Riociguat as bridging therapy to pulmonary endarterectomy in patients with chronic thromboembolic pulmonary hypertension: a retrospective cohort study

Abstract

Background: In operable chronic thromboembolic pulmonary hypertension (CTEPH) patients, the utilization of bridging therapy with targeted medications prior to pulmonary endarterectomy (PEA) remains a topic of controversy, despite being common in cases of severe hemodynamic impairment. This study aims to assess the impact of riociguat as a bridging therapy on postoperative hemodynamics and outcomes. Methods: We conducted a retrospective study involving patients undergoing PEA from December 2016 to November 2023. Patients were categorized into two groups based on the use of riociguat before PEA. Pulmonary vascular resistance (PVR) following riociguat administration was assessed pre-PEA. Postoperative outcomes, including mortality, complications, and hemodynamics, were compared, employing propensity score matching analysis. Results: Among the patients, 41.8% (n=56) received riociguat as bridging therapy. In patients with PVR ≥800 dynes sec cm-5, riociguat resulted in a reduction in PVR {1,207 [974-1,698] vs. 1,125 [928-1,486] dynes sec cm-5, P<0.01}, while no significant difference was observed in patients with PVR <800 dynes sec cm-5{641 [474-740] vs. 600 [480-768] dynes sec cm-5, P=0.46}. After propensity score matching, each group included 26 patients. The overall perioperative mortality rate was 2.6%. Postoperative PVR {326 [254-398] vs. 361 [290-445] dynes sec cm-5, P=0.35} was similar in the riociguat group compared to the control group. The incidence of residual pulmonary hypertension (PH) and other postoperative outcomes were also comparable. Conclusions: The use of riociguat as bridging therapy demonstrated hemodynamic improvement before PEA in patients with high preoperative PVR. However, no additional benefits in postoperative mortality or hemodynamics were observed.