Urgent transcatheter aortic valve replacement for severe acute aortic regurgitation following open mitral valve surgery

Transcatheter aortic valve replacement (TAVR) is not currently approved for pure native valve aortic incompetence, and is typically performed on a compassionate basis in selected patients who are at high risk for conventional surgery. We describe the first use of TAVR to treat iatrogenic severe acute pure aortic incompetence following mitral valve surgery. A 71‐year‐old gentleman developed life‐threatening acute aortic regurgitation (AR) within hours of a very challenging fifth open heart mitral valve replacement. Careful inspection of echocardiographic and computed tomographic imaging identified the cause as a disrupted left coronary cusp at the commissure caused by the surgical mitral annular reconstruction. Medical management with afterload reduction failed with recurrent pulmonary edema, and a sixth open heart surgery was deemed prohibitively high risk. The lack of aortic annular calcium onto which anchors a transcatheter valve was a concern for TAVR. However, we postulated that the struts of the mitral valve bioprosthesis would offer some support to the TAVR valve. We opted for a self‐expanding system because of concerns about potential unfavorable interaction between the balloon onto which balloon‐expandable bioprosthesis is mounted and the struts of the mitral bioprosthesis, and because the Evolut R system has additional anchoring points at the crown which might enhance transcatheter valve stability in the non‐calcified annulus, compared with the Edwards Sapien system. Transfemoral TAVR, performed with a Medtronic Evolut R 34 mm system under general anesthesia and using moderately rapid ventricular pacing, was successful with minimal residual AR. On follow‐up 1 month later the patient was asymptomatic, and the aortic and mitral bioprostheses were functioning normally on echocardiogram.     

经导管主动脉瓣置换的介入瓣膜的现状及展望

经导管主动脉瓣置换术（TAVR）经过最近几年快速发展已经取得巨大进步。迄今为止全球接受TAVR的患者数已近3万例,已成为无法耐受传统手术患者的标准备选治疗措施。从目前已临床应用的介入瓣膜到正在实验研究的新型介入瓣膜可以看出,未来介入瓣膜的发展目标是尺寸更小、长期有效、安全性高、并发症少、操作简单及定位精准。随着TAVR的推广,新型介入瓣的研发,操作者经验的积累,以及长期随访的开展,将给TAVR提供更科学的病例选择标准,减少介入手术的相关并发症,提高更安全有效的治疗效果。未来此项技术还会逐渐扩大适用人群的范围,成为代替传统的主动脉瓣置换术举足轻重的治疗措施。     

The design and development of a stented tissue mitral and aortic heart valve replacement for human implantation

A study was conducted into the development of a mitral and aortic heart valve replacement that caters for patients having suffered valve damage due to stenosis or rheumatic fever. The appeal of the valve is that it is constituted from a solid frame housing pericardial tissue leaflets, and allows the patient freedom from post-operative blood-thinning medication. The valve is designed to appeal to patients in developing areas of the world, as it features a clip-in mechanism to secure the valve assembly into the sewing ring, which is stitched in independently of the frame and leaflets. Re-operative valve replacement would then be made possible when the pericardial leaflets began to calcify. Novel aspects of the design added value to the science of heart valve replacements, through the use of sintered chrome cobalt in the valve components, the insights gained into mechanical testing of pericardium, and the patient benefits offered by the complete design. Further work is planned to fatigue test the assembly, undergo animal trials and make the valve available for commercial use.     

Successful transfemoral aortic valve replacement in a bicuspid aortic stenotic valve: Requirements for a safe implant

Although transcatheter aortic valve replacement (TAVR) has been accepted as an attractive alternative for high‐risk patients with severe symptomatic aortic stenosis (AS), patients with congenital bicuspid AS has been typically disqualified for this indication due to an implied risk of device dislocation, distortion, or device malfunctioning. Nonetheless, bicuspid AS is not uncommon and frequently missed by transthoracic echocardiography. We reported an interesting case of a high‐risk patient with severe symptomatic bicuspid AS who underwent successful TAVR and discussed the anatomic requirements for a safe implant in patients with bicuspid AS considered candidates for TAVR. © 2013 Wiley Periodicals, Inc.