Optimal Tricuspid Regurgitation Velocity to Screen for Pulmonary Hypertension in Tertiary Referral Centers

Background: A mean pulmonary artery pressure >20 mm Hg now defines pulmonary hypertension. We hypothesize that echocardiographic thresholds must be adjusted.

Research question: Should tricuspid regurgitation velocity thresholds to screen for pulmonary hypertension be revised, given the new hemodynamic definition?

Study design and methods: This multicenter retrospective study included 1,608 patients who underwent both echocardiography and right heart catherization within 4 weeks. The discovery cohort consisted of 1,081 individuals; the validation cohort included 527. Screening criteria for pulmonary hypertension were derived with the use of receiver operating characteristic analysis and the Youden index, assuming equal cost for false-positive and -negative classification. A lower threshold was calculated with the use of a predefined sensitivity: 95%.

Results: In the discovery cohort, echocardiographic tricuspid regurgitation velocity had a good discrimination for pulmonary hypertension: area under the curve, 88.4 (95% CI, 85.3-91.5). A 3.4-m/s threshold provided a 78% sensitivity, 87% specificity, and 6.13 positive likelihood ratio to detect pulmonary hypertension; 2.7 m/s had a 95% sensitivity and 0.12 negative likelihood ratio to exclude pulmonary hypertension. In the validation cohort, the discovery threshold of 2.7 m/s provided sensitivity and negative likelihood ratios of 80% and 0.31, respectively. Right cardiac size improved detection of pulmonary hypertension in the lower tricuspid regurgitation velocity groups.

Interpretation: Our data support a lower tricuspid regurgitation velocity of approximately 2.7 m/s for screening pulmonary hypertension, with a high sensitivity in tertiary referral centers. Right heart chamber measurements improve the diagnostic yield of echocardiography.