PURPOSE:Several studies have investigated the administration of vitamin C (vitC) for the prevention of postoperative atrial fibrillation (AF) after cardiac surgery. However, their findings were inconsistent. The purpose of this meta-analysis was to evaluate the efficacy of vitC as prophylaxis for the prevention of postoperative AF in cardiac surgery.METHODS:A systematic search of PubMed, EMBASE, Google Scholar, the Cochrane Library, and clinical trial registries, was performed. 9 studies, published from August 2001 to May 2015, were included, with a total of 1,037 patients. Patients were randomized to receive vitC, or placebo.RESULTS:Cardiac surgery patients who received vitC as prophylaxis, had a significantly lower incidence of postoperative AF (random effects OR=0.478, 95% CI 0.340 - 0.673, P < 10(-4)). No significant heterogeneity was detected across the analyzed studies (I(2)=21.7%), and no publication bias or other small study-related bias was found.CONCLUSION:Our findings suggest that VitC is effective as prophylaxis for the prevention of postoperative AF. The administration of vitC may be considered in all patients undergoing cardiac surgery.
Objectives: For patients with invasive breast cancer, management decisions are informed by tumor grade according to the Nottingham Grading System (NGS), either on its own or as part of the Nottingham Prognostic Index (NPI). A system retaining the nuclear grade element but substituting the two subjective components, mitosis count and tubule formation, of the NGS with a proliferation index based on Ki-67 (MIB-1) has been proposed (nuclear grade plus proliferation [N+P] grading).Methods: We validated the prognostic value of this grading system on a population of 322 women.Results: N+P grading resulted in more grade I tumors (47.9% vs 4.5%) and fewer grade II (32% vs 51.5%) and grade III (20.1% vs 44%) tumors compared with NGS. The NPI calculated based on N+P grade had a similar association with survival (P < .001; odds ratio, 1.729) as the NPI calculated on the basis of the NGS grade (P < .001; odds ratio, 1.668).Conclusions: The N+P system seems equivalent to the NGS system.
We review the role of endothelin (ET) A-receptors (R) on the coronary circulation. ET-1 maintains the normal coronary artery tone. ET-1 plasma levels are increased during and after coronary angioplasty and this increase is related to myocardial ischaemia rather than to mechanical artery injury. ETAR antagonists inhibit coronary artery vasoconstriction induced by ET release after coronary angioplasty in humans. ET promotes neointimal formation and ETAR antagonism has been shown to inhibit restenosis after angioplasty in the animal model but not in humans. ETAR blockade increases coronary blood flow, dilates distal coronary arterial segments and decreases coronary vascular resistance. Coronary collaterals are less sensitive than other coronary vessels to ET-1. ETAR blockade decreases collateral blood flow and, consequently, perfusion of the ischemic myocardium.
The association between myelodysplastic syndromes (MDS) and autoimmune manifestations is not uncommon. As a rule, autoimmune abnormalities follow the diagnosis of MDS. We describe here a patient with MDS who developed a striking spectrum of diverse autoimmune disorders, including dermatitis, polyarthritis, and vasculitis, which preceded the clinical appearance of MDS.
Cardiac disease is the primary cause of mortality in beta-thalassemia patients. Except for ventricular dysfunction and pulmonary hypertension that represent the main forms of heart disease in these patients, valvular abnormalities including valvular regurgitation, endocardial thickening and calcification and mitral valve prolapse have also been described. Here we present two patients with thalassemia major and mitral chordal rupture, a previously undescribed abnormality in this population. Pathogenesis of this finding may involve thalassemia-related pseudoxanthoma elasticum-like syndrome, a diffuse elastic tissue defect, which is observed with a notable frequency in these patients and has been associated with numerous cardiovascular complications, including valvular ones.
Infectious complications constitute the second most common cause of mortality and a main cause of morbidity in beta-thalassemia. Besides the high risk of blood-borne infections associated with multiple transfusions, the increased susceptibility of these patients to infectious diseases has been attributed to a coexistent immune deficiency. Immune abnormalities have also been held responsible for the frequent occurrence of malignancies in beta-thalassemia, especially leukemia and lymphomas. Recent studies on immune competence in beta-thalassemia have revealed numerous quantitative and functional defects, involving T and B lymphocytes, immunoglobulin production, neutrophils and macrophages, chemotaxis, and phagocytosis, as well as the complement system. Regarding pathogenesis, iron overload, a primary complication of both thalassemia itself and transfusion therapy, is thought to be the main precipitating mechanism, due to the important immunoregulatory properties of iron and its binding proteins; iron excess may derange the immune balance in favor of the growth of infectious organisms. Other factors include multiple transfusions, associated with constant allo-antigenic stimulation, as well as with transmission of immunosuppressive viruses; splenectomy, resulting in increased susceptibility to infections by encapsulated bacteria and to immune system modifications; low levels of zinc, another immune regulator; iron chelation therapy, which predisposes to serious infections by yersinia species; and the circulation of abnormal native thalassemic erythrocytes, forming another permanent immune stimulus. Thus surveillance for infections in patients with beta-thalassemia is crucial, while further studies are warranted on immune function abnormalities and the implicated mechanisms.
The coexistence of a pseudoxanthoma elasticum (PXE)-like syndrome in beta-thalassemia and other hemoglobinopathies is a recently established clinical entity that has been observed with a significant frequency and related to some severe, even life-threatening complications. We present here a thalassemia intermedia patient who developed unstable angina in a setting of severe anemia and PXE-related coronary arterial calcification. Besides the clinical significance of this PXE-like syndrome, its acquired nature may introduce some new thoughts regarding the pathogenesis of atherosclerosis.