Within FOCUS, a comprehensive follow-up was programmed for all patients, comprising 18 domains, performed on admission, discharge, and at 3, 6, and 12 months after the event. Of those, medical history, demographic data, clinical examination, computed tomography (CT) scan, transthoracic echocardiography, and laboratory tests were done at first presentation; another echocardiography and event assessment were performed at discharge; and clinical assessments, transthoracic echocardiography, laboratory testing, cardiopulmonary exercise testing (CPET), including a diagnostic workup for CTEPH and an assessment of generic quality of life and disease-specific quality of life were repeated at 3, 6, and 12 months. 3 Taken together, within FOCUS exceptionally high standards of care were practised in centres that had been pre-selected to achieve that as they represent the top experts for CTEPH care in Germany. While this level of care may not be achievable in common practice outside of CTEPH centres, one key finding of FOCUS was that the median time to CTEPH diagnosis after the index PE event was as short as 129 days; 129 days corresponds to 4.3 months, which is significantly shorter than the 14 months in the European CTEPH registry that was recruiting between 2007 and 2009. 4 These data illustrate that early diagnosis of CTEPH (earliest 74 days after the acute event) is possible in settings as practised in FOCUS, and allowed earlier treatments. 5 In that regard, FOCUS pays off, as it may have saved lives and diminished patient suffering. In Europe, the European Union Regulation on Orphan Medicinal Products (1999) defines a rare disease as a disease that affects not more than 1 person per 2000 in the population. 6 While this number does not appear to threaten a health system, cost-of-illness studies in rare diseases have illustrated significant health expenditure in the diagnosis and treatment of rare disease. 7 CTEPH patients who underwent pulmonary endarterectomy (PEA) had a 3-year survival of 89%, compared with 70% for those not operated on [hazard ratio 0.37, 95% confidence interval (CI) 0.24–0.58; P, 0.0001]. 8, 9 Patients who refuse PEA have a lower observed survival rate than those who undergo surgery (5-year survival rate of 53% vs. 83% for those operated). 9 These data illustrate that CTEPH must be treated. While removal of the proximal mechanical component with PEA represents major surgery, one approved and commonly prescribed medical treatment for CTEPH, riociguat, will probably cost approximately US $90 000 annually. 10 In a cost analysis from France, a mean of three stays with balloon pulmonary angioplasty (BPA) sessions per patient were required, with a mean length of stay of 8 days for the first stay and 6 days for successive stays. The total hospital cost attributable to BPA was€ 8764+ 3435 per stay and€ 21 245+ 12843 per patient. 11 Taken together, significant expenditure arises from a single CTEPH diagnosis, taking into account that modern management is multimodal and commonly involves PEA, BPA, and medical treatments together, or in sequence. One important aspect of FOCUS is that there may have been cases of CTEPH prevented by tight follow-ups and rigorous management of anticoagulation after acute PE. In Pengo’s landmark study, 12 cumulative incidence of CTEPH was 3.8%(95% CI 1.1–6.5%) at 2 years. Case number calculations were based on the expectation of a cumulative incidence of CTEPH of only 0.27% at 2 years 13 in a non-expert setting. However, FOCUS authors found a cumulative incidence of CTEPH of 2.3%(95% CI 1.2–4.4%), which is much higher than that …