Notes

Riding the actual top to acquire a mind: neural crest progression in vertebrates.
Rotating impeller actuated by electromagnet has been a key technological innovation which surpassed earlier limitations of pulsatile pumps. Current impeller design, however, is alien to the functional unit of the human circulatory system and remains a potential cause of adverse prothrombotic events such as hemolysis or pump thrombosis by forcing blood cells to pass over a narrow space available within the rapidly alternating blades attached along its central hub, creating fundamentally a nonphysiologic flow, especially for miniaturized percutaneous blood pumps. Here, we present a biologically inspired, open, helicoid (BiO-H) impeller design for a circulatory assist device that has a fundamentally different footprint from the conventional Archimedean screw-based impeller designs by implementing new design features inspired by an avian right atrioventricular valve. Design parameters including an inner diameter, helix height, overall height, helix revolutions/pitch, blade length, blade thickness, introductory blade angle, number of blades, and blade shape were optimized for maximum output volumetric flow rate through the parametric analysis in computational fluid dynamics simulation. BiO-H shows an improved flow path with 2.25-fold less cross-sectional area loss than the conventional impeller designs. BiO-H with a diameter of 15 mm resulted in a maximum flow rate of 25 L/min at 15,000 revolutions per minute in simulation and showed further improved pressure-flow relationship in benchtop experiments. The design shows promise in increasing flow and could serve as a new impeller design for future blood pumps.This study was performed to evaluate the incidence and outcome of patients with ventricular assist devices (VADs) undergoing abdominal surgery at our institution. A total of 604 adult patients who underwent VAD implantation between February 2004 and February 2018 were analyzed retrospectively with a median follow-up time of 66 (6-174) months. Thirty-nine patients (6.5%) underwent abdominal surgery. Elective surgical procedures were performed in 22 patients (56.4%), mainly for abdominal wall hernia repairs, partial colectomies, and cholecystectomies. Early after elective abdominal surgery no patient died, resulting in a median survival of 23 (1-78) months. Emergency surgery was performed in 17 patients (43.6%). The most common emergency indications were intestinal ischemia and/or perforation. Eight patients undergoing emergent surgery (44.4%) died within the first 30 days after primary abdominal operation, mainly due to sepsis and consecutive multiple organ failure, resulting in a dismal median survival of one month (0-52). Patients undergoing abdominal surgery had significantly lower rates of realized heart-transplantation (p = 0.031) and a significantly higher rate of VAD exchange, before or after abdominal surgery, due to thromboses or infections (p = 0.037). Nonetheless, overall survival after primary VAD implantation in these patients (median 38 months; 0-107) was not significantly impaired when compared to all other patients undergoing VAD implantation (median 30 months; 0-171). In summary, elective abdominal surgery can be performed safely when well planned by an experienced multidisciplinary team. Abdominal complications in VAD patients requiring emergent surgery, however, lead to a significant increase in short-term morbidity and a high 30-day mortality rate.Antithrombotic optimization with a glycoprotein IIb/IIIa inhibitor has been used for the treatment of suspected pump thrombosis, but available literature with tirofiban is lacking. This study aims to describe the use of tirofiban for suspected pump thrombosis. This was a single-center cohort study of left ventricular assist device patients who received tirofiban for the treatment of suspected pump thrombosis from January 1, 2016 to July 31, 2017. Tirofiban was initiated at 0.1 μg/kg/min in patients with normal renal function and subsequent dose adjustments for altered renal function or history of bleeding were employed. Success was defined as resolution of lactate dehydrogenase back to patients' known baseline. Fourteen patients were included for 16 total instances of tirofiban use during the time period. Tirofiban was continued for a median of 5 days (range 0.3-35 days). Successful treatment was achieved in 12 of the 16 tirofiban uses (75%). Seven bleeding events occurred while on therapy, two major and five minor. This study showed a majority of patients achieved success with tirofiban for suspected pump thrombosis. For patients who are not current candidates for pump exchange or transplant, tirofiban may be considered a therapeutic medical management option.Neurohormonal blockade (NHB) is the mainstay of therapy for patients with systolic heart failure (HF). However, the efficacy in patients with left ventricular assist devices (LVADs) remains unknown. Of all, 114 LVAD patients (57 [48, 65] years old and 78% male) were enrolled and followed during the early period (6 months after index discharge), and 98 were followed during the late period (6-12 months following index discharge). Of them, 46% were on beta-blocker (BB), 49% on angiotensin-converting enzyme inhibitor (ACEi) and/or angiotensin II receptor blocker (ARB), and 51% on aldosterone antagonist at baseline. Prevalence of BB and ACEi/ARB use increased during the study period. During the early period, similar event rates were found irrespective of the NHB uses. PAI-039 inhibitor During the late period, BB was associated with reduced HF readmission, and ACEi/ARB was associated with reduced HF readmission and gastrointestinal bleeding (p less then 0.05 for all). In conclusion, BB and ACEi/ARB use during the late period was associated with a reduction in HF recurrence in LVAD patients. Further prospective randomized control trials are warranted to clarify the utility of NHB therapy in LVAD patients.Continuous-flow left ventricular assist device (CF-LVAD) recipients exhibit impaired exercise capacity. Long-term continuous blood flow also elevates norepinephrine (NE) and aldosterone (Aldo) levels. However, the relationship between exercise capacity and neurohormonal activation has not been elucidated. Our study objective was to assess the association between cardiopulmonary exercise testing (CPT) measures and neurohormonal levels in CF-LVAD recipients. Symptom-limited CPT on a treadmill, using the modified Bruce protocol was performed in 15 CF-LVAD recipients. Norepinephrine and Aldo levels were measured, and the association between their levels and CPT measures were assessed. Peak VO2 (13.6 ml/kg/min) and percent age, sex predicted VO2 max (49.4%), and oxygen pulse (O2 pulse) (9.0 ± 4.0 ml/beat) were low, whereas minute ventilation/carbon dioxide output (VE/VCO2) slope (35) was elevated. In addition, VO2 at anaerobic threshold (VO2 AT), and O2 pulse values negatively correlated with NE levels. Norepinephrine levels positively correlated with chronotropic responses and heart rate (HR) recovery.
My Website: https://www.selleckchem.com/products/tiplaxtinin-pai-039.html