ACUTE VASOREACTIVITY TESTING DURING RIGHT HEART CATHETERIZATION IN CHRONIC THROMBOEMBOLIC PULMONARY HYPERTENSION: RESULTS FROM THE PULMONARY VASCULAR DISEASE OMICS PROJECT

Abstract

SESSION TITLE: Advances in the Diagnosis and Management of Pulmonary Hypertension SESSION TYPE: Original Investigations PRESENTED ON: October 18-21, 2020 PURPOSE: Chronic thromboembolic pulmonary hypertension (CTEPH) is believed to involve both vascular obstruction and vasoconstriction; hence vasodilators such as riociguat may be beneficial. Acute vasoreactivity testing is seldom performed, so there is limited understanding of frequency and significance of acute response. Systematic vasodilator testing with oxygen and oxygen plus inhaled nitric oxide was performed as part of the Pulmonary Vascular Disease Omics (PVDOMICS) NHLBI project, providing opportunity to examine this issue. METHODS: Patients with CTEPH enrolled in PVDOMICS underwent right heart catheterization including vasodilator challenge with 100% oxygen (02) and 100% oxygen plus 40 PPM of inhaled nitric oxide (02 + NO). Mean pulmonary artery pressure, pulmonary artery wedge pressure, and cardiac output by thermodilution with calculation of pulmonary vascular resistance (PVR) was obtained at baseline and with each intervention. We examined acute vasoreactivity defined as > 20% drop in PVR, > 20% drop in both mPAP and PVR, and as a drop in mPAP > 10 mmHg to a value < 40 mmHg with normal cardiac output. RESULTS: Of the 61 patients who underwent vasoreactivity testing, 32 (52%) were on PH therapy (15 riociguat, 8 PDE5i, 9 other) and 29 (48%) were on no targeted PH therapy. Fourteen (23%) had prior pulmonary thromboendarterectomy, 1 (2%) had prior balloon pulmonary angioplasty. In the overall cohort, mean PVR was 5.49 WU at baseline, 4.81 with 02, and 4.01 with O2 + NO (mean ± SD change from baseline: -1.43 ± 1.32, 26%), p < .0001). In the subset who were on no PH therapy, mean PVR was 6.26 at baseline, 5.75 with 02, and 4.55 with 02 + NO (change from baseline of -1.62 ± 1.36, 26%), p < .0001). Overall, 25 (43%) had > 20% drop in PVR with 02. With 02 + NO, 36 (62%) had > 20% drop in PVR (decline of 1.43 ± 1.32 WU), including 9 (64%) of those with prior thromboendarterectomy and 19 who were on PH therapy. Six (10%) had a drop in mPAP by > 10 mmHg to < 40 mmHg with normal cardiac output. Thirteen (21%) had > 20% drop in both mPAP and PVR, 6 of whom were on no PH therapy and 4 out of 8 (50%) of those who were on PDE5i. Only 2/15 (13%) of those on riociguat had > 20% drop in both mPAP and PVR. CONCLUSIONS: An element of acute vasoreactivity is common in CTEPH including in those with prior pulmonary thromboendarterectomy. The 26% decline in PVR with acute testing for those who were on no PH therapy is similar to what was achieved chronically on average with riociguat in the pivotal randomized study [(29%, 226 dyn.sec.cm -5 = 2.83 WU,) from baseline of 791]. Whether acute vasoreactivity testing is predictive of clinical response to riociguat or other pulmonary vasodilators is worthy of additional investigation. CLINICAL IMPLICATIONS: Vasoconstriction is a significant contributor to the elevation in pulmonary artery pressure and resistance in the majority of patients with CTEPH. DISCLOSURES: No relevant relationships by Erika Berman Rosenzweig, source=Web Response Advisory Committee Member relationship with Liquidia Please note: $1001 - $5000 Added 03/19/2020 by Robert Frantz, source=Web Response, value=Consulting fee Advisory Committee Member relationship with Altavant Please note: $1001 - $5000 Added 03/19/2020 by Robert Frantz, source=Web Response, value=Consulting fee Advisory Committee Member relationship with Actelion Please note: $5001 - $20000 Added 07/16/2020 by Robert Frantz, source=Web Response, value=Consulting fee No relevant relationships by Paul Hassoun, source=Web Response Advisory Committee Member relationship with bayer Please note: $1001 - $5000 Added 04/14/2020 by Anna Hemnes, source=Web Response, value=Consulting fee Advisory Committee Member relationship with Complexa Please note: $1-$1000 Added 04/14/2020 by Anna Hemnes, source=Web Response, value=Consulting fee Advisory Committee Member relationship with United Therapeutics Please note: $1001 - $5000 Added 04/14/2020 by Anna Hemnes, source=Web Response, value=Consulting fee Advisory Committee Member relationship with actelion Please note: $1001 - $5000 Added 04/14/2020 by Anna Hemnes, source=Web Response, value=Consulting fee Scientific Medical Advisor relationship with PHPreMedicine Please note: $1-$1000 Added 04/14/2020 by Anna Hemnes, source=Web Response, value=Ownership interest no disclosure on file for Evelyn Horn; No relevant relationships by Armand Larive, source=Web Response My spouse/partner as a Consultant relationship with Cellectis Please note: >$100000 Added 05/28/2020 by Jane Leopold, source=Web Response, value=Consulting fee no disclosure on file for Franz RIschard; Consultant relationship with Sequana Medical AG Please note: $5001 - $20000 Added 05/28/2020 by Wai Hong Tang, source=Web Response, value=Consulting fee Editor/Author relationship with Springer Nature Please note: $1-$1000 Added 05/29/2020 by Wai Hong Tang, source=Web Response, value=Honoraria My spouse/partner as a Consultant relationship with Cardiac Community Core Lab, LLC Please note: $1001 - $5000 Added 05/28/2020 by Wai Hong Tang, source=Web Response, value=Honoraria