Chronic thromboembolic pulmonary hypertension (CTEPH), World Health Organization (WHO) Group IV PH, occurs between 2-4% of patients after acute pulmonary embolism and is associated with a high mortality rate if untreated. While Pulmonary endarterectomy (PEA) is the mainstay surgical therapy that may potentially be curative, Riociguat (RIO) is the only approved drug for this group of patients, but only if CTEPH is considered inoperable or persistent/recurrent CTEPH after PEA. In the real world however, RIO is commonly used for symptomatic CTEPH while patients are awaiting surgery/surgical assessment. We describe our experience with RIO in CTEPH since its approval.
Retrospective study. We identified all CTEPH patients (n=6) since Jan 2014 from our PH database. Only 4 of 6 patients were treated with RIO.
Baseline characteristics, Demographics, Hemodynamics and outcomes tabulated in Table 1. Improvement in shortness of breath (SOB) was achieved in all 4 patients as early as 2 months of therapy. The patients who declined PEA has multiple other comorbidities. Patient 1 has severe Bullous emphysema (FEV1 34% predicted, DLCO 24%) and Patient 2 has severe idiopathic gastroparesis as well as stage IV chronic renal failure. Patient 3 underwent successful curative PEA and Patient 4 has very severe disease and is awaiting surgical assessment for PEA.
Riociguat appeared to be effective in improving symptoms (SOB) in patients with CTEPH as early as 2 months and was also well tolerated. Therefore, it may be considered as bridging therapy as well while a patient is awaiting surgery/surgical assessment.