Prognostic value of the right ventricular ejection fraction using three-dimensional echocardiography: Systematic review and meta-analysis

AIMS

Three-dimensional echocardiography (3DE) is a robust method for measuring the right ventricular (RV) ejection fraction (EF), which is closely associated with outcomes. We performed a systematic review and meta-analysis (1) to examine the prognostic value of RVEF and (2) to compare its prognostic value with that of left ventricular (LV) EF and LV global longitudinal strain (GLS). We also performed individual patient data analysis to validate the results.

METHODS AND RESULTS

We searched articles reporting the prognostic value of RVEF. Hazard ratios (HR) were re-scaled using the within-study standard deviation (SD). To compare predictive values of RVEF and LVEF or LVGLS, the ratio of HR related to a 1-SD reduction of RVEF versus LVEF or LVGLS was calculated. Pooled HR of RVEF and pooled ratio of HR were analyzed in a random-effects model. Fifteen articles with 3,228 subjects were included. Pooled HR of a 1-SD reduction of RVEF was 2.54 (95% confidence interval (CI): 2.15-3.00). In subgroup analysis, RVEF was significantly associated with outcome in pulmonary arterial hypertension (PAH) (HR: 2.79, 95% CI: 2.04-3.82) and cardiovascular (CV) diseases (HR: 2.23, 95%CI: 1.76-2.83). In studies reporting HRs for both RVEF and LVEF or RVEF and LVGLS in the same cohort, RVEF had 1.8-fold greater prognostic power per 1-SD reduction than LVEF (ratio of HR: 1.81, 95%CI: 1.20-2.71), but had predictive value similar to that of LVGLS (ratio of HR: 1.10, 95%CI: 0.91-1.31) and to LVEF in patients with reduced LVEF (ratio of HR: 1.34, 95%CI: 0.94-1.91). In individual patient data analysis (n = 1,142), RVEF < 45% was significantly associated with worse CV outcome (HR: 4.95, 95% CI: 3.66-6.70), even in patients with reduced or preserved LVEF.

CONCLUSIONS

The findings of this meta-analysis highlight and support the use of RVEF assessed by 3DE to predict CV outcomes in routine clinical practice in patients with CV diseases and in those with PAH.

Association of Right Ventricular Functional Parameters With Adverse Cardiopulmonary Outcomes: A Meta-analysis

AIMS

We aimed to confirm that three-dimensional echocardiography-derived right ventricular ejection fraction (RVEF) is better associated with adverse cardiopulmonary outcomes than the conventional echocardiographic parameters.

METHODS

We performed a meta-analysis of studies reporting the impact of unit change of RVEF, tricuspid annular plane systolic excursion (TAPSE), fractional area change (FAC), and free-wall longitudinal strain (FWLS) on clinical outcomes (all-cause mortality and/or adverse cardiopulmonary outcomes). Hazard ratios (HRs) were rescaled by the within-study SDs to represent standardized changes. Within each study, we calculated the ratio of HRs related to a 1 SD reduction in RVEF versus TAPSE, or FAC, or FWLS, to quantify the association of RVEF with adverse outcomes relative to the other metrics. These ratios of HRs were pooled using random-effects models.

RESULTS

Ten independent studies were identified as suitable, including data on 1,928 patients with various cardiopulmonary conditions. Overall, a 1 SD reduction in RVEF was robustly associated with adverse outcomes (HR = 2.64 [95% CI, 2.18-3.20], P < .001; heterogeneity: I² = 65%, P = .002). In studies reporting HRs for RVEF and TAPSE, or RVEF and FAC, or RVEF and FWLS in the same cohort, head-to-head comparison revealed that RVEF showed significantly stronger association with adverse outcomes per SD reduction versus the other 3 parameters (vs TAPSE, HR = 1.54 [95% CI, 1.04-2.28], P = .031; vs FAC, HR = 1.45 [95% CI, 1.15-1.81], P = .001; vs FWLS, HR = 1.44 [95% CI, 1.07-1.95], P = .018).

CONCLUSION

Reduction in three-dimensional echocardiography-derived RVEF shows stronger association with adverse clinical outcomes than conventional right ventricular functional indices; therefore, it might further refine the risk stratification of patients with cardiopulmonary diseases.