Pulmonary artery compliance is associated with mortality but lacks predictive utility.

Background: Pulmonary artery compliance has physiologic appeal in pulmonary hypertension, but its clinical relevance remains in question. Methods: Adults undergoing right heart catheterization 2005-2019 at University of Pittsburgh Medical Center were included. For association analysis, Cox proportional hazards and linear tail-restricted cubic spline models were used to analyze the relationship between pulmonary artery compliance and mortality. The adjusted hazard for mortality in low ( Results: Among 12,866 patients with 68,444 person-years of follow-up, there were 4946 deaths. Mortality risk progressively increased with declining pulmonary artery compliance. Low pulmonary artery compliance was associated with a 54% increased hazard of death (HR 1.54; 95%CI 1.45 - 1.61, p<0.001) in adjusted Cox models. However, removal of pulmonary artery compliance from full predictive Cox models did not substantially diminish predictive performance for mortality on hold-out testing data (mean Harrell's Concordance Index 0.703 versus 0.704, p=0.541). Conclusions: Although low pulmonary artery compliance is associated with increased mortality, inclusion of pulmonary artery compliance in multivariate predictive models does not improve mortality prediction. Pulmonary artery compliance does not substantially contribute to predictive performance for mortality.