Asymmetry in the Implantation of Self-Expanding Valves in TAVR: Evolution at 5 Years

Severe aortic stenosis is frequently associated with significant and irregular calcification, which tends to be more present in the non-coronary sinus. Incomplete valve expansion, observable through fluoroscopy after implantation, can lead to alterations in the hemodynamic profile and favor structural deterioration of the percutaneous aortic valve.

Currently, both the true impact of incomplete expansion and the degree of expansion required to result in hemodynamic alterations or future adverse events remain unclear.

In this context, researchers conducted an analysis on 1216 patients who underwent transcatheter aortic valve replacement (TAVR) with SAPIEN or SAPIEN 3 balloon-expandable valves. The asymmetry index was assessed using the following formula (%): (greater height/lesser height) – 1 × 100. The result was considered high when it exceeded 5.5%.

A high asymmetry index (HAI) was observed in 206 patients (17.2%). Average patient age was 81 years, and 34% of subjects were women, with an STS mortality risk score of 4.3%. Most patients were functional class III-IV.

Seven percent of cases involved bicuspid valves, with an aortic valve area of 0.78 cm² and an ejection fraction of 55%. The average annular diameter was 25 mm. Patients with a HAI had higher gradients (65 mmHg vs. 60 mmHg for peak gradient and 43 mmHg vs. 39 mmHg for mean gradient, respectively).

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A mean gradient ≥20 mmHg was more frequent in patients with HAI (18.7% [n = 39] vs. 1.2% [n = 12]; odds ratio [OR]: 19.34; 95% confidence interval [CI]: 9.32-40.16; P <0.001), and so was the presence of moderate to higher paravalvular leak (5.7% [n = 12] vs. 0.3% [n = 3]; OR: 19.70; 95% CI: 5.35-72.58; P <0.001).

In the receiver operating characteristics (ROC) curve analysis, asymmetry proved to be an excellent predictor of hemodynamic performance alterations in balloon-expandable valves (0.88; 95% CI: 0.84-0.92; P <0.001), with a cut-off point >5%, which had a 77-% sensitivity and an 86-% specificity.

Structural deterioration was similar between groups (3.9% vs. 3.6%; OR: 1.21; 95% CI: 0.51-2.86; P = 0.670). At 30 days, there were no differences in all-cause mortality or cardiovascular mortality (1.4% vs. 1.7% and 1% vs. 1.3%, respectively). There were also no differences in the incidence of mortality and stroke at one year.

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At 5 years of follow-up, there were no differences in all-cause mortality or cardiac mortality (21.1% vs. 26.2% and 13.9% vs. 17.6%, for HAI and for those without asymmetry, respectively).

Conclusion

The asymmetric expansion of balloon-expandable valves was associated with hemodynamic alterations in their functioning but did not impact long-term clinical outcomes.

Original Title: Asymmetrical Expansion of Balloon-Expandable Transcatheter Aortic Valve Prostheses Implications for Valve Hemodynamic and Clinical Outcomes.

Reference: Annette Maznyczka, et al. JACC Cardiovasc Interv. 2024;17:2011–2022.