Long-term outcome of video-assisted thoracoscopic thoracic duct ligation and pericardectomy in dogs with chylothorax: A multi-institutional study of 39 cases.

OBJECTIVE: To evaluate the long-term outcome of video-assisted thoracoscopic (VATS) thoracic duct ligation (TDL) and pericardectomy for treatment of chylothorax in dogs. STUDY DESIGN: Multi-institutional retrospective study. ANIMALS: Thirty-nine client-owned dogs. METHODS: Dogs were included if they had undergone a VATS TDL and pericardectomy and had at least 1-year follow-up or had died within 1 postoperative year. Medical records were evaluated, and recorded data included clinicopathological and diagnostic imaging results, surgical findings, complications, conversion rates, and long-term resolution and recurrence rates. RESULTS: Thirty-nine dogs met the inclusion criteria. Two dogs died intraoperatively; 1 was euthanized after severe restrictive pleuritis was diagnosed intraoperatively, and 1 underwent ventricular fibrillation and cardiac arrest during pericardectomy and could not be resuscitated. Conversion to an open approach was required in 1 of 39 (3%) dogs for TDL and 4 of 36 (11%) dogs for pericardectomy. Overall follow-up time was median 38 months (range, 3-115). Resolution of pleural effusion occurred in 35 of 37 (95%) dogs that survived the perioperative period. Late recurrence of pleural effusion was seen at 12, 12, and 19 months postoperatively in 3 of 35 (9%) dogs that survived the perioperative period and in which chylothorax had initially resolved. CONCLUSION: Successful long-term resolution of chylothorax was seen in a high proportion of dogs that underwent VATS TDL and pericardectomy, although late recurrence was sometimes seen. CLINICAL SIGNIFICANCE: Video-assisted thoracoscopic thoracic duct ligation and pericardectomy are highly successful in dogs with chylothorax. Future studies should evaluate whether pericardectomy is required in dogs without evidence of pericardial disease.