Typical atrial flutter in humans is the consequence of a stable macro-reentrant circuit
produced by the unique right atrial architecture providing anatomic barriers and functional
blocks to conduction. Mapping studies have indicated that the so-called isthmus between
the inferior aspect of the tricuspid annulus and the ostium of the inferior caval
vein is a critical zone for maintenance of atrial flutter. An anatomically guided
approach with placement of a transmural and contiguous lesion line throughout the
isthmus has established as curative treatment of typical atrial flutter. Electro-physical
criteria indicating complete bidirectional isthmus conduction block after ablation
proved to be superior with respect to redurrences of atrial flutter compared with
the noninducibility criterion. The gold standard for prove of complete conduction
block is the recording of double potentials along the entire isthmus ablation line.
Recently, it proved possible to reduce the period of fluoroscopy during isthmus ablation
by using electro-anatomical mapping.
Atrial flutter - Catheter ablation - Isthmus - Electro-anatomical mapping
