Assessment of the quality of anticoagulation management in patients with pulmonary arterial hypertension

Background: Studies assessing the quality of anticoagulation therapy in patients with pulmonary arterial hypertension (PAH) have not been conducted. Objective: To assess the quality of anticoagulation management, the rate of anticoagulation-related complications in patients with PAH, and to identify risk factors for poor anticoagulation. Methods: This observational, retrospective cohort study included patients with confirmed PAH taking a regimen of oral anticoagulants from two centers: Brigham and Women's Hospital in Boston, and Hospital Universitario La Paz in Madrid from January 2009 to August 2015. Efficacy of anticoagulation management and time spent within therapeutic range of study participants were assessed. Results: There were a total of 121 patients with PAH taking oral anticoagulants. Time spent within range (TTR) of those taking vitamin K antagonists (VKAs) was 57.0%. Forty-seven patients (38.8%) had a total of 105 anticoagulation-related events. The odds ratio of having an event in patients with a TTR < 60% was 2.43 (CI 95%, 1.01-5.83; p = 0.046). Possible factors that affected the quality of the anticoagulation were the age, sex, functional capacity, atrial fibrillation and certain pulmonary arterial hypertension specific medications. Conclusion: The quality of targeted anticoagulation in patients with PAH was low. Patients with low TTR were at a higher risk of experiencing anticoagulation-related complications. Specialized anticoagulation centers showed better management of oral anticoagulants.