Comparison of two valve systems for transapical aortic valve implantation: a propensity score-matched analysis

Several alternative transapical (TA) aortic prostheses for aortic valve implantation (AVI) have recently become available. Data directly comparing the performance of these different TA-AVI valves, however, are sparse. Therefore, we sought to analyse the performance of the better-established balloon-expandable SAPIEN XT (TM) valve system, and compare it with the recently approved self-expandable ACURATE TA (TM) system by means of propensity score (PS) analysis. Samples from a total of 310 consecutive patients treated with transapical transcatheter aortic valve implantation (TAVI) were included (2010-2014). The ACURATE valve was implanted in 40% (n = 131), SAPIEN in 60% (n = 179). To adjust for baseline differences, 1:1 PS matching was used, and resulted in 103 matched pairs. In addition to demographical and clinical variables, potential anatomical confounders (calcification grade: computed tomography (CT) Agatston score; annulus diameter: CT-effective diameter) were included within the PS estimation. For ACURATE- versus SAPIEN-treated patients, the mean age was 83.1 +/- 5.4 vs 79.8 +/- 9.5 (P < 0.001). Mean Society of Thoracic Surgeon scores were 7.7 +/- 4.6 vs 8.1 +/- 6.0 (P = 0.56). PS matching resulted in bias reduction < 0.2, indicating excellent balance and allowing for valid outcome comparison. Device success, 30-day mortality rate and 1-year survival were comparable. Pacemaker and 30-day neurological event rates were not significantly different. The need for post-ballooning was significantly higher in the self-expandable group (40% vs 9%; P < 0.001). Echocardiography upon discharge demonstrated excellent functional outcomes regarding residual paravalvular leaks (ACURATE: 3% vs SAPIEN: 4%, P = 1.0) with slightly higher mean gradients in the ACURATE group (12 +/- 5 mmHg vs 10 +/- 5 mmHg, P = 0.003). The two transapical TAVI devices demonstrated comparable haemodynamic performance and clinical outcome. The self-expandable valve required more frequent post-ballooning without affecting the safety profile.