SESSION TITLE: DVT/PE/Pulmonary Hypertension Posters
SESSION TYPE: Original Investigation Poster
PRESENTED ON: Wednesday, October 30, 2013 at 01:30 PM - 02:30 PM
PURPOSE: A classic response to acute vasodilator testing (drop of > 10mmHg in mean pulmonary artery pressure [mPAP] to absolute value of < 40mmHg) confers an excellent prognosis in patients with idiopathic pulmonary arterial hypertension (IPAH) treated with calcium channel blockers (CCB). Little is known about vasodilator responsiveness (VR) in other types of PAH, or about outcomes in PAH patients with a significant but non-classic decrease in mPAP. We hypothesized that VR occurs in non-idiopathic PAH and ‘non-classic’ VR in PAH patients portends a better prognosis than no VR.
METHODS: Acute VR testing with nitric oxide was performed on 157 consecutive patients referred for PH evaluation. Significant but non-classic response was defined as decrease in mPAP > 10mmHg to greater than 40mmHg with preserved cardiac output. Demographics, six minute walk distance (6MWD), and NYHA class were assessed at baseline and the first clinic visit after VR testing.
RESULTS: Thirty-five (22%) patients had a decrease in mPAP > 10mmHg, twenty-one (13%) of whom had a classic response. Among patients with a classic response, 13 (68%) had familial or idiopathic PAH (F/IPAH) and 8 (32%) had connective tissue disease- associated (CTD-PAH). Fourteen (9%) patients had a non-classic response to NO (delta mPAP -15.3±5.2mmHg), consisting of 6 with F/IPAH, 4 with CTD-PAH, 2 with PAH related to congenital heart disease, and 2 with miscellaneous causes. There was no difference in age, gender, or distribution of PAH sub-type between non-classic responders and patients with no response to NO (n = 122). Non-classic responders had similar but non-significant changes in both 6MWD (32±58 m, p = 0.23) and NYHA class (-0.05±0.6, p = 0.80) whereas both improved in non-responders (22±91m, p = 0.04 and -.3±0.6, p <0.001, respectively).
CONCLUSIONS: Patients with non-idiopathic PAH may have a significant VR to NO. There was no improvement in exercise capacity or functional status in patients with a significant but non-classic response to acute VR testing.
CLINICAL IMPLICATIONS: Vasodilator responsive PAH may occur in non-idiopathic PAH, however non-classic VR is not associated with improved patient outcomes compared with non-responsive PAH.
DISCLOSURE: The following authors have nothing to disclose: Stephen Halliday, Anna Hemnes, Ivan Robbins, Evan Brittain
No Product/Research Disclosure Information