Cavotricuspid‐Dependent Atrial Flutter in Patients With Prior Atriotomy: 12‐Lead ECG Interpretation and Electroanatomical Characteristics

Cavotricuspid-Dependent Atrial Flutter in Patients With Prior Atriotomy Background The aim of this study was to describe the electrocardiogram (ECG) morphology and electroanatomical characteristics of counterclockwise tricuspid annular atrial flutter (CCWTA-AFL) in the patients with prior atriotomy. Methods and Results This retrospective study included 34 patients with CCWTA-AFL after cardiac surgery and 20 patients with typical CCWTA-AFL without prior surgery. For patients in the postsurgical group, 19 had single-loop CCWTA-AFL and 15 had a double loop CCWTA-AFL. For single loop CCWTA-AFL the F-wave in lead I was very flat in l7 of 19 patients. The F-wave morphology in the inferior leads and V1 were found to be similar to typical AFL in 14 of 19 patients. For double loop CCWTA-AFL, F-waves were positive in lead I in 13 out of 15 patients. A long isoelectric activation was measured between F-waves in most of the patients. The presence of isoelectric segments between F-waves suggested a double loop AFL, which had a sensitivity of 86.7% and a specificity of 100%. Moreover, flat F-waves in lead I suggested a single loop AFL, which had a sensitivity of 89.5% and specificity of 86.7%. All patients in the group without prior cardiac surgery had typical ECGs features of CCWTA-AFL. None of the patients showed isoelectric segments between F-waves in the inferior leads. The amplitudes of most of the leads were higher than those for single loop CCWTA-AFL in patients with prior surgery.