PubMed Health⌕ Search

Biomedical subjects

Motonobu Nishimura

Publications and source records attributed to Motonobu Nishimura.

23 records · Page 2Linked to original sources
PubMed2002

Arch-first technique for aortic arch aneurysm repair through median sternotomy.

We describe a modified arch-first technique for total arch replacement through median sternotomy. This technique involves a short period of circulatory arrest (less than 30 minutes) and subsequent anterior cerebral perfusion. It does not require cannulation of the carotid vessels, which can cause cerebral thromboembolism, and it enables anterior cerebral perfusion to be resumed after a relatively short period of circulatory arrest. This appears to be a useful technique to reduce cerebral complications in complicated arch reconstruction operation for patients with severely atherosclerotic carotid vessels.

Aorta, Thoracic↗
PubMed2002

[Left ventricular assist system].

Two types of artificial heart, the total artificial heart (TAH) and ventricular assist system (VAS), have been utilized in patients with end-stage heart failure waiting for heart transplantation (bridge to transplantation). The TAH is a system to replace the native heart, whereas the VAS is a system to support the left ventricle (LVAS), right ventricle (RVAS), or both ventricles (BVAS) while maintaining native cardiac function. There are two types of VAS, paracorporeal VAS and implantable VAS. Implantable VAS devices such as Novacor LVAS and HeartMate LVAS are only available for LVAS, although paracorporeal VAS, such as Toyobo VAS, Zeon VAS, and Thoratec VAS, are available for RVAS, LVAS, or BVAS. Due to recent advances in the VAS, the "patient discharge program" from hospital has been promoted for improvement of the quality of life (QOL) and reduction of medical costs. VAS also have been utilized as "bridges to recovery" for native hearts or for "semipermanent use" in patients without indications for heart transplantation, and superior clinical results of VAS therapy compared with conservative therapy have been reported in terms of one-year survival rate and improvement of QOL. Recently, several inexpensive VAS systems with an axial or centrifugal pump have been developed and the initial clinical trials of these systems have recently started in Western countries. Another remarkable technological advance in VAS is the Lion Heart (Arrow) which is a totally implantable VAS system the includes an energy transmission system. We expect that recent technological progress in VAS will improve the survival and QOL in patients with end-stage heart failure.

Heart Failure↗
PubMedDate not supplied

Improvement of bypass circuit biocompatibility: comparison and combination of heparin-coated circuit and nitric oxide gas infusion.

OBJECTIVES: Nitric oxide (NO) gas infusion to the oxygenator, as well as heparin-coated bypass circuits, have been reported to attenuate blood activation induced by the interaction with the artificial surfaces of an extracorporeal bypass circuit. Using a mock circulation model, we compared the effect of each and also evaluated the effect of their combination on attenuating bypass-induced blood activation. METHODS: A miniature closed bypass circuit was primed with diluted fresh human blood and perfused for 180 minutes using a centrifugal pump. NO gas (0, 50, or 100 ppm) was infused to the oxygenator sweep gas of either a non-heparin-coated or a heparin-coated circuit. Platelet counts, beta-thromboglobulin, platelet factor 4, complement-3 activation products and granulocyte elastase were measured at 0, 30, 60, 120, and 180 minutes after starting the perfusion. RESULTS: One hundred ppm of NO was statistically equivalent to the heparin-coated circuit for attenuating bypass-induced blood activation, and a combination of the two significantly surpassed the results of either modification alone. Fifty ppm of NO alone provided only a slight attenuation of blood activation as compared with the non-heparin-coated circuit, though the difference was not significant. A combination of 50 ppm NO and the heparin-coated circuit did not significantly enhance the effects of the heparin-coated circuit alone. CONCLUSIONS: The combination of NO gas infusion and heparin-coated circuits appears to be a useful and promising modification for enhancing the attenuation of bypass-induced blood activation, though the optimal dose of NO infusion in terms of effectiveness and adverse effects to the whole body remains to be established.

Anticoagulants↗
PubMedDate not supplied

Avoidance of full-sternotomy: effect on inflammatory cytokine production during cardiopulmonary bypass in rats.

BACKGROUND AND AIM OF THE STUDY: Although open heart operations via a mini-sternotomy or mini-thoracotomy are considered "less invasive" cosmetically and are hopeful for early social recovery, clinical experiences have not shown less invasiveness toward systemic inflammatory response, because of the wide variety of patients and operative procedures encountered. We examined the effect of a mini-sternotomy on an inflammatory response during a cardiopulmonary bypass (CPB) procedure performed in rats. METHODS: Thirty-two adult Sprague-Dawley (SD) rats, each of which underwent a 120-minute CPB, were randomly divided into four groups according to the method of exposing the pericardial cavity; no sternotomy (Group N [0 cm], n = 8), right para-sternal thoracotomy (Group P [2 cm], n = 8), lower mini-sternotomy (Group M [2 cm], n = 8), and full-sternotomy (Group F [4 cm], n = 8). Blood samples were obtained (1) just prior to the initiation of CPB, and then (2) 30, (3) 60, and (4) 120 minutes after the initiation of CPB. RESULTS: Thirty minutes after the initiation of CPB, there were significant differences in plasma interleukin [IL]-6 levels between groups, except for Groups P and M; whereas at 60 minutes the only significant difference occurred between Groups N and F, and at 120 minutes there were no significant differences between any of the groups. Further, plasma IL-8 levels were not significantly different at each sampling point between all of the groups. CONCLUSIONS: These results first demonstrate experimentally that the avoidance of a full-sternotomy can be considered a less invasive strategy in terms of reducing the systemic inflammatory response that accompanies a shorter CPB duration.

Animals↗