Division of Cardiovascular Surgery, University of Zürich, Rämistrasse 100, Zürich, Switzerland.
Eur Heart J. 2011 Apr;32(7):878-87. doi: 10.1093/eurheartj/ehq445. Epub 2010 Dec 9.
The Medtronic Engager™ aortic valve bioprosthesis is a self-expanding valve with support arms facilitating anatomically correct positioning and axial fixation. Valve leaflets, made of bovine pericardium, are mounted on a Nitinol frame. Here, we report the first in man study with this new implant (Trial Identifier NCT00677638).
Thirty patients (mean age 83.4 ± 3.8 years; 83% female) with tricuspid aortic valve stenosis were included in the study. Mean logistic EuroSCORE was 23.4 ± 11.9. Mean aortic annulus diameter was 21.8 ± 1.4 mm. For this study, the Engager was available in only one size (23 mm), to fit aortic annuli of 19-23 mm. Standard transapical valve implantation was performed using pre-dilation of the aortic valve and rapid ventricular pacing during balloon valvuloplasty and most valve deployments. Accurate valve placement was achieved in 29/30 cases (97%). Post-implant peak-to-peak gradient was 13.3 ± 9.3 mmHg. In 80% of the patients, no more than grade I paravalvular leakage was observed, in 13% grades I-II and in 3% grade II. Three patients (10%) required permanent pacemaker implantation for higher-degree or complete atrioventricular block. Four dissections (13%) occurred during positioning of the valve and were treated surgically in three cases. Thirty-day and in-hospital mortality were 20% and 23%, respectively, and 6-month survival was 56.7%. No structural failure occurred for up to 1 year.
This series established the feasibility of implanting a novel self-expanding transapical aortic valve prosthesis predictably into an anatomically correct position. Observed complications led to complete redesign of the delivery system for upcoming clinical studies with the goal of establishing safety and performance.
美敦力 Engager™ 主动脉瓣生物瓣是一种自扩张瓣膜，带有支撑臂，有助于实现解剖学上正确的定位和轴向固定。瓣叶由牛心包制成，安装在 Nitinol 框架上。在此，我们报告首例使用该新型植入物的人体研究（试验标识符 NCT00677638）。
研究纳入 30 例三叶式主动脉瓣狭窄患者（平均年龄 83.4 ± 3.8 岁，83%为女性）。平均 logistic EuroSCORE 为 23.4 ± 11.9。平均主动脉瓣环直径为 21.8 ± 1.4mm。该研究中，Engager 仅有一种尺寸（23mm），适用于 19-23mm 的主动脉瓣环。采用经心尖标准瓣膜植入术，在主动脉瓣预扩张和球囊瓣膜成形术期间快速心室起搏的情况下进行。29/30 例（97%）患者实现了准确的瓣膜放置。植入后的峰值跨瓣梯度为 13.3 ± 9.3mmHg。在 80%的患者中，观察到的瓣周漏仅为 I 级，13%为 I-II 级，3%为 II 级。3 例（10%）患者因高度或完全房室传导阻滞需要植入永久性起搏器。4 例（13%）在瓣膜定位期间发生夹层，其中 3 例手术治疗。30 天和住院死亡率分别为 20%和 23%，6 个月生存率为 56.7%。在长达 1 年的时间内，未发生结构性瓣膜失效。
该系列研究确立了可预测地将一种新型自扩张经心尖主动脉瓣假体植入到解剖学上正确位置的可行性。观察到的并发症导致输送系统的全面重新设计，以便即将进行的临床研究以确保安全性和性能。
