Background: Transthoracic echocardiography (TTE) is used to estimate pulmonary artery systolic pressure, but an adequate tricuspid regurgitation velocity (TRV) needed to calculate pulmonary artery systolic pressure is not always present. It is unknown whether the absence of a measurable TRV signifies normal pulmonary artery pressure.
Methods and results: We extracted hemodynamic, TTE, and clinical data from Vanderbilt's deidentified electronic medical record in all patients referred for right heart catheterization between 1998 and 2014. Pulmonary hypertension (PH) was defined as mean pulmonary artery pressure ≥25 mm Hg. We examined the prevalence and clinical correlates of PH in patients without a reported TRV. We identified 1262 patients with a TTE within 2 days of right heart catheterization. In total, 803/1262 (64%) had a reported TRV, whereas 459 (36%) had no reported TRV. Invasively confirmed PH was present in 47% of patients without a reported TRV versus 68% in those with a reported TRV (P<0.001). Absence of a TRV yielded a negative predictive value for excluding PH of 53%. Right ventricular dysfunction, left atrial dimension, elevated body mass index, higher brain natriuretic peptide, diabetes mellitus, and heart failure were independently associated with PH among patients without a reported TRV.
Conclusions: PH is present in almost half of patients without a measurable TRV who are referred for both TTE and right heart catheterization. Clinical and echocardiographic features of left heart disease are associated with invasively confirmed PH in subjects without a reported TRV. Clinicians should use caution when making assumptions about PH status in the absence of a measurable TRV on TTE.
Keywords: echocardiography; hemodynamics; imaging; pulmonary hypertension; right heart catheterization.
© 2018 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.