Transapical sutureless aortic valve implantation under magnetic resonance imaging guidance: Acute and short-term results.
Transapical sutureless aortic valve implantation under magnetic resonance imaging guidance: Acute and short-term results.
复制标题
磁共振成像引导下经心尖无缝合主动脉瓣植入：急性和短期结果。
DOI：
10.1016/j.jtcvs.2014.10.101
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发表时间：
2015
期刊：
影响因子：
--
通讯作者：
Li,Ming
中科院分区：
文献类型：
--
作者：
Horvath,KeithA;Mazilu,Dumitru;Cai,Junfeng;Kindzelski,Bogdan;Li,Ming
目的尽管经导管主动脉瓣置换术的成功率和适用性不断提高，但仍存在两个关键问题：瓣膜的耐用性和辅助植入的理想成像。本研究旨在通过实时核磁共振成像(MRI)引导，研究一种已知耐用性的装置经根尖植入的方法。方法使用一种可自行扩张的镍钛合金支架的无缝合主动脉瓣，该支架可经根尖输送。用1.5T磁共振成像确定60公斤级尤卡坦猪的解剖标志。假体被加载到与MRI兼容的输送设备中，并带有活动导丝以增强可视化。进行了一系列急性可行性实验(n=10)。另外6只动物被允许存活，并在术后90天进行MRI扫描和超声心动图随访。结果瓣膜与MRI相容，无明显的MRI伪影。在短轴切面上可见3个连合支柱，因此很容易避免冠状静脉口阻塞。平均植入时间为65秒。结果显示，植入后的支架稳定性好，心肌灌注和功能保存时间超过90天，射血分数为48%±15%，峰值梯度为17.3±11.3 mm Hg，平均梯度为9.8±7.2 mm Hg。轻度主动脉瓣返流4例，微量返流1例，重度中央喷血1例。在大体检查中评估假体的位置。结论在实时MRI引导下，经心尖入路可安全、快速地植入无缝合的主动脉瓣。植入后的结果显示，假体功能良好，反流最少，并随着时间的推移保持稳定。
ObjectivesDespite the increasing success and applicability of transcatheter aortic valve replacement, 2 critical issues remain: the durability of the valves, and the ideal imaging to aid implantation. This study was designed to investigate the transapical implantation of a device of known durability using real-time magnetic resonance imaging (MRI) guidance.MethodsA sutureless aortic valve was used that employs a self-expanding nitinol stent and is amenable to transapical delivery. MRI (1.5-T) was used to identify the anatomic landmarks in 60-kg Yucatan swine. Prostheses were loaded into an MRI-compatible delivery device with an active guidewire to enhance visualization. A series of acute feasibility experiments were conducted (n = 10). Additional animals (n = 6) were allowed to survive and had follow-up MRI scans and echocardiography at 90 days postoperatively. Postmortem gross examination was performed.ResultsThe valve was MRI compatible and created no significant MRI artifacts. The 3 commissural struts were visible on short-axis view; therefore, coronary ostia obstruction was easily avoided. The average implantation time was 65 seconds. Final results demonstrated stability of the implants with preservation of myocardial perfusion and function over 90 days: the ejection fraction was 48% ± 15%; the peak gradient was 17.3 ± 11.3 mm Hg; the mean gradient was 9.8 ± 7.2 mm Hg. Mild aortic regurgitation was seen in 4 cases, trace in 1 case, and a severe central jet in 1 case. Prosthesis positioning was evaluated during gross examination.ConclusionsWe demonstrated that a sutureless aortic valve can be safely and expeditiously implanted through a transapical approach under real-time MRI guidance. Postimplantation results showed a well-functioning prosthesis, with minimal regurgitation, and stability over time.