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

Objective Aortic regurgitation (AR) can lead to pulmonary hypertension (PHT). There is a paucity of data on the prognostic importance of PHT in these patients. We therefore aimed to describe the prevalence and prognostic importance of PHT in such patients. Methods In this retrospective study, we analysed the National Echocardiography Database of Australia (data from 2000 to 2019). Adults with an estimated right ventricular systolic pressure (eRVSP), left ventricular ejection fraction (LVEF) >50% and with moderate or greater AR 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, IQR 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, and 3253 (38.8%), 2249 (26.9%), 893 (10.6%) and 580 (6.9%) patients had borderline, mild, moderate and severe PHT, respectively. Mean eRVSP was slightly higher in females than males (41±13 vs 39±12 mm Hg, p<0.0001) and increased with age in both sexes. After adjustment for age and sex, the risk of long-term mortality increased as eRVSP increased (adjusted HR (aHR) 1.20, 95% CI 1.06 to 1.36 in borderline PHT, to aHR 3.32, 95% CI 2.85 to 3.86 in severe PHT, p<0.0001). There was a mortality threshold seen from mild PHT onwards (eRVSP 41.36–44.15 mm Hg; aHR 1.41, 95%CI 1.17 to 1.68). Conclusions In this large cohort study, we characterise the relationship between AR and PHT in adults. In patients with ≥moderate AR, PHT is associated with a progressive risk of mortality, even at mildly elevated levels.