Anticoagulation optimization and clinical impact of post-transplant deep vein thrombosis: clinical impact and a VV-ECMO subgroup analysis.

Post-transplant deep vein thrombosis (DVT) is common after lung transplantation and may contribute to pulmonary embolism and other complications. Whether DVT adversely affects contemporary outcomes and how venovenous ECMO (VV-ECMO) bridging influences early DVT patterns remain unclear. We performed a retrospective single-center study of adult lung transplant recipients (2018-2025). DVT and clinical outcomes were ascertained. Primary analyses compared outcomes and overall survival between recipients with and without DVT in the overall cohort. Secondary analyses assessed DVT-free survival and early anatomic distribution among recipients bridged with preoperative VV-ECMO. Comparisons used Fisher's exact/Mann-Whitney U tests; survival used Kaplan-Meier/log-rank tests. Among 502 recipients, 240 developed DVT. Compared with those without DVT, recipients with DVT had higher rates of pulmonary embolism (22.5% vs. 5.0%, p < 0.0001), acute kidney injury (52.9% vs. 41.2%, p = 0.009), PGD grade 3 (18.3% vs. 10.7%, p = 0.016), longer hospitalization (21 vs. 14 days, p < 0.001), and worse overall survival (HR 2.19, 95% CI 1.49-3.23; log-rank p < 0.001). Of 240 DVT cases, 31 (12.9%) were bridged with VV-ECMO. Within 14 days, upper-extremity DVT was more frequent with VV-ECMO (53.3% vs. 23.5%, p = 0.03), whereas lower-extremity and neck distributions were similar. In multivariable models, operative time was independently associated with DVT (OR 1.18 per hour, 95% CI 1.07-1.31, p < 0.001). Post-transplant DVT is frequent and portends worse outcomes. VV-ECMO bridging is associated with an upper-extremity-predominant DVT pattern but is not an independent DVT predictor after adjustment. Vigilant surveillance is warranted in this high-risk population.