Left atrial and pulmonary vein macroreentrant tachycardia associated with double conduction gaps: a novel type of man-made tachycardia after circumferential pulmonary vein isolation.

BACKGROUND

The macroreentrant tachycardia that involves the left atrium (LA) and the pulmonary veins (PVs) after atrial fibrillation (AF) ablation has not been described.

OBJECTIVE

To clarify the mechanism and electrophysiological characteristics of this tachycardia.

METHODS AND RESULTS

Eight patients presented with recurrent regular tachycardia after the initial procedure, which consisted of two circular linear lesions around the ipsilateral PVs. Clinical tachycardia with a cycle length of 297 +/- 38 ms presented as persistent in six and paroxysmal in two patients. During tachycardia, PV activation with one-to-one conduction from the LA to the PV was found via recovered conduction gaps in the previous lesions in all patients. Three-dimensional tachycardia mapping showed a macroreentrant pattern in two and a focal pattern in six patients. In two patients, mapping demonstrated an isthmus within the left common PV in one patient and within the right-sided PVs in another patient. In the remaining six patients with focal pattern, mapping demonstrated earliest atrial activation near the right-sided PV ostium in five patients and near the left-sided PV in one patient. Entrainment mapping showed that the LA and PVs were involved in the reentrant circuit with an isthmus between the two conduction gaps in all eight patients. The tachycardias were successfully terminated with a single radiofrequency application. No AT recurred during follow-up (12 +/- 9 months) in all patients.

CONCLUSIONS

The LA-PV macroreentrant tachycardia involves the LA, PV, and the two conduction gaps in the previous lesions. Entrainment mapping is necessary to make the diagnosis. Ablation of this tachycardia can be facilitated by closing the conduction gaps.