Umeki Akihide, Nishimura Takashi, Takewa Yoshiaki, Ando Masahiko, Arakawa Mamoru, Kishimoto Yuichiro, Tsukiya Tomonori, Mizuno Toshihide, Kyo Shunei, Ono Minoru, Taenaka Yoshiyuki, Tatsumi Eisuke
Department of Cardiothoracic Surgery, The University of Tokyo, Tokyo, Japan.
J Artif Organs. 2013 Jun;16(2):119-28. doi: 10.1007/s10047-012-0682-0. Epub 2013 Jan 17.
Aiming the 'Bridge to Recovery' course, we have developed a novel left ventricular assist device (LVAD) controlling system. It can change the rotational speed of the continuous flow LVAD, EVAHEART, synchronized with the cardiac beat. Employing this system, we have already demonstrated that myocardial oxygen consumption (MVO2), which is considered to be equivalent to native heart load, changes in the hearts of normal goats. Herein, we examined changes in goats with acute ischemic heart failure. We studied 14 goats (56.1 ± 6.9 kg) with acute ischemic heart failure due to coronary microsphere embolization. We installed the EVAHEART and drive in four modes: "circuit-clamp", "continuous support", "counter-pulse", and "co-pulse", with 50 and 100 % bypass. In comparison to the circuit-clamp mode, MVO2 was reduced to 70.4 ± 17.9 % in the counter-pulse mode and increased to 90.3 ± 14.5 % in the co-pulse mode, whereas it was 80.0 ± 14.5 % in the continuous mode, with 100 % bypass (p < 0.05). The same difference was confirmed with 50 % bypass. This means that we may have a chance to change the native heart load by controlling the LVAD rotation in synchrony with the cardiac rhythm, so we named our controller as the Native Heart Load Control System (NHLCS). Employing changeable MVO2 with NHLCS according to the patient's condition may provide more opportunity for native heart recovery with LVAD, especially for patients with ischemic heart diseases.
针对“康复之桥”课程，我们开发了一种新型的左心室辅助装置（LVAD）控制系统。它可以改变连续流LVAD（EVAHEART）的转速，使其与心跳同步。利用该系统，我们已经证明，在正常山羊的心脏中，被认为等同于天然心脏负荷的心肌耗氧量（MVO2）会发生变化。在此，我们研究了急性缺血性心力衰竭山羊的变化情况。我们研究了14只因冠状动脉微球栓塞导致急性缺血性心力衰竭的山羊（体重56.1±6.9千克）。我们以四种模式安装了EVAHEART并进行驱动：“回路钳夹”、“持续支持”、“反搏”和“同步搏动”，旁路分别为50%和100%。与回路钳夹模式相比，反搏模式下MVO2降低至70.4±17.9%，同步搏动模式下增加至90.3±14.5%，而在100%旁路的持续模式下为80.0±14.5%（p<0.05）。50%旁路时也证实了同样的差异。这意味着我们可能有机会通过与心律同步控制LVAD旋转来改变天然心脏负荷，因此我们将我们的控制器命名为天然心脏负荷控制系统（NHLCS）。根据患者情况利用NHLCS改变MVO2可能为使用LVAD的天然心脏恢复提供更多机会，尤其是对于缺血性心脏病患者。
