Van Nooten G J, Taeymans Y, Verdonck P
Institute of Biomedical Engineering, University of Ghent, Belgium.
J Heart Valve Dis. 1997 Sep;6(5):546-9.
Before the development of standard aortic valve replacement, Hufnagel treated aortic insufficiency by implanting a ball-valve prosthesis in the descending thoracic aorta. In a patient who, after four major thoracic procedures, ultimately received two mechanical bileaflet valves in series (one in the ascending and one in the descending aorta), the downstream prosthesis became progressively immobilized, with total blockage of the leaflets in the open position due to insufficient transvalvular negative pressure gradient. After evaluation of this particular situation in an experimental model, we predicted blockage of the downstream prosthesis, once the ascending valve had regained normal function, and easily cleared the blockage of the distal valve by removing the two leaflets using balloon inflation. Normal circulation was clinically restored in three separate steps. (a) Normal function was re-established surgically in the ascending aorta position. (b) A second thoracotomy was avoided by endovascular dislocation of both blocked descending thoracic leaflets through endovascular balloon inflation. (c) Both leaflets embolized to the level of the left common iliac artery, where the nearly intact leaflets were removed surgically, finally creating a near-normal circulatory situation.
在标准主动脉瓣置换术发展之前，胡夫纳格尔通过在降主动脉植入球瓣假体来治疗主动脉瓣关闭不全。在一名患者身上，经过四次大的胸部手术，最终串联植入了两个机械双叶瓣（一个在升主动脉，一个在降主动脉），下游的假体逐渐固定，由于跨瓣负压梯度不足，瓣叶在开放位置完全阻塞。在实验模型中评估了这种特殊情况后，我们预测一旦升主动脉瓣恢复正常功能，下游假体会发生阻塞，并通过球囊扩张移除两个瓣叶轻松清除远端瓣膜的阻塞。通过三个独立步骤在临床上恢复了正常循环。（a）在升主动脉位置通过手术重建正常功能。（b）通过血管内球囊扩张使降主动脉内两个阻塞的瓣叶发生血管内脱位，从而避免了第二次开胸手术。（c）两个瓣叶栓塞至左髂总动脉水平，在那里通过手术移除几乎完整的瓣叶，最终形成了接近正常的循环状态。
