Pressure-strain-volume analysis-derived wasted work predicts clinical outcomes after transcatheter tricuspid valve intervention
Authors: Bartkowiak J , Dernektsi C , Fabian A , Szijarto A , Angellotti D , George I , Kodali S , Windecker S , Brugger N , Kovacs A , Praz F , Hahn R T 
Published: January 2025

Abstract

Background
The pressure-strain loop is a non-invasive alternative to the traditional pressure-volume analysis for calculating myocardial work. Incorporating volume into work calculations may be particularly beneficial in evaluating patients with tricuspid regurgitation (TR) undergoing transcatheter tricuspid valve intervention (TTVI), who often present with highly varied load conditions.

Purpose
The study aimed to test the hypothesis that pressure-strain-volume analysis-derived right ventricular (RV) work will predict the composite clinical outcome of heart failure hospitalization (HFH) and death within 12 months after the TTVI.

Methods
Patients undergoing TTVI at two tertiary centers were included between June 2021 and November 2023. The pre-procedural three-dimensional echocardiographic acquisitions of the RV (to obtain RV volumes and global longitudinal strain) and RV pressures obtained from same day, pre-procedural right heart catheterization or calculated from TR maximal velocity and right atrial pressure were integrated into pressure-strain-volume loops using dedicated software (ReVISION, Argus Cognitive, USA). The pressure-strain-volume derived myocardial work was quantified as the volume under the three-dimensional curve and characterized by the following metrics: global work index (GWIV), global constructive work (GCWV), global wasted work (GWWV), and global work efficiency (GWEV). Conventional pressure-strain analysis-derived metrics were also calculated as previously described (1). The composite outcome was HFH or death within 12 months after TTVI. Cox regression analysis was performed to investigate the possible associations with the composite outcome and included all baseline clinical, echocardiographic, hemodynamic and RV work parameters. Variables were considered for multivariate analysis when they were related to composite endpoint on univariate analysis with a p value &lt;0.05.

Results
Of 76 patients included, 52.6% were female. The mean age was 79.3 ± 7.5 years and median TRI-Score 5 [4-7] points. Transcatheter interventions included transcatheter tricuspid valve repair (61.8%) and tricuspid valve replacement (38.2%). TR at discharge was trace/mild, moderate, severe or massive in 60.6%, 26.3%, 13.2% and 0% cases respectively. At 12-month follow-up, 26 (34.2%) patients met the composite endpoint. After adjustment for number of HFH 12 months prior to TTVI, atrial fibrillation, glomerular filtration rate and NT-proBNP, GWWV remained the only baseline parameter significantly associated with increased risk of HFH and death at 12-month follow-up in the multivariate analysis with an adjusted OR of 1.079 (95% confidence interval 1.020 - 1.143; p = 0.009).

Conclusion
Results of this analysis show that baseline pressure-strain-volume analysis-derived wasted work identifies patients at higher risk for HFH or death following TTVI. Thus, the GWWV calculation may help identify individuals who are more likely to benefit from TTVI.