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1.
Coronavirus disease 2019 (COVID-19) has resulted in many challenges in patient care, especially among high-risk populations such as heart transplant recipients. Patients with heart transplant experience a significantly higher mortality rate with COVID-19 infection, and management is based on extrapolation from clinical trials done on nontransplant patients and from clinical experience. Here we report 4 cases of patients with heart transplant who presented with COVID-19 infection in late 2020. Patients presented with symptoms similar to those seen in the general population. All 4 patients were admitted to the hospital, and they were all treated with dexamethasone. In addition, 2 patients received remdesivir. Immunosuppressive medications were adjusted to maintain adequate levels of immunosuppression but at the same time allow for an adequate immune response against the infection. All patients were discharged alive from the hospital. We then performed a literature review on studies that included heart transplant patients who developed the infection and developed suggestions for a standardized management approach, which we share in this article.  相似文献   
2.

Objective

Low psoas muscle area is shown to be an indicator for worse postoperative outcome in patients undergoing vascular surgical. Additionally, it has been associated with longer durations of hospital stay in patients with cancer who undergo surgery and subsequently greater health care costs in Europe and the United States. We sought to evaluate this effect on hospital expenditure for patients undergoing vascular repair in a health care system with universal access.

Methods

Skeletal muscle mass was assessed on preoperative abdominal computed tomography scans of patients undergoing open aortic aneurysm repair in a retrospective fashion. The skeletal muscle index (SMI) was used to define low muscle mass. Health care costs were obtained for all patients and the relationship between a low SMI and higher costs was explored using linear regression and cross-sectional analysis.

Results

We included 156 patients (81.5% male) with a median age of 72 years undergoing elective surgery for infrarenal abdominal aortic aneurysm in this analysis. The median SMI for patients with low skeletal muscle mass was 53.21 cm2/kg and for patients without, 70.07 cm2/kg. Hospital duration of stay was 2 days longer in patients with low skeletal muscle mass as compared with patients with normal (14 days vs 11 days; P = .001), as was duration of intensive care stay (3 days vs 1 day; P = .01). The median overall hospital costs were €10,460 higher for patients with a low SMI as compared with patients with a normal physical constitution (€53,739 [interquartile range, €45,007-€62,471] vs €43,279 [interquartile range, €39,509-€47,049]; P = .001). After confounder adjustment, a low SMI was associated with a 14.68% cost increase in overall hospital costs, for a cost increase of €6521.

