Measuring Post-TAVI Gradients and Their Implications: Are Invasive and Echocardiographic Assessments Comparable?

Transcatheter aortic valve implantation (TAVI) is considered the treatment of choice for a significant proportion of patients with symptomatic aortic stenosis. Outcomes have improved markedly thanks to advancements in device technology and meticulous pre-procedural planning.

Following valve implantation, proper hemodynamic assessment is essential. However, the agreement and prognostic value of pressure gradients obtained invasively versus those measured via echocardiography remain controversial.

A research group led by van den Dorpel, at the Thoraxcenter in Rotterdam, conducted a study aimed to assess the predictive value of transvalvular gradients measured invasively and echocardiographically after TAVI, while comparing differences between self-expanding valves (SEV) and balloon-expandable valves (BEV).

Researchers conducted a retrospective analysis with propensity score matching (436 SEV vs. BEV pairs). Gradients were measured invasively before and immediately after TAVI, while echocardiographically-measured gradients were assessed before, within 24 hours, and one year after the procedure.

The mean age for the cohort was 80 years, with a mean STS score of 3.41. Before implantation, echocardiographic assessments rendered higher gradients compared to invasive measurements, regardless of the type of valve used (39.0 mmHg vs. 36.0 mmHg; p<0.001).

After TAVI, invasively-measured gradients were similar for BEV and SEV (3.0 [0.0–6.0] mmHg vs. 3.0 [0.0–6.0] mmHg; p=0.166). However, non-invasive assessments revealed higher gradients, with a more pronounced difference in BEVs compared to SEVs (7.0 [4.0–11.0] mmHg for BEV and 5.0 [2.0–7.0] mmHg for SEV; p<0.001).

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Patients who received smaller devices showed greater discrepancies, particularly with balloon-expandable valves (11.0 mmHg discrepancy for 20-mm SAPIEN 3 vs. 7.0 mmHg for 29-mm SAPIEN 3; p=0.001). In the subgroup with small annuli (<430 mm²), the discrepancy was even more marked for BEVs.

Invasively-measured post-TAVI gradients independently predicted all-cause mortality at 30 days, 1 year, and 2 years (hazard ratio [HR]: 1.07, 1.06, and 1.05 respectively; p<0.05), while echocardiographic gradient measurements did not show the same association (p=0.248; p=0.639; and p=0.979, respectively).

A residual gradient >10 mmHg was associated with increased all-cause mortality.

Conclusion

This study found that invasively-measured post-TAVI gradients were correlated with both short- and long-term mortality. In this patient cohort, echocardiography consistently overestimated gradients, especially following balloon-expandable valve implantation. These findings underscore the clinical importance of standardized invasive measurements after TAVI for proper prognostic stratification.

Original Title: Prognostic value of invasive versus echocardiography-derived aortic gradient in patients undergoing TAVI.

Reference: van den Dorpel MMP, Chatterjee S, Adrichem R, Verhemel S, Kardys I, Nuis RJ, Daemen J, Ren CB, Hirsch A, Geleijnse ML, Van Mieghem NM. Prognostic value of invasive versus echocardiography-derived aortic gradient in patients undergoing TAVI. EuroIntervention. 2025 Apr 21;21(8):e411-e425. doi: 10.4244/EIJ-D-24-00341. PMID: 40259836; PMCID: PMC11995293.