Venous thromboembolism in heart transplant recipients: Incidence, recurrence and predisposing factors

Background A high frequency of venous thromboembolism (VTE) has been observed after lung, kidney, and liver transplantation. However, data about the incidence of this complication among heart transplant (HT) recipients are lacking. Methods We analyzed the incidence, recurrence, and predisposing factors of VTE in a single-center cohort of 635 patients who underwent HT from April 1991 to April 2013. Deep venous thrombosis (DVT) and pulmonary embolism (PE) were considered as VTE episodes. Results During a median post-transplant follow-up of 8.4 years, 62 VTE episodes occurred in 54 patients (8.5%). Incidence rates of VTE, DVT, and PE were, respectively, 12.7 (95% confidence interval [CI], 9.7–16.3), 8.4 (95% CI, 6.0–11.4), and 7.0 (95% CI 4.8–9.7) episodes per 1,000 patient-years. Incidence rates of VTE during the first post-transplant year and beyond were, respectively, 45.1 (95% CI, 28.9–67.1) and 8.7 (95% CI 6.2–11.2) episodes per 1,000 patient-years. The incidence rate of VTE recurrence after a first VTE episode was 30.5 (95% CI, 13.2–60.2) episodes per 1,000 patient-years. By means of multivariable Cox regression, chronic renal dysfunction, older age, obesity, and the use of mammalian target of rapamycin inhibitors were identified as independent risk factors for VTE among HT recipients. Conclusions VTE is a frequent complication after HT, mainly during the first post-operative year. In view of a high recurrence rate, long-term anti-coagulation should be considered in HT recipients who experience a first VTE episode.