Conclusions

Low skeletal muscle mass is independently associated with higher hospital as well as intensive care costs in patients undergoing elective aortic aneurysm repair. Strategies to reduce this risk factor are warranted for these patients.  相似文献   
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Background Despite improving surgical techniques, treatment of heart valve disease in children remains controversial. Somatic growth and adequate anticoagulation are of concern when children undergo valve replacement. We conducted this study to evaluate the performance of valves in this age group. Methods 42 children under the age of 13 years who underwent valve replacement were included in this study. Totally, 50 valves were implanted in 42 patients: 48 were mechanical prostheses, two were bioprosthetic both in pulmonary position. 37 (74%) valves were implanted in mitral position, 10 (20%) in aortic position, 1 (2%) in tricuspid position and 2 (4%) in pulmonary position. Preoperatively, 14 (33,3%) patients were in New York Heart Association (NYHA) class IV, while 27 (64.2%) were in NYHA class III. Results There were 2 (4.7%) hospital deaths and 2 (4.7%) late deaths while 2 (4.7%) patients were lost to follow up. The mean follow up period was 9.4 yrs. 35 (83.3%) patients are in NYHA Class I and free of all medications except warfarin. 3 (7.1%) patients have undergone 5 successful pregnancies. The median INR was 2.23. Major thrombo-embolic episode occurred in 1 (2.3%) patient. Conclusions In view of the problems of sizing, anticoagulation and need for re-operation at an early age, there is a reluctance to replace valves in children. This study shows that despite these problems, valve replacement can be undertaken safely and successfully in children, when repair has failed or not technically feasible.  相似文献   
5.
6.
BACKGROUND: Pre-clinical and clinical studies suggest that transplantation of bone marrow-derived stem cells can improve global cardiac function. However, no quantitative assessment of regional systolic contraction and correlation with phenotype has been made. Therefore, we used our model of cryoinfarcted rabbit myocardium for intracardiac transplantation of a mixed population of bone marrow-derived cells and assessed both regional function and myogenic conversion of the cells. METHODS: Nineteen New Zealand white rabbits underwent cryoinjury of the left ventricle. Autologous bone marrow (BM) cells were expanded in vitro. After 2 weeks, either 1 x 10(8) mixed BM-derived progenitor cells (BM group, n = 11) or vehicle (control group, n = 8) were injected into the cryoinjured region. Regional systolic function was measured using micromanometry and sonomicrometry before and 4 weeks after cell injection; cell phenotype was evaluated histologically. RESULTS: All animals in the BM group significantly improved both systolic shortening (0.11 +/- 0.7 vs -0.05 +/- 0.05 mm in the control group, p < 0.05) and regional stroke work when compared with control (9.6 +/- 2.4 vs -1.2 +/- 1.2 mm . mm Hg, p < 0.003). In addition, the BM group had improved global diastolic function, as measured by minimum dP/dt and end-diastolic pressure. On histologic assessment, BM cells differentiated toward a myogenic phenotype. CONCLUSIONS: Transplanting a mixed population of marrow-derived cells that can adopt a myogenic phenotype improves regional contractility and diastolic relaxation after myocardial infarction.  相似文献   
7.
8.
Platelets are cell fragments with dynamic properties involved in clot formation after tissue damage. Platelet activation causes a change in shape, secretion of intracellular granules and aggregation with each other through the cytoskeleton components and biochemical changes. Platelet adhesion, considered as the major event in haemostasis, has been studied in several in-vitro and in-vivo models to evaluate the feasible thrombogenicity of some materials, the dynamics of specific receptors, as well as the effect of different buffers and inhibitors in this process. In spite of the numerous reports about platelet activation, to date there is no information available about the fine structure of the platelet-platelet and platelet-substrate interactions. In the present report we describe an in-vitro system that allows the visualization of these interactions: platelets are adhered to an inert substrate, and interactions with suspended platelets as a process to initiate the formation of thrombi was followed by ultramicrotomy and transmission electron microscopy.  相似文献   
9.
Summary: The effect of gestational age on neonatal ictal and interictal durations has not been investigated. Sixty-eight neonates with 644 electrographic seizures were identified retrospectively. Thirty-five full-term (FT) neonates were compared with 33 preterm (PT) neonates. Eighteen older preterm infants (OPT) [>31 weeks estimated gestational age (EGA)] were also compared with 15 young preterm infants (YPT) of ≤31 weeks EGA. Ictal/ interictal durations were calculated for the total cohort with and without status epilepticus (SE). Statistical analyses were two-tailed t tests, chi-square calculations, and one-way analysis of variance (ANOVA) with Duncan's multiple-range test. Eleven of 35 (33%) FT had SE as compared with 3 of 33 (9%) PT (chi-square = 7.8, p < 0.05). The mean ictal duration was 14.2 min for FT infants as compared with 3.1 min for PT infants (p < 0.01); only borderline differences were noted after those with SE were excluded. Interictal durations were longer for OPT than YPT (p < 0.05). By ANOVA and Duncan's multiple-range tests, group differences included longer mean ictal durations for FT infants as compared with OPT infants (p = 0.06, ANOVA; p < 0.05, Duncan's), and longer mean interictal durations for FT infants versus OPT and OPT versus YPT (p = 0.02, ANOVA; p < 0.05, Duncan's). More developed neuronal networks result in longer ictal durations in FT than in PT neonates, including FT infants with SE. Inhibitory networks responsible for longer interictal periods are more dominant in OPT infants than in YPT infants, reflecting maturational changes that suppress seizure activity during the latter part of the third trimester before the infant reaches an FT corrected age.  相似文献   
10.
AIMS: To evaluate the efficacy of culture, histology, CLO-test, Helico-G and Pyloriset tests in diagnosing Helicobacter pylori in the presence or absence of non-steroidal anti-inflammatory drugs (NSAIDs). METHODS: Of 134 patients studied, 75 had taken NSAIDs. At endoscopy, biopsy specimens were taken for culture, histology, and CLO-test. Blood was also taken for enzyme linked immunosorbent assay (ELISA) (Helico-G) and latex agglutination (Pyloriset) tests. RESULTS: The sensitivity, specificity, and predictive values of histology and CLO-test, compared with culture, ranged from 90% to 97%, regardless of NSAID intake. In the 59 patients not taking NSAIDs Helico-G had a sensitivity of 75% (p < 0.05) and a specificity of 61%; Pyloriset's sensitivity and specificity were, respectively, 63% (p < 0.05) and 67%. In the 75 patients taking NSAIDs the sensitivity of Helico-G was 81% and its specificity 45% (p < 0.05); Pyloriset had a sensitivity of 61% (p < 0.05) and a specificity of 50% (p < 0.05). CONCLUSION: These findings suggest that H pylori is more reliably diagnosed by culture, histology, and CLO-test than by the serological tests used in this study, especially in patients treated with NSAIDs.  相似文献   
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