Improving the echocardiographic assessment of pulmonary pressure using the tricuspid regurgitant signal-The chin vs the beard

Aim: Transthoracic echocardiography (TTE) is a fundamental investigation for the noninvasive assessment of pulmonary hemodynamics and right heart function. The aim of this study was to assess the correlation and agreement of Doppler calculation of right ventricular systolic pressure (RVSP) and pulmonary vascular resistance (PVR) using chin and beard measurements of tricuspid regurgitant velocity (TRVmax), with invasive pulmonary artery systolic pressure (PASP) and PVR. Methods: One hundred patients undergoing right heart catheterisation (RHC) and near simultaneous transthoracic echocardiography were studied. TRVmax was recorded for chin measurement (distinct peak TRVmax signal) and where available (63 patients), beard measurement (higher indistinct peak TRVmax signal). Results: Measurable TRV signal was obtained in 96 patients. Mean RVSPchin 54.7 +/- 22.7 mm Hg and RVSPbeard 68.6 = 23 +/- 26.3 mm Hg (P < .001). There was strong correlation between both RVSP chin and RVSPbeard with invasive PASP (Pearson's r = .9, R-2 = 0.82, P < .001 - r = .88, R = .78, P < .001, respectively.). Bland-Altman analysis for RVSPchin and RVSPbeard showed a mean bias of -0.5 mm Hg (95% limits of agreement -21.4 to 20.5 mm Hg) and -10.7 (95% LOA -35.5 to 14.2 mm Hg), respectively. Receiver operator characteristics of TRVmax chin and beard for diagnosis of pulmonary hypertension was assessed with optimal cut-offs being 2.8 m/s (sensitivity 93%, specificity 87%) and 3.2 m/s (sensitivity 91%, specificity 82%), respectively. There was similar correlation between PVRchin and PVRbeard (r = .87, R-2 = 0.75, P < .001 and r = .86, R-2 = 0.74, P < .001, respectively). At higher PVR, there was overestimation of calculated PVR using PVRbeard. Conclusion: The accuracy of noninvasive measurement of right heart pressures is increased using the chin in estimation of both RVSP and PVR.