title: Usefulness of intravenous adenosine in idiopathic pulmonary arterial hypertension as a screening agent for identifying long-term responders to calcium channel blockers.
abstract: Although intravenous adenosine is recommended for acute vasodilator testing in patients with pulmonary hypertension, long-term outcomes in acute responders treated with calcium channel blockers (CCBs) who are identified by adenosine remain unknown. In this study, the value of adenosine for identifying long-term responders to CCBs was investigated in patients with idiopathic pulmonary arterial hypertension (IPAH). All acute responders were subsequently treated with high-dose CCB monotherapy, and 6-minute walk distances, hemodynamic data, and World Health Organization functional classifications were followed. Nine of 104 patients exhibited an acute response with intravenous adenosine (8.7%, 95% confidence interval 3.2 to 14.2). After 12 months of follow-up, all acute responders were still alive; however, only 6 patients showed sustained hemodynamic improvement (5.8%, 95% confidence interval 2 to 13). Three patients had failed CCB monotherapy and bosentan was added to their treatment. Mean tolerated dose of intravenous adenosine was 142 ± 49 μg/kg/min. No life-threatening adverse events were observed and only 2 patients of the nonresponders exhibited a 20% decrease in mean systemic arterial pressure. In nonresponders, 1- and 3-year survival rates were 89% and 75%, respectively. In conclusion, acute vasodilator testing with intravenous adenosine was safe and able to screen responders to CCB therapy in patients with IPAH. Long-term CCB responders accounted for about 5.8% of patients with IPAH.
authors.affiliation: Department of Respiratory Medicine, First Affiliated Hospital of Nanjing Medical University, Nanjing, China.
authors.forename: Xiang-Rong
authors.initials: XR
authors.lastname: Zuo
authors.forename: Rui
authors.initials: R
authors.lastname: Zhang
authors.forename: Xin
authors.initials: X
authors.lastname: Jiang
authors.forename: Xin-Li
authors.initials: XL
authors.lastname: Li
authors.forename: Feng
authors.initials: F
authors.lastname: Zong
authors.forename: Wei-Ping
authors.initials: WP
authors.lastname: Xie
authors.forename: Hong
authors.initials: H
authors.lastname: Wang
authors.forename: Zhi-Cheng
authors.initials: ZC
authors.lastname: Jing
mesh_terms: D000241:Adenosine; D000328:Adult; D002121:Calcium Channel Blockers / Q000627:therapeutic use*; D015331:Cohort Studies; D065627:Familial Primary Pulmonary Hypertension; D005260:Female; D005500:Follow-Up Studies; D006334:Heart Function Tests; D006439:Hemodynamics / Q000187:drug effects; D006801:Humans; D006976:Hypertension, Pulmonary / Q000175:diagnosis* / Q000188:drug therapy* / Q000503:physiopathology; D008297:Male; D008403:Mass Screening; D012189:Retrospective Studies; D016896:Treatment Outcome; D014665:Vasodilator Agents; D055815:Young Adult
chemical_list: D002121:Calcium Channel Blockers; D014665:Vasodilator Agents; D000241:Adenosine