Related Experiment Video
Updated: Jan 24, 2026

Increasing Pulmonary Artery Pulsatile Flow Improves Hypoxic Pulmonary Hypertension in Piglets
Published on: May 11, 2015
Threshold of Pulmonary Hypertension Associated With Increased Mortality
Geoff Strange1, Simon Stewart2, David S Celermajer3
1University of Notre Dame, Fremantle, Western Australia, Australia.
Background:
There is increasing evidence that current thresholds for diagnosing pulmonary hypertension (PHT) underestimate the prognostic impact of PHT.
Objectives:
The aim of this study was to determine the prognostic impact of increasing pulmonary pressures within the National Echocardiography Database of Australia cohort (n = 313,492).
Methods:
The distribution of estimated right ventricular systolic pressure (eRVSP) was examined in 157,842 men and women. All had data linkage to long-term survival during median follow-up of 4.2 years (interquartile range: 2.2 to 7.5 years).
Results:
The cohort comprised 74,405 men and 83,437 women 65.6 ± 17.7 years of age. Overall, 17,955 (11.4%), 7,016 (4.4%), and 4,515 (2.9%) subjects had eRVSP levels indicative of mild (40 to 49 mm Hg), moderate (50 to 59 mm Hg), or severe (≥60 mm Hg) PHT, respectively, assuming a right atrial pressure of 5 mm Hg. These subjects were more likely to die during long-term follow up (for severe PHT, adjusted hazard ratio: 9.73; 95% confidence interval: 8.60 to 11.0; p < 0.001). After adjustment for age, sex, and evidence of left heart disease, those subjects with eRVSP levels within the third (28.05 to 32.0 mm Hg; hazard ratio: 1.410; 95% confidence interval: 1.310 to 1.517) and fourth (32.05 to 38.83 mm Hg; hazard ratio: 1.979; 95% confidence interval: 1.853 to 2.114) quintiles had significantly higher mortality (p < 0.001) than those in the lowest quintile. Accordingly, a clear and consistent threshold of increased mortality (including 1- and 5-year actuarial mortality) around an eRVSP of 30.0 mm Hg was evident.
Conclusions:
In this large and unique cohort, the prognostic impact of clinically accepted levels of PHT was confirmed. Moreover, a distinctly lower threshold for increased risk for mortality (eRVSP >30.0 mm Hg) indicative of PHT was identified. (A Longitudinal Cohort Study of Echocardiograms From Public and Private Echocardiography Laboratories From Around Australia, Linked With the National Deaths Index; ACTRN12617001387314).
Related Concept Videos
Pulmonary Hypertension: Classification and Pathogenesis
There are various classifications for PH, each relating to different underlying causes and also...
Treatment for Pulmonary Arterial Hypertension: Phosphodiesterase Inhibitors
Among the PDE5 inhibitors, sildenafil (Revatio) stands out as a competitive and selective inhibitor. It operates by elevating cellular levels of cGMP and augmenting signaling through the cGMP-PKG pathway, promoting vasodilation. Upon oral...
Treatment for Pulmonary Arterial Hypertension: Endothelin Receptor Antagonists
ETs are synthesized through a complex sequence of enzymatic steps, primarily involving an enzyme referred to as endothelin-converting enzyme...
Treatment for Pulmonary Arterial Hypertension: Prostacyclin Receptor Agonists
These agonists bind to the IPR receptor situated on the plasma membrane of the pulmonary artery smooth muscle cells. This binding triggers a cascade of reactions known as the GS-AC-cAMP-PKA pathway. This pathway results in the relaxation of smooth muscle...
Treatment for Pulmonary Arterial Hypertension: Oxygen Therapy for Respiratory Failure
Oxygen therapy is vital in increasing and maintaining blood oxygen levels in PAH patients. As a result, it aids in reducing fatigue,...
Treatment for Pulmonary Arterial Hypertension: Receptor Tyrosine Kinase Inhibitors and Calcium Channel Blockers
TKIs, such as imatinib (Gleevec), are particularly effective in tackling the growth and mitogenic factors that become upregulated in PAH patients. These factors contribute to the...

