Impact of right ventricular - pulmonary arterial coupling on mortality after transcatheter aortic valve implantation in patients with aortic stenosis
Authors: Piris Sanchez A , Salido Tahoces L , Pardo Sanz A , Gonzalez Martin S , Mestre Barcelo J L , Dominguez-Rodriguez L M , Tirado-Conte G , Hernandez Sanchez E , Fernandez-Golfin Loban C , Garcia Martin A , Gonzalez Gomez A , Monteagudo Ruiz J M , Hinojar Baydes R , Zamorano Gomez J L , Sanchez Recalde A 
Published: October 2024

Abstract

Background
Aortic stenosis (AS) leads to left ventricle (LV) pressure overload. In more advanced stages of the disease, this pressure, which is transmitted through the pulmonary vasculature, may result in right ventricle (RV) remodeling and eventual dilatation and disfunction. RV failure is associated with impair prognosis, even after relief of the obstruction. The interplay of pulmonary arterial (PA) pressure and RV function can be assess using RV-PA coupling index; in a compensate state RV function is coupled with pulmonary pressure, and this function has a proper response to an increase in pulmonary afterload; in contrast, when RV function uncouples with pulmonary pressure it means that RV function can no longer sustain PA afterload, leading to a decompensate state. RV-PA uncoupling has already been associated with poor prognosis in other heart conditions, such as heart failure or pulmonary hypertension; however, there is still not much evidence on how RV-PA uncoupling prior transcatheter aortic valve implantation (TAVI) impacts on mortality.

Purpose
Assess the impact of RV-PA uncoupling on all-cause mortality after TAVI in patients with aortic stenosis.

Methods
In a prospective TAVI registry, patients were included if they had an adequate echocardiographic evaluation prior TAVI. All-cause mortality after the procedure was analyzed in two subgroups, according to their RV-PA coupling status. RV-PA was assess using tricuspid annular plane systolic excursion (TAPSE) and pulmonary arterial systolic pressure (PASP). The cut-off value was 0.39, consistent with other studies. Hazard ratios (HR) are calculated by univariate and multivariate Cox proportional hazard model. Multivariate adjustment included baseline characteristics – including age, gender, hypertension, diabetes, dyslipidemia, atrial fibrillation, and serum albumin –, and Society of Thoracic Surgeons Predicted Risk of Mortality (STS-PROM) and European System for Cardiac Operative Risk Evaluation (EUROSCORE) II.

Results
A total of 1190 patients underwent TAVI from January 2011 to December 2023; 315 patients were eligible, with mean age 82,24 years (± 8,0), 52% being women, and a mean EUROSCORE II score of 4.0 (± 9,3). The RV-PA cut-off value of 0.39 stratified patients into groups of RV-PA coupling (n = 194/63,6 %) or uncoupling (n = 121/38,4 %). During follow-up time (35,94 months ±25,6), patients with unpaired coupling had a 64% more risk of all-cause mortality in univariate analysis and, after adjusting for the parameters above, a 58% increased risk in multivariate analysis. Table.

Conclusions
Patients with significant aortic stenosis who had an impair RV-PA coupling prior TAVI had a significant increased risk of all-cause mortality. This suggests the need to incorporate this parameter to our right-side hemodynamics evaluation prior the procedure. Broader experience to determine its application and cut-off value are still needed.