Comprehensive echocardiographic evaluation in CTEPH: the impact of TAPSE/sPAP and RVOT acceleration time on the diagnostic performance of peak tricuspid regurgitation velocity
Authors: Lacerda Teixeira B , Grazina A , Jacinto S , Teixeira R , Cardoso I , Viegas J , Reis J , Galrinho A , Almeida Morais L , Cacela D , Ramos R , Fiarresga A , Cruz Ferreira R 
Published: November 2023

Abstract

Introduction
The hemodynamic definition of pulmonary hypertension (PH) has been updated, with lowering of the mean pulmonary arterial pressure (mPAP) threshold from 25 to 20 mmHg according to the new 2022 ESC/ERS Guidelines. Peak tricuspid regurgitation velocity (PTRV) remains the key variable for assigning the echocardiographic probability of PH, but a comprehensive echocardiographic evaluation also includes detecting additional signs suggestive of PH. Since the cut-off for PTRV remained the same (&gt;2.8m/s), the potential impact of other echocardiographic variables in the diagnosis of PH according to the new criteria has not been extensively evaluated.

Objectives
To evaluate the screening power of the standard echocardiographic parameters to detect PH according to the new guidelines and to establish the sensitivity and specificity of adding tricuspid annular plane systolic excursion/systolic pulmonary arterial pressure ratio (TAPSE/sPAP) and right ventricular outflow tract acceleration time (RVOT AT) to PTRV in the diagnosis of PH.

Methods
Prospective registry of consecutive intermediate-high- and high-risk PE pts submitted to CDT in a single tertiary center. 3 months after the procedure, patients were submitted to a right heart catheterization and echocardiogram to screen chronic thromboembolic pulmonary hypertension (CTEPH). According to new PH criteria, patients were divided in two groups, and echocardiographic parameters were analyzed. ROC curve was performed to evaluate the sensitivity and specificity of each variable.

Results
17 pts (60% women, mean age 59 ± 16 years) were included. Among these, 7 pts (41,2%) were diagnosed with pre-capillary PH by RHC at 3 months of follow-up. Among echocardiographic parameters, PTRV (p 0.015), presence of tricuspid regurgitation (0.034) and TAPSE/sPAP (p 0.041) were significantly different between groups. Other parameters did not show significant differences (Fig 1). Regarding PTRV, the cut-off of 2.8 m/s achieved a low sensitivity of 28.6%, although 100% of specificity (AUC 0.643) for the diagnosis of PH. Adding TAPSE/sPAP &lt; 0,55 mm/mmHg (recommended cut-off) to the screening, increased the sensitivity to 42,9% without losing specificity (AUC 0,714). When adding RVOT AT &lt; 105 ms (recommended cut-off) to the analysis, meaning, using three echocardiographic variables combined, it achieved a sensitivity of 85,7%, although the specificity was lower – 80% (AUC 0,829) (Fig 2).

Conclusion
PTRV and TAPSE/sPAP ratio are the only conventional echocardiographic parameters to be significantly different when comparing patients with and without PH. However, with the recent update in PH criteria, the use of the PTRV recommended cut-off leads to a significant underdiagnosis in our population. Although PTRV did not seem to predict accurately the presence of PH when used alone, when combined with TAPSE/sPAP and RVOT AT, our data suggests a growth in the screening power, without a major loss in specificity.Figure 1Figure 2