Bates Melissa L, Anagnostopoulos Petros V, Nygard Cole, Torgeson Jenna, Reichert Jamie, Galambos Csaba, Eldridge Marlowe W, Lamers Luke J
Department of Health and Human Physiology, University of Iowa, Iowa City, Iowa, 52242.
Department of Cardiothoracic Surgery, University of Wisconsin School of Medicine and Public Health Madison, Wisconsin, 53792.
Catheter Cardiovasc Interv. 2018 Jul;92(1):78-87. doi: 10.1002/ccd.27593. Epub 2018 Mar 30.
To determine the consequences of an early catheter-based intervention on pulmonary artery (PA) growth and right ventricular (RV) myocardial function in an animal model of branch PA stenosis.
Acute results and safety profiles of deliberate stent fracture within the pulmonary vasculature have been demonstrated. The long-term impact of early stent intervention and deliberate stent fracture on PA growth and myocardial function is not understood.
Implantation of small diameter stents was performed in a pig model of left PA stenosis at 6 weeks (10 kg) followed by dilations at 10 (35 kg) and 18 weeks (65 kg) with intent to fracture and implant large diameter stents. Hemodynamics, RV contractility, and 2D/3D angiography were performed with each intervention. The heart and pulmonary vasculature were histologically assessed.
Stent fracture occurred in 9/12 and implantation of large diameter stents was successful in 10/12 animals with no PA aneurysms or dissections. The final stented PA segment and distal left PA branch origins equaled the corresponding PA diameters of sham controls. Growth of left PA immediately beyond the stent was limited and there was diffuse fibro-intimal proliferation within the distal left and right PA. RV contractility was diminished in the intervention group and the response to dobutamine occurred uniquely via increases in heart rate.
Early stent intervention in this surgically created PA stenosis model was associated with improved growth of the distal PA vasculature but additional investigation of PA vessel physiology and impact on the developing heart are needed.
在分支肺动脉狭窄的动物模型中，确定早期基于导管的干预对肺动脉（PA）生长和右心室（RV）心肌功能的影响。
已证实肺动脉系统内故意支架断裂的急性结果和安全性。早期支架干预和故意支架断裂对PA生长和心肌功能的长期影响尚不清楚。
在6周龄（10kg）的左肺动脉狭窄猪模型中植入小直径支架，然后在10周龄（35kg）和18周龄（65kg）时进行扩张，目的是使支架断裂并植入大直径支架。每次干预时进行血流动力学、RV收缩功能和二维/三维血管造影检查。对心脏和肺血管系统进行组织学评估。
12只动物中有9只发生支架断裂，12只动物中有10只成功植入大直径支架，未出现PA动脉瘤或夹层。最终支架置入的PA节段和左PA远端分支起始处的直径与假手术对照组相应的PA直径相等。支架近端紧邻处的左PA生长受限，左、右PA远端存在弥漫性纤维内膜增生。干预组RV收缩功能减弱，对多巴酚丁胺的反应仅通过心率增加实现。
在这个手术创建的PA狭窄模型中，早期支架干预与远端PA血管系统生长改善相关，但需要对PA血管生理学及其对发育中心脏的影响进行进一步研究。
