Division of Advanced Manufacturing, Graduate School at Shenzhen, Tsinghua University , Shenzhen , China.
Cardiac surgery Center, Beijing Anzhen Hospital, Capital Medical University , Beijing , China.
Comput Assist Surg (Abingdon). 2019 Oct;24(sup1):89-95. doi: 10.1080/24699322.2018.1560099. Epub 2019 Feb 11.
A novel pulsatile assist device, intra-ventricular assist device, was proposed to address various disadvantages existing in conventional pulsatile assist device, such as the large size, accessories and reduced pulsatility. The assist device was designed, fabricated and implanted into the sac from left ventricular apex in a home-designed mock circulatory system. In vitro test was carried out and results demonstrated that the response time did not vary with the heart rate, and co-pulsatiled synchronously with native heart by electrocardiograph. The key parameter, stroke volume of proposed device was precisely measured under different afterloads (60, 80, 100, and 120 mmHg), drive pressure (from 90 to 300 mmHg at 30 mmHg intervals), and heart rate (45-150 beats per minute). The measurement results revealed that the output characteristics of device, stroke volume increased with increasing drive pressure but decreased with increasing peripheral resistance, were consistent with the native heart. The proposed pump was then coupled with mock system that was set to a heart failure mode and the circulatory responses were tested. Results showed that the device improved left ventricular pressure from 106 to 158 mmHg, and stroke volume from 25.5 to 44 ml at 90 bpm.
一种新型的脉动辅助装置，即心室内辅助装置，被提出以解决传统脉动辅助装置存在的各种缺点，如体积大、附件多和脉动性降低等。该辅助装置在一个自行设计的模拟循环系统中，从左心室心尖处被设计、制造并植入囊中。进行了体外测试，结果表明，响应时间不随心率变化，并且通过心电图与原生心脏同步搏动。在不同的后负荷（60、80、100 和 120mmHg）、驱动压力（从 90 到 300mmHg，每隔 30mmHg）和心率（45-150 次/分钟）下，精确测量了所提出装置的关键参数——每搏输出量。测量结果表明，装置的输出特性，即每搏输出量随驱动压力的增加而增加，随外周阻力的增加而降低，与原生心脏一致。然后，将该泵与模拟系统耦合，该模拟系统被设置为心力衰竭模式，并测试循环响应。结果表明，该装置将左心室压力从 106mmHg 提高到 158mmHg，每搏输出量从 25.5ml 提高到 90bpm 时的 44ml。
