An Age-Based Analysis of Transcatheter and Surgical Outcomes in Low-Risk Patients Undergoing Aortic Valve Replacement for Aortic Valve Stenosis

T. Mesar¹, D. Ahmad², D. Kliner², D. Serna-Gallegos², C. Toma², A. Makani², D. West³, Y. Wang², F. Thoma², I. Sultan^2
1UPMC, Pittsburgh, Pennsylvania ²University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania ³University of Pittsburgh, Valencia, Pennsylvania

Purpose: Transcatheter aortic valve replacement (TAVR) is increasingly utilized in younger patients. The mean age in PARTNER3 trial was 73 years. The benefits of one therapy over another in younger patients remain unclear. We explored the association of age in surgical aortic valve replacement (SAVR) and TAVR outcomes in low-risk patients.

Methods: Retrospective analysis utilizing institutional combined STS and TVT databases of low-risk patients (STS Score < 4.0) undergoing isolated SAVR or TAVR for degenerative aortic stenosis from 1/2010 to 12/2022. Patients were divided into 3 cohorts: Young - < 65 years (Y), Intermediate - 65-74 years (I), and Old - >75 years (O). We excluded valve-in-valve TAVR or redo SAVR, endocarditis, and cases requiring concomitant aortic, coronary, non-aortic valve, or root surgery, except root enlargement. Primary outcome was all-cause mortality at 5 years (ACM5), and the secondary outcome was a composite outcome including ACM5, stroke, and readmission for heart failure. A Cox proportional hazards regression model was utilized to determine hazard ratios.

Results: We identified 3764 patients, 725 (19.2%) in Y, 1259 (33.4%) in I, and 1780 (47.3%) in O. The proportion of TAVR increased from 10.5% in Y, 42.0% in I, to 75.8% in O. Median STS Score increased from 0.92 (IQR 0.67, 1.40) for cohort Y, to 1.61 (IQR:1.15, 2.40) for I, and 2.50 (IQR: 1.80, 3.20) for O, p< 0.001. In unadjusted analysis, ACM5 was higher in TAVR vs. SAVR in cohort Y (25.0% vs. 7.9%, p< 0.001), and secondary outcome was also worse in TAVR (42.1% vs. 28.7%, p=0.016). In Cohort I, ACM5 was higher in TAVR (15.7% vs. 10.9%, p=0.013), with no difference in secondary outcome (33.0% vs. 35.4%, p=0.361). In Cohort O, ACM5 was higher in TAVR (20.8% vs. 14.6%, p=0.0045), but secondary outcome was better for TAVR (35.8% vs. 47.8%, p< 0.001). Odds for death at 5 years in cohort Y were significantly higher in TAVR compared to SAVR, OR: 3.635, 95%CI[1.792-7.372], p=0.002; however, in cohort I no difference was observed OR: 1.373 95%CI[0.851, 2.214], p=0.164. Low-risk patients above 75 years tended to have better survival rate with SAVR (ACM5 for TAVR OR:1.998, 95%CI[1.270, 3.144], p=0.002). The presence of bicuspid versus tricuspid valve did not affect outcomes.

Conclusion: TAVR in patients below 65 years of age was associated with a 3-times higher all-cause mortality at 5 years compared to SAVR. No difference was observed in intermediate age patients. Until a randomized controlled trial is performed, caution should be exerted when offering TAVR to young low-risk patients with aortic stenosis.

Identify the source of the funding for this research project: none