Halliday SJ, Hemnes AR, Robbins IM, Pugh ME, Zhao DX, Piana RN, Fong PP, Brittain EL. Prognostic value of acute vasodilator response in pulmonary arterial hypertension: beyond the "classic" responders. The Journal of heart and lung transplantation : the official publication of the International Society for Heart Transplantation. 2015 Mar;34(34). 312-8. PMID: 25577565 [PubMed] PMCID: PMC4380573 NIHMSID: NIHMS640405.
A "classic" response to acute vasodilator testing (drop of >10 mm Hg in mean pulmonary artery pressure [mPAP] to <40 mm Hg) confers an excellent prognosis in patients with idiopathic pulmonary arterial hypertension (IPAH) and identifies candidates for treatment with calcium channel blockers (CCB). Little is known about vasodilator responsiveness (VR) in other types of PAH, or about outcomes in patients with a significant but "non-classic" decrease in mPAP. We hypothesized that VR occurs in non-idiopathic PAH and non-classic VR portends a better prognosis than no VR in PAH.