Increased thromboembolic events after lung transplantation.

BACKGROUND: Lung transplantation is a good therapeutic option for end-stage lung disease. Data on thromboembolic complications following lung transplantation are scarce. STUDY
OBJECTIVES: To evaluate the incidence of thromboembolic events following lung transplantation, and to determine their possible association with hypercoagulable state.
DESIGN: Retrospective study in a single, tertiary-care, university-affiliated referral center. SUBJECTS AND
METHOD: The records of 70 patients who underwent lung transplantation in our institution between September 1997 and September 2003 were reviewed for thromboembolic complications. Parameters pertaining to risk of thrombophilia were measured in the patients with thromboembolic complications.
RESULTS: Thromboembolic complications developed in 6 of the 70 patients (8.6%) at 4 to 24 months after transplantation: deep vein thrombosis (DVT) in 2 patients, pulmonary embolism (PE) in 1 patient, both DVT and PE in 1 patient, and retinal vein thrombosis in 2 patients. The fibrinogen level was elevated in all six patients, and factor VIII, IX, and/or XI levels were elevated in five patients. Heterozygosity for 5 10-methylene tetrahydrofolate reductase was documented in two patients, and mutation for factor II or factor V-Leiden mutation was found in one patient. Levels of protein C and protein S and activated protein C resistance were within normal range in all patients. Four patients had mildly elevated levels of at least one antiphospholipid antibody; none had a positive lupus anticoagulant test result. Overall, all patients demonstrated abnormalities on hypercoagulability tests.
CONCLUSIONS: Thromboembolic complications occur at a high rate (8.6%) in lung transplant recipients and are associated with abnormalities in hypercoagulability. The cause remains unclear. Our results should prompt a high index of suspicion for these potentially fatal complications, which would lead to early diagnosis and successful treatment.