Abstract 13929: Cardiopulmonary Fitness Index a Novel Index That Improves Prognostic Assessment of Patients With Idiopathic Pulmonary Arterial Hypertension
Background: Peak oxygen consumption or ventilator efficiency, which can better provide prognostic information in patients with idiopathic pulmonary arterial hypertension (IPAH) remains controversial, and studies showed circulatory power and ventilatory power were both variables predictive of prognosis in patients with left heart failure. This study was aimed to assess whether circulatory power and ventilatory power were also variables predictive of prognosis in patients with IPAH, and whether a new variable that was defined as peak oxygen consumption (peak VO2) divided by minute ventilation/carbon dioxide production at anaerobic threshold (VE/VCO2@AT), which we labeled cardiopulmonary fitness index, can better predict prognosis in patients with IPAH.
Methods: Patients with newly diagnosed IPAH underwent symptom-limited cardiopulmonary exercise testing from 1 January 2011 to 1 January 2014 in Fuwai hospital and were followed for up to 66 months for major cardiac events (mortality and lung transplantation). Prognostic value was assessed by survival curves (Kaplan-Meier method) and uni- and multivariate Cox analyses.
Results: One hundred forty-two patients with IPAH (105 female, mean age, 33±11years) were studied. During follow-up (mean: 43±14 months), 25 patients died and 1 patient underwent lung transplantation. In a univariate analysis, peak VO2, VO2@AT , VE/VCO2@AT, cardiopulmonary fitness index , circulatory power, ventilatory power, peak heart rate , NT-ProBNP, pulmonary vascular resistance (PVR), cardiac index (CI ) , WHO functional class were all predictive of cardiac events (all P<0.05). Multivariate analysis demonstrated that only NT-ProBNP and cardiopulmonary fitness index were the indicators of prognosis (chi-square=7.51, P=0.006; chi-square=7.26, P=0.007, respectively).The mortality rates of 1- , 2- and 3-year for patients with cardiopulmonary fitness index≤0.29 mL·kg–1·min–1 were 8.3%, 16.6% and 23.3% respectively.
Conclusions: Cardiopulmonary fitness index, rather than circulatory power or ventilatory power provides prognostic information in patients with IPAH.
Author Disclosures: Y. Tang: None. Q. Luo: None. Z. Zhao: None. L. Gao: None. Q. Jin: None. C. Xiong: None. Z. Liu: None.
- © 2016 by American Heart Association, Inc.