Assessment of the gradient gap after TAVR with balloon and self-expandable valves: Analysis of a large patient cohort.

BACKGROUND

Transcatheter aortic valve replacement (TAVR) is a key treatment for severe aortic stenosis (AS). Several studies have consistently shown discrepancies between transvalvular gradients measured by transthoracic echocardiography (TTE) and those obtained invasively. The aim of this study was to evaluate this discrepancy in a large patient cohort and determine whether it is associated with clinical outcomes.

METHODS

This study included patients with severe AS who underwent TAVR using either balloon-expandable (BEVs) or self-expanding valves (SEVs). The primary endpoint was the magnitude of discrepancy between peak transvalvular gradients measured by TTE and invasive hemodynamic assessment. Secondary endpoints included the association of this gradient difference with in-hospital, 30-day, and 1-year mortality. In addition, multivariable linear regression analysis was performed to identify independent predictors of gradient discrepancy.

RESULTS

A total of 1,798 TAVR patients were included: 799 received BEVs and 999 received SEVs. Postprocedural mean peak gradients by echocardiography were significantly higher in the BEV group (20 ± 8 mmHg) than in the SEV group (15 ± 7 mmHg; P < .001). Invasive mean peak gradients were lower overall, at 5.9 ± 4 mmHg for BEVs and 5.3 ± 3.8 mmHg for SEVs (P = .001). The mean difference between echocardiographic and invasive measurements was significantly greater in the BEV group (14 ± 8 mmHg) compared to the SEV group (10 ± 7 mmHg; P < .001). There were no statistically significant differences in mortality between the BEV and SEV groups. Additionally, female sex, hypertension, preserved left ventricular function, small valve size, and small aortic annulus were all linked to greater differences between echocardiographic and invasive gradients.

CONCLUSION

echocardiographic gradients after TAVR consistently overestimate invasive values, especially with balloon-expandable valves, but without impacting short or mid-term mortality.