Prophylactic-dose direct oral anticoagulants for non-hospitalised people with COVID-19: A meta-analysis of randomised controlled trials.

Background: Several reviews have been conducted on thromboprophylaxis in non-hospitalised patients with coronavirus disease 2019 (COVID-19). In this systematic review and meta-analysis, we sought to investigate the impact of prophylactic-dose direct oral anticoagulants (DOACs) in this population. Methods: We searched PubMed, Web of Science, EMBASE and Cochrane Library for randomised controlled trials (RCTs) comparing prophylactic-dose DOACs with placebo or no treatment in non-hospitalised patients with COVID-19 until September 2023. The primary efficacy outcome was a composite of all-cause mortality and thromboembolic events, while major bleeding events were the primary safety outcome. We expressed continuous outcome data as mean differences (MDs) with 95% confidence intervals (CIs) and dichotomous outcome data as risk ratios (RRs) with 95% CIs. Results: We included six RCTs involving 4307 patients. Prophylactic-dose DOAC therapy compared with placebo or no treatment was associated with significantly decreased risks of the composite outcome of all-cause mortality and thromboembolic events (1.43% vs 2.67% (RR = 0.53; 95% CI = 0.34-0.82, P = 0.004, I2 = 3%)). Major bleeding events were infrequent, and we detected no significant differences between patients assigned to prophylactic-dose DOACs vs placebo or no treatment (0.19% vs 0.05% (RR = 2.50; 95% CI = 0.49-12.87, P = 0.27, I2 = 0%)). The use of prophylactic-dose DOACs was also associated with a reduction in venous thromboembolism, with no difference in all-cause mortality, arterial thromboembolism, hospitalisations, and clinically relevant nonmajor bleeding between two groups. Sensitivity analyses with the leave-one-out method for the primary efficacy and safety outcome did not change the effect estimate substantially. Conclusions: We found that prophylaxis-dose DOACs could significantly improve clinical outcomes and reduce venous thrombotic events without increasing the risk of major bleeding events compared with placebo or no treatment in non-hospitalised patients with COVID-19. Registration: PROSPERO: CRD42023466889.

Coronary Microvascular Dysfunction and Diffuse Myocardial Fibrosis in Patients With Type 2 Diabetes Using Quantitative Perfusion MRI.

BACKGROUND: Imaging techniques that quantitatively and automatically measure changes in the myocardial microcirculation in patients with diabetes are lacking. PURPOSE: To detect diabetic myocardial microvascular complications using a novel automatic quantitative perfusion MRI technique, and to explore the relationship between myocardial microcirculation dysfunction and fibrosis. STUDY TYPE: Prospective. SUBJECTS: 101 patients with type 2 diabetes mellitus (T2DM) (53 without and 48 with complications), 20 healthy volunteers. FIELD STRENGTH/SEQUENCE: 3.0T; modified Look-Locker inversion-recovery sequence; saturation recovery sequence and dual-bolus technique; segmented fast low-angle shot sequence. ASSESSMENT: All participants underwent MRI to determine the rest myocardial blood flow (MBF), stress MBF, myocardial perfusion reserve (MPR), and extracellular volume (ECV), which represents the extent of myocardial fibrosis. STATISTICAL TESTS: Kolmogorov-Smirnov test, Shapiro-Wilk test, Kruskal-Wallis H test, Mann-Whitney U test, chi-square test, Spearman correlation coefficient, multivariable linear regression analysis. P < 0.05 was considered statistically significant. RESULTS: The rest MBF was not significantly different between the T2DM without complications group (1.1, IQR: 0.9-1.3) and the control group (1.1, 1.0-1.3) (P = 1.000), but it was significantly lower in the T2DM with complications group (0.8, 0.6-1.0) than in both other groups. The stress MBF and MPR were significantly lower in the T2DM without complications group (1.9, 1.5-2.3, and 1.7, 1.4-2.1, respectively) than in the control group (3.0, 2.6-3.5, and 2.7, 2.4-3.1, respectively), and were also significantly lower in the T2DM with complications group (1.1, 0.9-1.4, and 1.4, 1.2-1.8, respectively) than in the T2DM without complications group. A decrease in MBF and MPR were significantly associated with an increase in the ECV. DATA CONCLUSION: Quantitative perfusion MRI can evaluate myocardial microcirculation dysfunction. In T2DM, there was a significant decrease in both MBF and MPR compared to healthy controls, with the decrease being significantly different between T2DM with and without complications groups. The decrease of MBF was significantly associated with the development of myocardial fibrosis, as determined by ECV. LEVEL OF EVIDENCE: 2 TECHNICAL EFFICACY: Stage 3.

