Prevalence and prognostic significance of pulmonary hypertension in adults with left ventricular diastolic dysfunction

Aims Pulmonary hypertension (PHT) appears to be very common in heart failure with preserved ejection fraction but details on its prevalence, severity and prognostic implications have not been well defined. We, therefore, aimed to document PHT and its impact on mortality among adults with left ventricular (LV) diastolic dysfunction (LVDD). Methods We analysed the profile and outcomes of 16 058 adults with LVDD (and with preserved LV ejection fraction, >50%) from the National Echocardiography Database of Australia. Subjects were classified according to their peak tricuspid regurgitation velocity (TRV), reflecting PHT risk, and we then evaluated the relationship between conventional thresholds of increasing risk of PHT and subsequent mortality, during median follow-up of 3.1 (IQR 1.6-5.2) years. Results Mean age was 73 +/- 12 years and 9216 (57.4%) were female. Overall, 2611 (16.3%) had normal TRV levels (<2.5 m/s) indicative of no PHT, compared with 3471 (21.6%), 8450 (52.6%) and 1526 (9.5%) with TRV levels indicative of borderline (2.5-2.8 m/s), intermediate (2.9-3.4 m/s) and high-risk for PHT (>3.4 m/s). The 1-year and 5-year actuarial mortality (1701/1546 and 4232/8445 deaths, respectively) increased from 6.5% and 34.0% to 27.7% and 78.5%, respectively (p<0.0001), from normal to severely elevated TRV. Adjusted risk (HR) of mortality increased 1.28-fold (95% CI 1.15 to 1.41), 1.51-fold (95% CI 1.38 to 1.65) and 3.47-fold (95% CI 3.13 to 3.85) in those with borderline, intermediate and high risk of PHT versus normal TRV. This observation persisted when excluding atrial fibrillation cases, and when male and female cohorts were assessed separately. Mortality rates increased perceptibly at the second decile distribution of TRV (2.37-2.55 m/s) with a marked increase in mortality from the fifth decile (2.91-3.00 m/s) upwards. Conclusion We demonstrate the negative prognostic impact of elevated TRV levels in many adults with isolated LVDD. A threshold of increased mortality was observed at TRV levels equivalent to 'borderline risk' of PHT.