Impact of Valve Size on Prosthesis-Patient Mismatch and Aortic Valve Gradient After Transcatheter versus Surgical Aortic Valve Replacement

Objective: Limited data is available about the effect of implanted valve size on prosthesis-patient mismatch (PPM) incidence and aortic gradient (AG) after transcatheter aortic valve replacement (TAVR) and surgical aortic valve replacement (SAVR). We compared PPM incidence and postprocedural AG between TAVR and SAVR patients considering the impact of implanted valve size. Methods: From March 20, 2012, to September 30, 2015, 563 consecutive patients underwent TAVR (n = 419) or isolated SAVR (n = 144). Postprocedural transthoracic echocardiography was obtained within 30 days; AG, effective orifice area (EOA), and EOA index were calculated. Results: A total of 381 patients in TAVR group and 82 patients in SAVR group were included. Mean preoperative AG and mean aortic valve area were not significantly different between the 2 groups. Postprocedural AG was significantly lower in TAVR than SAVR group, 7.74 +/- 5.39 versus 14.27 +/- 8.16 (P < 0.001). Between patients who had TAVR and SAVR with a valve size <= 23 mm, SAVR patients were 3 times more likely to have greater than mild AG after the procedure, OR: 3.1 (95% CI, 1.1 to 8.9) (P < 0.001). PPM incidence was significantly higher in SAVR group than TAVR group, 44 (53.7%) versus 112 (29.4%), OR = 2.8 (95% CI, 1.7 to 4.5) (P < 0.001). The PPM incidence was also higher in SAVR group than TAVR group among those who had the procedures with a valve size <= 23 mm, 35 (64.8%) versus 56 (47.9%), OR = 2 (95% CI, 1.1 to 3.9) (P = 0.048). Postprocedural outcomes were comparable between the 2 groups. Conclusions: In comparison to SAVR, TAVR is associated with less PPM and lower AG, especially in patients receiving a valve size <= 23 mm.