In this study, we developed a new miniature motor-driven pulsatile left ventricular assist device (LVAD) for implantation into a Japanese patient of average build by means of computer-aided design and manufacturing (CAD/CAM) technology. A specially designed miniature ball-screw and a high-performance brushless DC motor were used in an artificial heart actuator to allow miniaturization. A blood pump chamber (stroke volume 55 ml) and an inflow and outflow port were designed by computational fluid dynamics (CFD) analysis. The geometry of the blood pump was evaluated using the value of index of pump geometry (IPG) = (Reynolds shear stress) x (occupied volume) as a quantitative index for optimization. The calculated value of IPG varied from 20.6 Nm to 49.1 Nm, depending on small variations in pump geometry. We determined the optimum pump geometry based on the results of quantitative evaluation using IPG and qualitative evaluation using the flow velocity distribution with blood flow tracking. The geometry of the blood pump that gave lower shear stress had more optimum spiral flow around the diaphragm-housing (D-H) junction. The volume and weight of the new LVAD, made of epoxy resin, is 309 ml and 378 g, but further miniaturization will be possible by improving the geometry of both the blood pump and the back casing. Our results show that our new design method for an implantable LVAD using CAD/CAM promises to improve blood compatibility with greater miniaturization.
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http://dx.doi.org/10.1007/s10047-003-0223-y | DOI Listing |
Multimed Man Cardiothorac Surg
January 2025
• Department of Cardiac Sciences, King Abdulaziz Medical City, Ministry of National Guard Health Affairs, Jeddah, Saudi Arabia • King Abdullah International Medical Research Center, Ministry of National Guard Health Affairs, Jeddah, Saudi Arabia • College of Medicine, King Saud bin Abdulaziz University for Health Sciences, Ministry of National Guard Health Affairs, Jeddah, Saudi Arabia.
Prostaglandin E1 is a potent vasodilator that prevents the ductus arteriosus from closing. Its use in neonates with cyanotic heart defects has revolutionized the management of children with cyanotic heart defects. Although the use of prostaglandin E1 is a temporary solution, the establishment of dependable pulmonary blood flow is of paramount importance.
View Article and Find Full Text PDFDrug Des Devel Ther
January 2025
School of Medicine, Kyungpook National University and Department of Clinical Pharmacology and Therapeutics, Kyungpook National University Hospital, Daegu, 41944, Republic of Korea.
Background: YYD601 is a new dual delayed-release formulation of esomeprazole, developed to enhance plasma exposure and prolong the duration of acid suppression.
Purpose: This study aimed to evaluate the safety, pharmacokinetic (PK), and pharmacodynamic (PD) profiles of YYD601 20 mg following single and multiple oral administrations in healthy, fasting adult Koreans, and to compare these outcomes to those of the conventional esomeprazole 20 mg capsule.
Methods: A randomized, open-label, two-period crossover study was conducted in 28 participants, who were divided into two treatment groups: one group received YYD601 20 mg, and the other received conventional esomeprazole 20 mg, once daily for five consecutive days.
J Diabetes Res
January 2025
Diabetes Center, Dallah Hospital, Riyadh, Saudi Arabia.
The study was aimed at assessing the role of the MiniMed780G system of glycemic control before, during, and after Ramadan among people with Type 1 diabetes (PwT1D). This is a single-center retrospective analysis of MiniMed780G system users aged 14 years and above whose glycemic profiles were collected from February 21 to May 20, 2023, which corresponds to the Hijri months of Sha'ban, Ramadan, and Shawwal 1444/1445. Data was collected, processed, and analyzed in the framework of the Medtronic Galaxy service of the One Hospital Clinical Service (OHCS) program in Dallah Hospital, Riyadh, Saudi Arabia.
View Article and Find Full Text PDFBioeng Transl Med
January 2025
Research Institute of Transplant Medicine, Tianjin First Central Hospital, School of Medicine, Nankai University Tianjin China.
Pump is a vital component for expelling the perfusate in small animal isolated organ normothermic machine perfusion (NMP) systems whose flexible structure and rhythmic contraction play a crucial role in maintaining perfusion system homeostasis. However, the continuous extrusion forming with the rigid stationary shaft of the peristaltic pumps can damage cells, leading to metabolic disorders and eventual dysfunction of transplanted organs. Here, we developed a novel biomimetic blood-gas system (BBGs) for preventing cell damage.
View Article and Find Full Text PDFAm J Case Rep
January 2025
Department of Cardiovascular Surgery, Fujian Heart Medical Center, Union Hospital, Fujian Medical University, Fuzhou, Fujian, China.
BACKGROUND Acute intramural hematoma (IMH) of the ascending thoracic aorta and aortic arch is a life-threatening condition, particularly in elderly patients with comorbidities, due to its risk of progression and rupture. Unlike aortic dissection, IMH lacks an intimal tear, influencing both clinical presentation and treatment strategy. This report describes a 74-year-old hypertensive woman with type A IMH and a penetrating atherosclerotic ulcer (PAU), managed with a hybrid surgical approach that combines external Dacron wrapping of the ascending aorta and endovascular stenting of the aortic arch with in-situ fenestration of the supra-aortic arteries.
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