Abstract 17870: Hemodynamic Performance of Transcatheter Prosthetic Valve is Superior to that of Surgical Prosthetic Valve for Aortic Valve Stenosis with Small Aortic Root

Abstract

Introduction: Surgical aortic valve replacement (SAVR) in a small aortic root is still challenging with regard to the surgical technique and prosthesis size selection, which often causes patient-prosthesis mismatch (PPM). On the other hand, because a prosthetic valve of transcatheter aortic valve replacement (TAVR) is tightly implanted inside a native valve, larger effective orifice area (EOA) may be gained. The aim of this study is to prove that hemodynamic performance after TAVR is superior to that after SAVR. Methods: 160 patients, who underwent SAVR (n=36; age 75.1±5.6 years) and TAVR (n=124; age 82.4±6.8 years) for aortic valve stenosis, were enrolled. Preoperative ECG-gated multi-slice CT (MSCT) and echocardiography immediately before a discharge were performed in all patients. PPM was defined as the effective orifice area index ≤0.85cm2/m2 and we compared and examined hemodynamic performance after TAVR and SAVR. Results: Although the mean body size was significantly smaller (p<.05) in TAVR than that in SAVR (1.44±0.15 vs 1.51±0.20 m2), there were no significant differences in the diameters of annulus (23.2±1.6 vs 23.3±2.8 mm), valsalva sinus (29.8±2.6 vs 29.9±4.4 mm), and ST junction (25.2±2.8 vs 24.8±3.5 mm) on preoperative MSCT findings. Postoperative echocardiography revealed significantly less Vmax (2.2±0.4 vs 2.5±0.5 m/s, p<.0001), less mean pressure gradient (10.1±3.6 vs 14.5±5.0 mmHg, p<.0001), and larger EOA (1.62±0.29 vs 1.45±0.36 cm2, p<.005) in TAVR compared to SAVR, respectively. Consequently, PPM was more frequently in SAVR compared to TAVR (33.3 vs 8.9%; p<.0007). In multivariate analysis in SAVR identified small ST junction with only predictive factor of PPM (odds ratio [OR], 2.08; 95% CI, 1.23-4.36; p<.005; area under the receiver-operating characteristic curve [AUC], 0.84). On the other hand, regarding TAVR, large BSA was only predictive factor of PPM (p<.05). Conclusions: The hemodynamic performance of transcatheter prosthetic valve is superior to that of surgical prosthetic valve in a patient with small aortic root, in particular, small ST junction. TAVR should be considered in patients with anticipated PPM if the surgical risk is similar to TAVR.