Case report: A primary calcified cardiac mass in right atrium partially obstructs the tricuspid valve in a patient on hemodialysis.

Primary cardiac calcification is a rare benign mass in patients with end-stage renal disease. A few cases have been reported in the literatures. In this case study, during a routine checkup for hemodialysis, a transthoracic echocardiography on a 19-year-old male showed a cardiac mass in the right atrium that was partially obstructing the tricuspid valve. Cardiac magnetic resonance imaging showed a well-circumscribed, homogeneous "shadow" in the right atrium; it measured 29 × 27 mm, had equal T1- and T2-weighted signal intensities, and was adjacent to the tricuspid valve. According to 18F-fluorodeoxyglucose positron emission tomography combined with computed tomography, there was a dense circular shadow in the right atrium abutting the tricuspid valve, but there was no increase in glucose metabolism. Median sternotomy was performed for the surgical resection of the mass, and a cardiopulmonary bypass was completed. The mass was completely removed. The patient recovered well and was discharged 10 days after the surgery. Histological examination showed that the mass contained multiple calcified nodules. No mass recurrence was found by echocardiography during the 12th-month follow-up.

Removal of sewing needles from interventricular septum under the guidance of multiple imaging modalities.

BACKGROUND: Penetration of the interventricular septum (IVS) by a sharp foreign body is a rare and potentially life-threatening event. METHODS: We present the case of a 43-year-old female who had thrust four embroidery needles into her left chest wall while experiencing hallucinations after using an illegal drug. One needle had penetrated the heart and was embedded in the IVS, as confirmed by intraoperative transesophageal echocardiography (TEE), and one needle had lodged in the left chest wall. RESULTS: The sewing needles penetrating the IVS and chest wall were successfully removed under the guidance of TEE and a cardiopulmonary bypass without cross-clamping the aorta or opening the heart. CONCLUSION: The sewing needles embedded in the IVS and left chest wall were successfully removed with the aid of multiple imaging modalities.

Case Report: A Primary Right Ventricular Vascular Malformation Presenting as a Mass.

Primary right ventricular vascular malformation is a rare primary benign anomaly in heart in nature. Due to the extremely low incidence and the progress on the classification of vascular malformation, a few cases were reported in the literatures. In the current case study, a 55-year-old women presented with a cardiac mass that was identified in right ventricle during a routine medical checkup. Magnetic resonance imaging demonstrated a well-circumscribed mass attached to the interventricular septum. Median sternotomy for the surgical resection of the mass and a cardiopulmonary bypass were performed. The intraoperative transesophageal echocardiogram showed that the mass had been successfully removed. The patient recovered well and was discharged from hospital 9 days after the surgery. The pathological diagnosis was primary cardiac arteriovenous malformation. No mass recurrence was shown by echocardiography during the 13 months' follow-up.

Case Report: The Cox-Maze IV Procedure in the Mirror: The Use of Three-Dimensional Printing for Pre-operative Planning in a Patient With Situs Inversus Dextrocardia.

The safety and efficacy of the Cox-Maze IV procedure (CMP-IV) for situs inversus dextrocardia patients with atrial fibrillation is yet to be determined. Herein, we present the case of a 39-year-old male patient admitted to our cardiac center following progressive exertional dyspnea. The patient was diagnosed with situs inversus dextrocardia, severe mitral regurgitation, and paroxysmal atrial fibrillation. A three-dimensional (3D) heart model printing device embedded with designated ablation lines was used for pre-operative planning. Mitral valvuloplasty, CMP-IV, and tricuspid annuloplasty were performed. The patient had an uneventful recovery and was in sinus rhythm during a 12-month follow-up period using a 24-h Holter monitoring device. The case herein is one of the first to report on adopting the CMP-IV procedure for situs inversus dextrocardia patients with complex valvuloplasty operation. In addition, the 3D printing technique enabled us to practice the Cox-maze IV procedure, given the patient's unique cardiac anatomy.

