A distinctly lower threshold of pulmonary hypertension (PH) was linked to an increased risk for mortality, according to a study published in the Journal of the American College of Cardiology.
Utilizing the National Echo Database Australia, investigators evaluated individual echocardiographic measurement and report data as of October 2017. Patients with peak tricuspid regurgitation velocity (TRV)/estimated right ventricular systolic pressure (eRVSP) from their last recorded echocardiographic examinations were included (n=157,842).
Investigators categorized eRVSP by current clinical guidelines: normal (eRVSP <40 mm Hg), mildly elevated (eRVSP 40-49.9 mm Hg), moderately elevated (eRVSP 50.-59.9 mm Hg), and severely elevated (eRVSP ≥60 mm Hg). Fatal events were identified during a median follow-up of 4.2 years for all patients.
Patients with eRVSP levels indicative of mild (n=17,955 [11.4%]), moderate (n=7016 [4.4%]), and severe (n=4515 [2.9%]) PH were more likely to die during long-term follow-up. Adjusting for age and sex, patients with severely elevated eRVSP were almost 10-fold more likely to die within 5 years (adjusted hazard ratio, 9.73; 95% CI, 8.6-11; P <.001).
Patients without eRVSPs were less likely to die in long-term follow-up (adjusted hazard ratio, 0.861; 95% CI, 0.847-0.876). Post hoc analyses confirmed a clear and consistent threshold of an eRVSP of 30 mm Hg persisted when examining cardiovascular- and respiratory-related mortality (including 1- and 5-year actuarial mortality).
Limitations of this study include incomplete data from echocardiography that do not capture other important clinical details that are pivotal to health outcomes.
The researchers confirmed that current recommendations that patients should be carefully clinically evaluated for symptoms that may be consistent with PH, and symptomatic patients should undergo echocardiography. Patients with either low (TRV <2.8 m/s) or high (TRV >3.4 m/s) TRV levels should be considered at risk for PH and/or a poorer prognostic outcome. Further investigation should be taken to unmask any underlying disease that may be more proactively managed than suggested by current expert guidelines. There is still an area of uncertainty around the clinical management of patients currently classified at intermediate risk for PH (TRV 2.9 to 3.4 m/s, correlating to a range of eRVSP of 33 to 46 mm Hg).
Disclosure: The National Echo Database Australia was initially supported (database engineering and infrastructure costs) through unrestricted research grants from Actelion, Bayer, and GlaxoSmithKline. David S. Celermajer, MD, PhD, works at an institution that has received clinical trials funding and educational grants from Actelion. David Prior, MBBS, PhD, has received payments for talks from Actelion.
Strange G, Stewart S, Celermajer DS, et al; NEDA Contributing Sites. Threshold of pulmonary hypertension associated with increased mortality. J Am Coll Cardiol. 2019; 73(21):2660-2672.