Pulmonary Vascular Alterations on CT Imaging and Outcomes in Heart Failure with Preserved Ejection Fraction: a Preliminary Data.

BACKGROUND Pulmonary vascular disease may play an important role in the pathophysiology of heart failure (HF) with preserved ejection fraction (HFpEF). However, no study has demonstrated non-invasive quantification of pulmonary vascular alterations in HFpEF. This study sought to determine the association between pulmonary vascular alterations quantified by chest computed tomography (CT) and clinical outcomes in HFpEF. METHODS AND RESULTS Pulmonary vascular alterations were quantified in 151 patients with HFpEF who underwent non-contrast chest CT by measuring the percentage of total cross-sectional area (CSA) of pulmonary vessels less than 5 mm2 to the total lung area (%CSA<5). We divided the patients by the median value of %CSA<5 (=1.45%) and examined the association between %CSA<5 and a composite outcome of all-cause mortality or HF hospitalization. During a median follow-up of 17.3 months, there were 44 (29%) composite outcomes. Event-rates were significantly higher in patients with higher %CSA<5 than those with lower %CSA<5 (log-rank p=0.02). %CSA<5 was associated with an increased risk of the outcome (hazard ratio [HR] per 1.0% increment, 1.46; 95% confidence interval [CI] 1.06-1.98; p=0.02) in an unadjusted Cox model, and was independently and incrementally associated with the outcome over age, the presence of atrial fibrillation, E/e' ratio, and estimated pulmonary artery systolic pressure (PASP)(global chi-square 17.3 vs. 11.5, p=0.02). CONCLUSIONS Higher %CSA<5 was associated with an increased risk of all-cause mortality or HF hospitalization in patients with HFpEF, with an incremental prognostic value over age, atrial fibrillation, E/e' ratio, and PASP.