Badano Luigi P, Pavoni Daisy, Musumeci Sergio, Frassani Romeo, Gianfagna Pasquale, Baldassi Mara, Tursi Vincenzo, Mazzaro Enzo, Zakja Edlira, Fioretti Paolo M, Livi Ugolino
Department of Cardiopulmonary Sciences, A.O. S. Maria della Misericordia, Udine, Italy.
J Heart Valve Dis. 2006 Mar;15(2):238-46.
The use of stented bioprostheses for aortic valve replacement (AVR) in elderly patients with a small aortic annulus may result in unsatisfactory hemodynamic performance of the prosthesis. To overcome this limitation, new bioprostheses have been designed for complete supra-annular implantation, but the actual hemodynamic advantage of the supra-annular implant over the intra-annular has not been fully investigated. Accordingly, the hemodynamic performance of the same stented bioprosthesis (except for sewing ring design) implanted in the supra-annular and conventional intra-annular seating was compared.
Twenty-two patients received an intra-annular implant, and 38 a supra-annular implant. Age (74 +/- 5 versus 76 +/- 5 years, p = 0.54), gender (55% versus 50% males, p = 0.79) and body surface area (1.74 +/- 0.2 versus 1.81 +/- 0.2 m2, p = 0.13) were similar in both subgroups, who underwent echocardiography at 8 +/- 2 and 6 +/- 2 months after surgery, respectively (p = 0.09).
The two patient subgroups had similar preoperative left ventricular outflow tract diameters (2.06 +/- 0.2 and 2.1 +/- 0.2 cm; p = 0.62), average size of implanted prosthesis (21.0 and 21.3 mm; p = 0.44) and mean transprosthetic flow rate (246 +/- 70 and 218 +/- 58 ml/s; p = 0.12). Mean (8 +/- 3 and 19 +/- 8 mmHg, p < 0.0001), and peak (17 +/- 6 and 40 +/- 13 mmHg; p < 0.0001) transprosthetic gradients were lower, and mean effective orifice area (EOA) (1.78 +/- 0.4 and 1.45 +/- 0.5 cm2, p = 0.006) was higher in patients with supra-annular implants than in those with intraannular. The incidence of patient-prosthesis mismatch (EOA index < 0.85 cm2/m2) decreased from 50% to 34% (p < 0.0001), with no case of severe mismatch using the supra-annular implant. During follow up, a left ventricular mass reduction occurred in patients with supra-annular implants (from 225 +/- 110 to 173 +/- 59 g/m2; p < 0.03), but not in patients with intra-annular implants (173 +/- 62 and 186 +/- 64 g/m2; p = 0.87)
The study results showed that, compared to intra-annular implantation, supra-annular implantation of bioprosthetic stented valves in the aortic position was associated with a significantly better hemodynamic performance of the prosthesis and significant regression of left ventricular hypertrophy.
对于主动脉瓣环较小的老年患者，使用带支架生物瓣膜进行主动脉瓣置换（AVR）可能导致瓣膜的血流动力学性能不尽人意。为克服这一局限性，已设计出新型生物瓣膜用于完全瓣环上植入，但瓣环上植入相对于瓣环内植入的实际血流动力学优势尚未得到充分研究。因此，对同一带支架生物瓣膜（除缝合环设计外）分别植入瓣环上和传统瓣环内位置时的血流动力学性能进行了比较。
22例患者接受瓣环内植入，38例接受瓣环上植入。两个亚组的年龄（74±5岁对76±5岁，p = 0.54）、性别（男性分别为55%和50%，p = 0.79）及体表面积（1.74±0.2对1.81±0.2 m²，p = 0.13）相似，两组患者分别在术后8±2个月和6±2个月接受了超声心动图检查（p = 0.09）。
两个患者亚组术前左心室流出道直径相似（2.06±0.2和2.1±0.2 cm；p = 0.62），植入瓣膜的平均尺寸（21.0和21.3 mm；p = 0.44）及平均跨瓣血流速度（246±70和218±58 ml/s；p = 0.12）。瓣环上植入患者的平均（8±3和19±8 mmHg，p < 0.0001）和峰值（17±6和40±13 mmHg；p < 0.0001）跨瓣压差较低，平均有效瓣口面积（EOA）（1.78±0.4和1.45±0.5 cm²，p = 0.006）高于瓣环内植入患者。患者-瓣膜不匹配（EOA指数<0.85 cm²/m²）的发生率从50%降至34%（p < 0.0001），瓣环上植入未出现严重不匹配病例。随访期间，瓣环上植入患者的左心室质量减轻（从225±110降至173±59 g/m²；p < 0.03），而瓣环内植入患者未减轻（173±62和186±64 g/m²；p = 0.87）。
研究结果表明，与瓣环内植入相比，主动脉位置的生物带支架瓣膜瓣环上植入与瓣膜明显更好的血流动力学性能及左心室肥厚的显著消退相关。
