results from organized electrical activity in which large areas of the atrium take part in the reentrant circuit.
Typical atrial flutter (counterclockwise cavotricuspid isthmus-dependent atrial flutter) is a macroreentrant atrial tachycardia with atrial rates usually above 250 bpm up to 320 bpm.
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