Development of percutaneously adjustable pulmonary artery banding device

背景：在先天性心脏病伴肺血流量增加的患者中，肺动脉环扎术已被广泛作为一种姑息性手术。然而，在某些情况下，通过常规手术很难获得最佳的肺血流。因此，经常需要多次手术来重新调整肺动脉带。这种经皮可调的环扎器将被认为是非常有用的。材料：该装置由一个非顺应性气囊组成，外带可以套在肺动脉周围。气球的一端通过导管连接到储气罐上。当通过储液器注入蒸馏水使气球充气时，由于带不顺应，带的内径减小。方法：6只体重10~15 kg的犬，采用一种新型装置，经胸骨正中切开，行肺动脉结扎术。在植入肺动脉环扎器后即刻评估经皮调节环扎带的可能性。在持续监测右室和肺动脉压力的情况下，通过储气罐注入或取出球囊中的蒸馏水，调整肺收缩的程度。结果：右室-肺动脉压差分别为14.3±12.3 mm Hg(注入量0.5ml)、18.8±11.9 mm Hg(1.0m l)、25.9±20.2 mm Hg(1.5m l)。各组间差异无统计学意义。结论：该装置可能是一种有用的替代肺动脉结扎术的装置。进一步的评估是必要的，并且必须确定潜在的临床应用。

Background : In patients with congenital heart defect and increased pulmonary blood flow, pulmonary artery banding has widely achieved as a palliative operation. However, to obtain optimal pulmonary blood flow is difficult by conventional procedure in some cases. Consequently, multiple operations are often necessary to readjust the pulmonary artery banding. The percutaneously adjustable banding device would be thought very useful.Material : The device consists of a noncompliant balloon with outer band that can be snared around the pulmonary artery. One extremity of the balloon is connected by a catheter to a reservoir. When the balloon is inflated by injection of distilled water through the reservoir, internal diameter of the band is decreased, because the band is not compliant. Method : Six dogs (10-15kg) underwent pulmonary artery banding using a new device, by median sternotomy. The possibility of percutaneously adjusting the band was evaluated immediately after implantation of pulmonary artery banding device. The degree of pulmonary constriction was adjusted by injecting or removing distilled water from balloon through the reservoir under constant monitoring of the right ventricular and pulmonary arterial pressures distal to the band. Also, pulmonary arterial diameter was measured by Intravascular Ultrasound.Results : Pressure gradient between right ventricular and pulmonary arterial pressure distal to the band showed 14.3±12.3mmHg (injected volume 0.5ml), 18.8±11.9mmHg (1.0ml), 25.9±20.2mmHg (1.5ml). The value was not significant between each group.Conclusions : This device may be useful alternative to pulmonary artery banding. Further evaluation is necessary and potential clinical applications must be defined.