A preliminary study of pulmonary vein implant applicability and safety as a potential ablation platform in a follow-up study in pigs.

BACKGROUND: Recurrence of atrial fibrillation after an ablation procedure remains a major problem which emphasizes the need for improved pulmonary vein isolation techniques.

AIMS: The aim of this study was to describe an implantation procedure of a pulmonary vein-stent which may possibly serve as an ablation technique in the future and to examine stent safety in a follow-up study in pigs.

METHODS AND RESULTS: Eight pigs were catheterized and nine self-expanding nitinol stents were implanted through a transfemoral or transatrial approach into the antra of the pulmonary veins. After 3 months' follow-up, the animals were euthanized for further examination. During the follow-up phase, no complications were observed. Absence of thrombus formation or pulmonary vein wall dissection was noticed during anatomical and histological evaluation of the heart-lung packages. All implants were almost completely covered by neo-intima, of which thickness varied between 0.2 and 3.9 mm.

CONCLUSIONS: Stents can safely be positioned and deployed into the antra of the pulmonary veins without any acute or long-term (3 months) adverse effects. In the future, these implants could function as a permanently implanted ablation device and provide new therapeutic strategies for pulmonary vein isolation in patients with atrial fibrillation.