Three-Year Outcomes of Mitral Valve-in-Valve Therapy with Balloon-Expandable Valves in the United States

Courtesy of Dr. Juan Manuel Pérez.

Mitral Valve-in-Valve (MViV) implantation with balloon-expandable valves has become a solid alternative for patients with degenerated mitral bioprostheses. However, evidence regarding its medium- and long-term outcomes remains limited. This study assessed three-year survival, cerebrovascular events, and need for mitral reintervention in patients who underwent MViV in the United States.

Researchers included a total of 5971 patients (mean age 72.9 ± 11.4 years; 57.9% women) who underwent the procedure between June 2015 and March 2024. All procedures were performed via the transseptal approach using SAPIEN 3 (64.9%), SAPIEN 3 Ultra (23.5%), or Ultra RESILIA (11.6%) valves, in sizes of 29 mm (51.1%), 26 mm (42.3%), 23 mm (6.6%), and 20 mm (0.1%). Notably, 75.7% of patients had moderate or greater mitral stenosis, and 53.2% had moderate or greater mitral regurgitation, with mixed valve dysfunction frequently observed.

The mitral valve area was 1.1 cm² (interquartile range [IQR] 0.8–1.7), the mean gradient was 13.1 ± 6.2 mmHg, and the average left ventricular ejection fraction (LVEF) was 55.1 ± 11.7%. According to the STS score, 23.5% were classified as low risk (< 4), 35.1% as intermediate risk (4–8), and 41.5% as high risk (> 8). The median follow-up was 377 days (IQR 57–698). The primary endpoint was all-cause mortality at three years; secondary endpoints included stroke, mitral reintervention, New York Heart Association (NYHA) functional class, and quality of life (Kansas City Cardiomyopathy Questionnaire [KCCQ] score).

The overall three-year mortality was 31.9%, with significant differences according to STS risk: 15.8% in the low-risk group, 23.3% in intermediate risk, and 44.5% in high risk (p <0.0001). Stroke rates were 7.6%, 8.4%, and 11.4%, respectively (p = 0.002 between low and high risk), while reintervention rates remained low across all groups (3.8%, 3.0%, and 2.8%; p = 0.71).

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Elective procedures were associated with lower three-year mortality compared to non-elective procedures (28.2% vs. 43.3%; p <0.0001). The strongest predictors of three-year mortality were the need for dialysis, presence of cardiogenic shock, and immunocompromised status at admission. The proportion of patients in NYHA class III/IV dropped from 81.3% to 13.7% at one year, and the median KCCQ score improved by 40 points, with no meaningful differences between STS risk groups.

Conclusion

In conclusion, mitral valve-in-valve therapy with balloon-expandable valves shows good clinical durability at three years, with low reintervention rates and sustained improvements in quality of life. Survival was higher in patients with low STS scores and those undergoing elective procedures. In contrast, non-elective interventions and patients with advanced heart failure and multiorgan dysfunction had the highest mortality rates, highlighting the importance of early detection and timely intervention. Reintervention rates at three years remained low regardless of STS score.

Original Title: 3-Year Outcomes of Mitral Valve-in-Valve Therapy Using Balloon-Expandable Transcatheter Valves in the United States.

Reference: Eleid MF, Krishnaswamy A, Kapadia S, et al. JACC: Cardiovascular Interventions, Volumen 18, pp. 1454–1466, 2025.