Feasibility of a screening algorithm for chronic thromboembolic pulmonary hypertension: The OSIRIS study

Abstract

IntroductionChronic thromboembolic pulmonary hypertension (CTEPH) is a long-term sequel to pulmonary embolism (PE) whose incidence varies according to different published studies. We have carried out this study to determine its incidence within 2 years after index pulmonary embolism and to study limitations to an early diagnosis. Material and methodsOSIRIS is a multicentre, longitudinal cohort study. Patients were followed for 3, 6, 12, and 24 months after pulmonary embolism using a structured three-step algorithm. A physician-centered questionnaire at least one positive response in a screening proceeded to the second step, transthoracic echocardiography. The third step consisted of ventilation/perfusion lung scintigraphy and right heart catheterisation. A transthoracic echocardiography was performed in patients without positive response in the screening questionnaire after 2 years. CTEPH diagnosis required haemodynamic confirmation by right heart catheterisation and mismatched perfusion defects on lung scintigraphy. ResultsA total of 1191 patients were enrolled in 18 Spanish hospitals. Cumulative CTEPH incidence after 2-years PE was: 2.49 % (95 % CI: 1.68–3.56) and the incidence rate of CTEPH was 1.1 cases per 1000 person-months (95 % CI: 0.725; 1.60). The CTEPH algorithm presented a lack of adherence of 29 %; patient and physician preferences posed barriers to the triage algorithm The screening questionnaire, in patients who completed the follow-up, shows a specificity of 91.3 % (89.0–93.2 %) and negative predictive value of 99.4 % (98.4–99.8 %).. ConclusionsOSIRIS provides practiced clinical based data on the chronic thromboembolic pulmonary hypertension incidence and identified barriers to the implementation of a 3-step triage algorithm for its detection. Clinical trial registrationclinicaltrials.gov identifier: NCT03134898.