[EFFECT OF Akt1 GENE TRANSFECTION ON HYPOXIA TOLERANCE OF BONE MARROW MESENCHYMAL STEM CELLS].

OBJECTIVE: To investigate whether Akt1 gene transfection mediated by recombinant lentivirus (LVs) in the bone marrow mesenchymal stem cells (BMSCs) could enhance the ability of hypoxia tolerance so as to provide a theoretical basis for improving the effectiveness of stem cells transplantation. METHODS: LVs was used as transfection vector, enhanced green fluorescent protein (EGFP) was used as markers to construct the pLVX-EGFP-3FLAG virus vector carrying the Akt1 gene. The 3rd generation BMSCs from 3-5 weeks old Sprague Dawley rats were transfected with pLVX-EGFP virus solution as group B and with pLVX-EGFP-3PLAG virus solution as group C; and untransfected BMSCs served as control group (group A). At 2-3 days after transfection, the expression of green fluorescent was observed by fluorescence microscope; and at 48 hours after transfection, Western blot method was used to detect the expression of Akt1 protein in groups B and C. BMSCs of groups B and C were given hypoxia intervention with 94% N2, 1% O2, and 5% CO2 for 0, 3, 6, 9, and 12 hours (group B1 and group C1). The flow cytometry was used to analyze the cell apoptosis rate and cell death rate, and the MTT method to analyze the cell proliferation, and Western blot to detect the expression of apoptosis related gene Caspase-3. RESULTS: After transfection, obvious green fluorescence was observed in BMSCs under fluorescence microscopy in groups B and C, the transfection efficiency was about 60%. Akt1 expression of group C was significantly higher than that of group B (t = 17.525, P = 0.013). The apoptosis rate and cell death rate of group B1 increased gradually with time, and difference was significant (P < 0.05). In group C1, the apoptosis rate and cell death rate decreased temporarily at 3 hours after hypoxia intervention, then increased gradually, and difference was significant (P < 0.05). The apoptosis rate and cell death rate of group C1 were significantly lower than those of group B1 at each time point (P < 0.05) except at 0 hour. MTT assay showed tat absorbance (A) values of groups B and C were significantly higher than those of groups B1 and C1 at each time point (P < 0.05); the A value of group B was significantly lower than that of group C at each time point (P < 0.05). The A value of group B1 was significantly lower than that of group Cl at 6, 9, and 12 hours after hypoxia intervention (P < 0.05). Western blot results showed that the Caspase-3 expression of group C1 significantly reduced when compared with group B1 at each time point (P < 0.05). CONCLUSION: Akt1 gene transfection mediated by recombinant LVs could significantly improve hypoxia tolerance of BMSCs by inhibiting the apoptosis, which could provide new ideas for improving the effectiveness of stem cells transplantation.

Shear stress regulates endothelial cell function through SRB1-eNOS signaling pathway.

AIM: The aim of this study was to explore whether transmembrane flow shear stress could regulate eNOS expression and mediate endothelial cell function via SR-B1 signaling transduction. METHODS: Parallel-plate flow chamber was used to impose laminar shear stress and evaluate the effect of shear stress upon human umbilical vein endothelial cells (HUVECs). The expression of SR-B1 and eNOS at both RNA and protein levels was detected under different dynamic conditions. RNA interference and gene transfection were performed to overexpress and knock down the SRB1 to confirm the role of SR-B1-eNOS signaling pathway. RESULTS: The expression levels of SR-B1 and eNOS were downregulated when HUVECs were treated with 4.2 dyne/cm(2) shear stress compared with those of the control group. However, the expression of SR-B1 and eNOS was upregulated as HUVECs exposed to 8.4 and 15 dyne/cm(2) shear stress. When exposed to 8.4 dyne/cm(2) , SR-B1 and eNOS expression was significantly higher compared with those of the other groups. When SR-B1 was knocked down through RNAi technique, the expression of eNOS was significantly downregulated than those of the other groups. While overexpression of SR-B1 could upregulate eNOS significantly. CONCLUSION: Shear stress regulates endothelial cell function through SR-B1-eNOS signaling pathway. SR-B1 may play a pivotal role in the process of anti-atherosclerosis.