Impact of Pulmonary Artery-to-Aorta Ratio by CT on the Clinical Outcome in Heart Failure

ABSTRACT Introduction Previous studies have indicated that the ratio of pulmonary artery (PA) to ascending aorta (Ao) diameter as measured by computed tomography (PA/Ao) is strongly associated with pulmonary artery pressure. However, the clinical significance of PA/Ao in heart failure (HF) has not been fully characterized. We sought to investigate the prognostic impact of PA/Ao in HF. Methods Based on the prospective registry of patients admitted to our institution due to acute decompensated HF (ADHF), the records of the consecutive 761 patients admitted between 2011 and 2016 were reviewed. Thoracic computed tomography data during the hospital stays were obtained from 447 patients (median 78 (70–84) years of age; male, 62.2%). The diameters of PA and Ao were measured at the level of PA bifurcation. The subjects were divided into the H group (PA/Ao ≥ 1.0) and the L group (PA/Ao Results There were no significant differences in age, sex or body mass index between the H and L groups. The H group was associated with significantly larger left atrial dimension (LAD), higher tricuspid regurgitation peak gradient (TRPG) and E/e’ (LAD, H, 48 (42–55) mm vs L, 45 (39–50) mm, P P P P P  = 0.02). Age, sex, LAD and TRPG were independently associated with PA/Ao. The primary endpoint, defined as the composite of all-cause death and ADHF rehospitalization during a median of 479 days after discharge, was significantly more common in the H group ( P P  = 0.002). Conclusions PA/Ao is a reliable marker for the prediction of the outcome of patients with ADHF.