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.
Direct Ex Vivo Measurement of the Real Geometric Orifice Area to Assess the Hemodynamic Performance of Bioprosthetic Heart Valves
