Chronic thromboembolic pulmonary hypertension (CTEPH; World Health Organization (WHO) Group IV pulmonary hypertension (PH)) is a potential complication of acute pulmonary embolism (PE).1,2 CTEPH is a two-compartment disease with (1) an occlusive component that may be amenable to surgical excision with pulmonary thromboendarterectomy (PTE) surgery3 and (2) a small vessel disease and constriction, similar to that in pulmonary arterial hypertension (PAH),4 that may be amendable to vasodilation. Riociguat, a soluble guanylate cyclase stimulator, is the only medical therapy approved by the US Food and Drug Administration for the treatment of patients with CTEPH and is indicated for patients with CTEPH who are inoperable or who have persistent/recurrent CTEPH after surgery.4,5 Administering a treatment for PAH as a bridging therapy to PTE is supported by studies that suggest a reduction in pulmonary vascular resistance (PVR) before surgery may improve the postoperative course.6 Since there is usually a lag time between diagnosis and being seen at a PTE center for surgical evaluation, there is a compelling case to understand whether medical therapy can benefit patients waiting for either surgery or surgical evaluation.
The current case series describes our real-world clinical experience with riociguat in 10 patients with CTEPH, identified from chart review at two PH care centers, who were either awaiting operability assessment or PTE surgery. All patients reached the 2.5 mg TID dose, except for patients 5 and 6, who reached 1.5 mg. Not all patients represented proceeded to successful PTE. No patient received balloon pulmonary angioplasty.