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

Abstract

Abstract Background Pulmonary hypertension (PHT) is known to complicate left heart diseases (LHD) including left sided valvular pathologies such as aortic regurgitation (AR). However, there is a paucity of data on the prognostic importance of PHT in AR patients. Purpose We aimed to describe the prevalence and prognostic importance of PHT in adults with "isolated" ≥ moderate AR. 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%, with moderate or greater AR and without severe aortic stenosis or prior aortic valve replacement, were included (n= 8392). These subjects were then categorised according to their eRVSP. The relationship between PHT severity and mortality outcomes were evaluated (median follow-up of 3.1 years, interquartile range 1.5-5.7 years). Results Subjects were aged 74±14 years and 58.4% (4901) were female. Overall, 1417 (16.9%) had no PHT (eRVSP<30.00mmHg); and 3253 (38.8%), 2249 (26.9%), 893 (10.6%) and 580 (6.9%) had borderline (30.00-39.99mmHg), mild (40.00-49.99mmHg), moderate (50.00-59.99mmHg) or severe PHT (>60.00mmHg), respectively. Mean eRVSP was slightly higher in females than males (41±13 vs 39±12mmHg, p<0.0001) and increased with age in both sexes. A typical phenotype of "left heart disease" was evident with E:e’ and the proportion of patients with RV functional impairments increasing progressively, from no PHT to severe PHT (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) 1.20, 95% confidence interval 1.06-1.36 in borderline PHT, to aHR3.32, 95%CI 2.85-3.86 in severe PHT) (Figure 1). These trends were maintained on a sensitivity analysis excluding patients with ≥moderate mitral regurgitation (n=6753), though only became significant from mild PHT onwards (aHR 1.13, 95% CI 0.98-1.30 in borderline PHT, to aHR3.51, 95%CI 2.94-4.18 in severe PHT). Using decile distribution of eRVSP a mortality threshold seen from mild PHT onwards (eRVSP 41.36-44.15mmHg; aHR1.41, 95%CI1.17-1.68) (Figure 2). Conclusions In patients with ≥moderate AR, PHT is associated with a progressive risk of mortality, even in those with mild PHT.Adjusted Risk for All-Cause MortalityThreshold for Mortality