Characterization of atrial flutter after pulmonary vein isolation by cryoballoon ablation

Pre-Procedural Right Atrial Diameter May Predict the Development of Typical Atrial Flutter in Patients Undergoing Catheter Ablation for Atrial Fibrillation

BACKGROUND

Some patients undergoing catheter ablation for atrial fibrillation may develop typical atrial flutter on follow-up, and a second procedure for typical atrial flutter is often required in such patients. In this study, we aimed to define the variables associated with the development of typical atrial flutter after ablation.

METHODS

One hundred fifty-nine patients who underwent catheter ablation for the first time due to atrial fibrillation and who did not have a previously documented atrial flutter were included in the study. Before ablation, baseline clinical features and echocardiographic parameters were recorded. At the 1st, 3rd, 6th, and 12th months after the procedure, and then annually, the patients were followed up for typical atrial flutter development.

RESULTS

At a mean follow-up of 34.0 (14.0-50.0) months, typical atrial flutter developed in 21 (13.2%) patients. During the follow-up, right atrial diameter was greater in those who developed typical atrial flutter than those who did not [39.0 (38.0-43.0) vs. 36.0 (34.0-39.0) mm, P <.001]. A multiple Cox regression analysis showed that the right atrial diameter was the only independent predictor of typical atrial flutter development (hazard ratio = 1.12, 95% CI: 1.02-1.23, P =.021). A receiver operating characteristic analysis showed that the best cutoff for the right atrial diameter was 38.5 mm to predict typical atrial flutter development (area under the curve = 0.77, 95% CI: 0.67-0.86, sensitivity = 62%, specificity = 75%, P <.001).

CONCLUSION

In patients undergoing catheter ablation for atrial fibrillation, a pre-procedural right atrial diameter measurement may predict typical atrial flutter development at follow-up. In particular, patients with a pre-procedural right atrial diameter ≥39 mm may be at a higher risk for developing typical atrial flutter in the future.

Left-sided Macro-reentry or Right-sided Focal Tachycardia in Patients with Prior Pulmonary Vein Isolation: A Tale of Two Atria

We report on three patients with prior pulmonary vein isolation who presented with atrial tachycardia/atrial flutter. During electrophysiology study, the whole tachycardia cycle length was mapped to the left atrium. Multiple ablation attempts failed to terminate the tachycardia and, subsequently, right atrial mapping revealed a focal early site of origin near the superior vena cava–right atrial junction in two patients and outside the coronary sinus ostium in one patient. In this report, we discuss the probable mechanism of these tachycardias.