Impact of Ejection Fraction and Aortic Valve Gradient on Outcomes of Transcatheter Aortic Valve Replacement

Abstract

Background: In patients with aortic stenosis undergoing transcatheter aortic valve replacement (TAVR), studies have suggested that reduced left ventricular (LV) ejection fraction (LVEF) and low aortic valve gradient (AVG) are associated with worse long-term outcomes. Because these conditions commonly coexist, the extent to which they are independently associated with outcomes after TAVR is unknown.

Objectives: The purpose of this study was to evaluate the impact of LVEF and AVG on clinical outcomes after TAVR and to determine whether the effect of AVG on outcomes is modified by LVEF.

Methods: Using data from 11,292 patients who underwent TAVR as part of the Transcatheter Valve Therapies Registry, we examined rates of 1-year mortality and recurrent heart failure in patients with varying levels of LV dysfunction (LVEF <30% vs. 30% to 50% vs. >50%) and AVG (<40 mm Hg vs. ≥40 mm Hg). Multivariable models were used to estimate the independent effect of AVG and LVEF on outcomes.

Results: During the first year of follow-up after TAVR, patients with LV dysfunction and low AVG had higher rates of death and recurrent heart failure. After adjustment for other clinical factors, only low AVG was associated with higher mortality (hazard ratio: 1.21; 95% confidence interval: 1.11 to 1.32; p < 0.001) and higher rates of heart failure (hazard ratio: 1.52; 95% confidence interval: 1.36 to 1.69; p <0.001), whereas the effect of LVEF was no longer significant. There was no evidence of effect modification between AVG and LVEF with respect to either endpoint.

Conclusions: In this series of real-world patients undergoing TAVR, low AVG, but not LV dysfunction, was associated with higher rates of mortality and recurrent heart failure. Although these findings suggest that AVG should be considered when evaluating the risks and benefits of TAVR for individual patients, neither severe LV dysfunction nor low AVG alone or in combination provide sufficient prognostic discrimination to preclude treatment with TAVR.

Keywords: AV gradient; LVEF; TAVR; left ventricular dysfunction; stroke; surgical aortic valve replacement.

Figure 1. Study Flow Chart

Flow chart depicting derivation of the study population from the TVT Registry

Figure 2. Cumulative Incidence of Outcomes over Time Stratified by Left Ventricular Ejection Fraction

Kaplan-Meier curves depicting all-cause mortality (panel A) and recurrent heart failure hospitalization (panel B) over the first year of follow-up after TAVR, stratified by LVEF.

Figure 2. Cumulative Incidence of Outcomes over Time Stratified by Left Ventricular Ejection Fraction

Kaplan-Meier curves depicting all-cause mortality (panel A) and recurrent heart failure hospitalization (panel B) over the first year of follow-up after TAVR, stratified by LVEF.

Figure 3. Cumulative Incidence of Outcomes over Time Stratified by Mean Aortic Valve Gradient

Kaplan-Meier curves depicting all-cause mortality (panel A) and recurrent heart failure hospitalization (panel B) over the first year of follow-up after TAVR, stratified by mean AVG.

Figure 3. Cumulative Incidence of Outcomes over Time Stratified by Mean Aortic Valve Gradient

Kaplan-Meier curves depicting all-cause mortality (panel A) and recurrent heart failure hospitalization (panel B) over the first year of follow-up after TAVR, stratified by mean AVG.

Figure 4. One-Year Clinical Outcomes Stratified by AV gradient and LVEF

1-year Kaplan-Meier estimates of all-cause mortality (panel A) and recurrent heart failure hospitalization (panel B) after TAVR, stratified by LVEF and AVG.

Figure 5. (Central Illustration): Adjusted Association between Baseline LVEF and AVG and 1-year outcomes after TAVR

Forest plot demonstrating the association of baseline LVEF and AVG with all-cause mortality and recurrent heart failure after adjustment for potential confounders.