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51.
Severe aortic insufficiency (AI) after implantation of continuous-flow left ventricular-assist device (LVAD) affects device performance and outcomes. However, the mechanism for the occurrence and progression of AI has not been elucidated. We investigated the impact of nonphysiological retrograde blood flow in the aortic root on AI after LVAD implantation. Blood flow pattern was analyzed in patients with and without AI (n = 3 each) who underwent LVAD implantation, by computational fluid dynamics with patient-specific geometries, which were reproduced using electrocardiogram-gated 320-slice computed tomographic images. The total volume of retrograde blood flow during one cardiac cycle (716 ± 88 mL) was higher and the volume of slow blood flow (<0.1 cm/s) (0.16 ± 0.04 cm3) was lower in patients with AI than in those without AI (360 ± 111 mL, P = .0495, and 0.49 ± 0.08 cm3, P = .0495, respectively). No significant difference in wall shear stress on the aortic valve was observed between the groups. Patients with AI had a perpendicular anastomosis at the distal ascending aorta and the simulation in the modified anastomosis model of patients with AI showed that the retrograde blood flow pattern depended on the angle and position of anastomosis. Computational fluid dynamics revealed strong retrograde blood flow in the ascending aorta and aortic root in patients with AI after LVAD implantation. The angle and position of LVAD outflow anastomosis might impact retrograde blood flow and de novo AI after LVAD implantation.  相似文献   
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World Journal of Surgery - Gastric cancers located within the upper-third of the stomach (UGC), especially the esophagogastric junction GC (EGJGC), have distinct clinicopathological features due to...  相似文献   
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Surgery Today - Postoperative spinal cord injury is a devastating complication after aortic arch replacement. The purpose of this study was to determine the predictors of this complication. A group...  相似文献   
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Resected bile duct cancers often relapse during postoperative follow-up. The aim of this study was to detect predictors of early recurrence in patients with extrahepatic bile duct cancer. Consecutive cases (n = 162) of extrahepatic bile duct cancer in which R0 or R1 resection was achieved in Kobe University Hospital between 2000 and 2016 were divided into three groups [early recurrence (ER), within 6 months of surgery, late recurrence (LR), and no recurrence (NR)] and their clinicopathological features were compared. Twenty-two patients (14%) developed ER and 69 (43%) developed LR after surgery. The rates of lymph node metastasis and residual cancer status were similar in all three groups. Liver metastasis was more common in the ER group than in the LR group (59% vs. 32%, p = 0.02). ER had a significantly worse prognosis than LR and NR (7% vs. 44% vs. 85% at 1 year, p < 0.01, respectively). Multivariate analysis showed that age > 75 years, serum CA19-9 > 1008 U/ml and perineural invasion were independent predictors of early recurrence. High serum CA19-9 values (> 1008 U/ml) were an independent predictor of early recurrence. Neoadjuvant therapy and aggressive adjuvant therapy may be beneficial for patients who show highly elevated CA19-9 values before surgery.  相似文献   
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Arteriovenous access ischaemic steal is a serious complication following arteriovenous fistula (AVF) construction. The aim of treatment is to improve distal circulation without impairing the function of the fistula. Therefore, any repair should be performed with intraoperative monitoring. We report 2 cases of this disorder treated using perioperative measurement of skin perfusion pressure (SPP) for preoperative surgical planning and intraoperative guidance. A 73‐year‐old woman with a left cubital AVF developed gangrene of the tip of the left little finger. Arteriovenous access ischaemic steal was suspected. The SPP of the little finger was 18 mm Hg, which increased to 65 mm Hg after manual occlusion of the fistula. A 58‐year‐old woman with a left antebrachial AVF had gangrene of the tip of the left middle finger. The SPP was 19 mm Hg, and steal syndrome was suspected based on angiography and the SPP with manual occlusion of the fistula. In both cases, serial plication of the fistula was performed based on intraoperative perfusion pressure monitoring, leading to the successful resolution of the ischaemic steal syndrome. In both cases, haemodialysis could be continued through the repaired fistula.  相似文献   
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