Three-dimensional right ventricular ejection fraction: a strong predictor of outcomes in patients undergoing cardiac surgery, a multicenter study.
Authors: Posada-Martinez E L , Ivey-Miranda J B , Ortiz-Leon X A , Arias-Godinez J A , Fritche-Salazar J F , Rodriguez-Zanella H G , Ruiz Esparza M E , Romero-Zertuche D , Silvestre-Flores I I , Morales-Portano J , Mcnamara R L , Sugeng L 
Published: January 2025

Abstract

Background
Cardiac surgery is the cornerstone of treatment of several heart conditions.1 Risk stratification before surgery is crucial to patient’ prognostic, but commonly used scores do not include right ventricular (RV) function.2

Purpose
To evaluate if 3D RV ejection fraction (RVEF) is independently associated with in-hospital outcomes in patients undergoing cardiac surgery after adjusting for the EuroSCORE.

Methods
Prospective multicenter (3 centers in 2 countries) cohort study of adult patients undergoing cardiac surgery. A comprehensive transesophageal echocardiogram was performed in the operating room before the surgery to capture dedicated acquisitions of the RV. The images were analyzed offline in TOMTEC imaging system. The primary outcome was a composite of in-hospital mortality or need of temporary ventricular assistance device after surgery. Exploratory endpoints were time on mechanical ventilation and time on inotropes after the surgery. Univariate and multivariable Cox regression model was used to analyze the association of RVEF with the primary outcome after adjusting for the EuroSCORE.

Results
We included 248 patients. The median age was 60 y/o and 43% were female. Aortic valve repair or replacement and CABG were the most common procedures. Sixty nine percent had normal RVEF (RVEF ≥45%) and 31% low RVEF (RVEF &lt;45%). Baseline demographic characteristics were similar between groups except for atrial fibrillation, which was more common in the low RVEF group. Left ventricular ejection fraction was lower in patients with low RVEF (50 ± 14 vs. 54 ± 12, p=0.041). The volume of the atria and the RV size were higher in patients with low RVEF (p&lt;0.04 for all). RV function parameters (TAPSE, FAC and RVFWLS) were lower in the group of low RVEF (p&lt;0.001 for all). The group with low RVEF showed higher PASP (42 ± 19 vs. 53 ± 27 mmHg, p=0.003) and lower RV–pulmonary artery coupling [0.54 (IQR 0.33 – 0.78 mm/mmHg) vs. 0.34 (IQR 0.24 – 0.53 mm/mmHg), p&lt;0.001]. The primary outcome occurred in 28 patients (11%). Table 1 illustrates the univariate and multivariable association of RVEF as a continuous variable as well as other parameters with the primary outcome. When analyzing groups of low vs high RVEF (binary variable), patients with low RVEF showed higher risk of the primary outcome [HR 2.46 (95% CI 1.10, 5.50), p=0.028]. At 30 days, the survival free of the primary endpoint was 72±8% vs. 93±3% (p&lt;0.001) in low vs normal RVEF, respectively (Figure 2, panel A). Further, RVEF was associated with shorter time on mechanical ventilation (r= -0.27, p&lt;0.001) and shorter time on inotropes (r= -0.20, p=0.01); (Figure 2, panel B and C).

Conclusion
Three-dimensional RVEF is a strong predictor of outcomes in patients undergoing cardiac surgery. This multicenter study suggests that including RV function in the evaluation of patients undergoing surgery might improve stratification.
Table 1.
Figure 1.