Abstract 16725: Transcatheter Aortic Valve Implantation in Patients With Severe Aortic Stenosis and Small Aortic Annulus: Propensity-Matched Comparison to Standard Aortic Valve Replacement

Abstract

Background: Few data exist on the results of transcatheter aortic valve implantation(TAVI) in patients with a small aortic annulus(AA) compared to standard aortic valve replacement(SAVR). We sought to examine valve hemodynamics and clinical outcomes of patients with a small AA who underwent TAVI versus SAVR. Methods: Between 2007 and 2011, 46 patients (mean age 79.1±9.4 years) with severe aortic stenosis and an AA diameter <19.5 mm (mean 18.3±0.85 mm) underwent TAVI with a 23-mm Edwards SAPIEN bioprosthesis. These patients were compared to 217 propensity-matched patients who underwent SAVR with a 19-mm valve (78% bioprosthesis). Echocardiographic parameters and clinical outcomes were assessed prior to discharge and at follow-up. Results: There was a greater incidence of postoperative atrial fibrillation (34.6% vs 15.2%, p=0.02), acute kidney injury (12.4% vs 8.7%, p=0.05), and blood product transfusion (83% vs 46%, p<0.001) in the SAVR group compared to the TAVI group. In-hospital mortality was 2.2% in the TAVI group and 6.5% in the SAVR group (p=0.06). One-year survival rate was similar between groups (TAVI 91.3% vs SAVR 87.1%, p=0.20). At hospital discharge, mean transaortic gradients were greater in the SAVR group (18.3 ± 7.2 vs 14.9 ± 9.3 mmHg, p=0.006). Mean indexed effective orifice area (IEOA) was lower in the SAVR group (0.66 ± 0.16 vs 0.84 ± 0.2 cm2/m2, p<0.001), and severe prosthesis-patient mismatch (IEOA < 0.65 cm2/m2) occurred more frequently in the SAVR group (53.3%) than in the TAVI group (9.3%) (p<0.001). Aortic regurgitation(AR) occurred in 72% of the patients in the TAVI group (trivial or mild: 70%, moderate: 2%) compared to 28% of the patients in the SAVR group (trivial or mild in all cases), p<0.001. Echocardiographic results remained unchanged at 1-year follow-up. Conclusion: In patients with severe AS and a small AA, TAVI is associated with lower postoperative morbidity and better valve hemodynamics but a higher incidence of trivial/mild residual AR as compared to SAVR. These results suggest that TAVI is a reasonable alternative to SAVR in elderly patients with small AA.