title: Left atrial appendage ligation with single transthoracic port assistance: a study of survival assessment in a porcine model (with videos).
abstract: BACKGROUND
  Left atrial appendage (LAA) exclusion is a well-known procedure for the prevention of stroke in high-risk patients with atrial fibrillation and contraindication to long-term oral anticoagulant therapy.
  
  
  OBJECTIVE
  To evaluate a natural orifice transluminal endoscopic surgery (NOTES) approach for LAA ligation.
  
  
  METHODS
  In 4 acute and 6 survival pigs, we performed LAA by using a forward-viewing, single-channel gastroscope and an operative thoracoscope with a 3-mm working channel (introduced through an 8-mm single transthoracic port).
  
  
  METHODS
  Animal laboratory.
  
  
  METHODS
  The gastroscope was introduced in the thoracic cavity through an esophageal submucosal tunnel. An end loop introduced through the gastroscope was used to legate the LAA. In the survival experiments, the esophageal mucosa was closed using hemoclips.
  
  
  METHODS
  The time, safety, and feasibility of the procedure were recorded. In the survival experiments, endoscopy and postmortem examination were performed on postoperative day 14.
  
  
  RESULTS
  Creation of a submucosal tunnel and esophagotomy were safely performed in all animals without incidents. The mean time for esophagotomy was 17.0 ± 6.3 minutes. Pericardial dissection and LAA ligation were performed in all animals but 1. The mean time for LAA ligation was 34.4 ± 19.1 minutes. No adverse events occurred during the survival period. Endoscopy showed complete esophageal closure. Postmortem examination revealed pleural adhesions on the site of pericardial dissection, and the LAA was fibrotic with the endoloop in place.
  
  
  CONCLUSIONS
  Animal study.
  
  
  CONCLUSIONS
  LAA ligation with single transthoracic trocar assistance is feasible and may be an alternative to anticoagulant therapy or to permanent intracardiac implants in patients with atrial fibrillation.
authors.affiliation: Life and Health Sciences Research Institute, School of Health Sciences, University of Minho, Braga, Portugal.
authors.forename: João
authors.initials: J
authors.lastname: Moreira-Pinto
authors.forename: Aníbal
authors.initials: A
authors.lastname: Ferreira
authors.forename: Alice
authors.initials: A
authors.lastname: Miranda
authors.forename: Carla
authors.initials: C
authors.lastname: Rolanda
authors.forename: Jorge
authors.initials: J
authors.lastname: Correia-Pinto
mesh_terms: D000818:Animals; D020517:Atrial Appendage / Q000601:surgery*; D004947:Esophagus / Q000601:surgery*; D005260:Female; D020699:Gastroscopes; D008026:Ligation; D023421:Models, Animal; D009092:Mucous Membrane / Q000601:surgery; D057605:Natural Orifice Endoscopic Surgery / Q000009:adverse effects / Q000379:methods*; D013552:Swine; D020708:Thoracoscopes; D013997:Time Factors