Prevalence of pulmonary hypertension in aortic stenosis and its influence on outcomes

Abstract

Abstract Background Aortic stenosis (AS) is the commonest valve abnormality in developed countries with increasing prevalence and a long pre-symptomatic phase. Measurable variables are likely important in stratifying risk and potentially guiding management decisions. The significance of Pulmonary Hypertension (PHT) complicating AS is poorly characterised. Purpose We aimed to describe the prevalence and prognostic importance of PHT in a large cohort of adults with at least moderate AS. Methods In this retrospective study, we analysed the National Echocardiography Database of Australia (data from 2000-2019). Adults with an estimated right ventricular systolic pressure (eRVSP), left ventricular ejection fraction (LVEF) >50% and with moderate or greater AS were included (n= 14980). These subjects were then categorised according to their eRVSP. The relationship between PHT severity and mortality outcomes were evaluated (median follow-up of 2.6 years, interquartile range 1.0-4.6 years). Results Subjects were aged 77±13years and 57.4% were female. Overall, 2049 (13.7%), 5085 (33.9%), 4380 (29.3%), 1956 (13.1%) and 1510 (10.1%) patients had no (eRVSP<30.00mmHg), borderline (30.00-39.99mmHg), mild (40.00-49.99mmHg), moderate (50.00-59.99mmHg) and severe PHT (>60.00mmHg), respectively. A echocardiographic phenotype was evident with worsening PHT, showing rising E:e’ ratio and right and left atrial sizes (p<0.0001, for all). After adjustment for age and sex, the risk of long-term mortality increased as eRVSP increased (adjusted hazard ratio (aHR) 1.15, 95% confidence interval 1.05-1.26 in borderline PHT, to aHR3.04, 95%CI 2.74-3.36 in severe PHT) (Figure 1). These trends were maintained on a sensitivity analysis excluding patients with ≥moderate mitral and/or aortic regurgitation (n=12005), (aHR 1.12, 95% CI 1.002-1.24 in borderline PHT, to aHR3.00, 95%CI 2.66-3.39 in severe PHT). A mortality threshold was identified in the 4th decile of eRVSP categories (35.01–38.00mmHg; HR1.20, P=0.005), with risk progressively increasing through to the 10th decile (HR2.95 p <0.0001). Conclusions Both AS and PHT confer an increased risk of mortality as they progress. In this large cohort study, we find that PHT is common in ≥moderate AS and mortality increases as PHT becomes more severe. A threshold for higher mortality lies within the range of "borderline-mild" PHT.Adjusted Risk for All-Cause MortalityThreshold for Mortality