Lifestyle physical activity and rapid-rate non-sustained ventricular tachycardia in arrhythmogenic cardiomyopathy.

OBJECTIVE: To investigate the association of accelerometer-measured lifestyle physical activity with rapid-rate non-sustained ventricular tachycardias (RR-NSVTs) in patients with arrhythmogenic cardiomyopathy (AC). METHODS: This multicentre, observational study enrolled 72 patients with AC, including right, left and biventricular forms of the disease, with underlying desmosomal and non-desmosomal mutations. Lifestyle physical activity, objectively monitored with accelerometers (ie, movement sensors) and RR-NSVT, identified as >188 bpm and >18 beats from a textile Holter ECG for 30 days. RESULTS: Sixty-three patients with AC (38±17.6 years, 57% men) were included. A total of 17 patients experienced ≥1 RR-NSVTs, and a total of 35 events were recorded. The odds of occurrence of ≥1 RR-NSVT during the recording did not increase as a function of either total physical activity (OR 0.95, 95% CI (CI95%) 0.68 to 1.30 for 60 min increase) or moderate-to-vigorous activities (OR 0.89, CI95% 0.71 to 1.08 for 5 min increase). Participants presenting RR-NSVTs during the recording (n=17) did not present greater odds of RR-NSVT in the days with more time either in total physical activity (OR 1.05, CI95% 0.84 to 1.29 for additional 60 min) or moderate-to-vigorous activities (OR 1.05, CI95% 0.97 to 1.12 for additional 5 min). Physical activity levels were neither different between the patients with and without RR-NSVTs during the recording period nor in the days of occurrence of RR-NSVT compared with the rest of the days. Finally, 4 of the 35 RR-NSVTs recorded in the 30 days occurred during physical activity (3 during moderate-to-vigorous intensity and 1 during light-intensity activities). CONCLUSIONS: These findings suggest that lifestyle physical activity is not associated with RR-NSVTs in patients with AC.

Prevalence of bleeding secondary to anticoagulation and mortality in patients with atrial fibrillation admitted with SARS-CoV-2 infection.

Introduction and purpose: Atrial fibrillation (AF) is common in patients admitted with severe COVID-19. However, there is limited data about the management of chronic anticoagulation therapy in these patients. We assessed the anticoagulation and incidence of major cardiovascular events in hospitalized patients with AF and COVID-19. Methods: We retrospectively investigated all consecutive patients with AF admitted with COVID-19 between March and May 2020 in 9 Spanish hospitals. We selected a control group of non-AF patients consecutively admitted with COVID-19. We compared baseline characteristics, incidence of major bleeding, thrombotic events and mortality. We used propensity score matching (PSM) to minimize potential confounding variables, as well as a multivariate analysis to predict major bleeding and death. Results: 305 patients admitted with AF and COVID-19 were included. After PSM, 151 AF patients were matched with 151 control group patients. During admission, low-molecular-weight heparin was the principal anticoagulant and the incidence of major bleeding and mortality were higher in the AF group [16 (10.6%) vs 3 (2%), p = 0.003; 52 (34.4%) vs 35 (23.2%), p = 0.03, respectively]. The multivariate analysis showed the presence of AF as independent predictor of in-hospital major bleeding and mortality in COVID-19 patients. In AF group, a secondary multivariate analysis identified high levels of D-dimer as independent predictor of in-hospital major bleeding. Conclusions: AF patients admitted with COVID-19 represent a population at high risk for bleeding and mortality during admission. It seems advisable to individualize anticoagulation therapy during admission, considering patient specific bleeding and thrombotic risk.

Antecedentes y objetivos: La fibrilación auricular (FA) es frecuente en pacientes ingresados por COVID-19 grave. Sin embargo, los datos sobre el manejo de la anticoagulación crónica en estos pacientes son escasos. Analizamos la anticoagulación y la incidencia de episodios cardiovasculares mayores en pacientes con FA ingresados por la COVID-19. Métodos: Retrospectivamente, se identificaron todos los pacientes con FA ingresados por la COVID-19 entre marzo y mayo de 2020, en 9 hospitales españoles. Se seleccionó un grupo control de pacientes ingresados consecutivamente por la COVID-19 sin FA. Se compararon las características basales, incidencia de hemorragias mayores, episodios trombóticos y mortalidad. Para reducir potenciales factores de confusión se realizó un emparejamiento por puntuación de propensión, así como un análisis multivariante para predecir hemorragia mayor y mortalidad. Resultados: Se incluyeron 305 pacientes con FA ingresados por la COVID-19. Tras el emparejamiento por puntuación de propensión, 151 pacientes con FA fueron emparejados con 151 controles. Durante el ingreso, la heparina de bajo peso molecular fue el principal anticoagulante y la incidencia de hemorragia mayor y mortalidad fue mayor en el grupo de FA (16[10,6%] vs. 3[2%], p = 0,003; 52[34,4%] vs. 35[23,2%], p = 0,03, respectivamente). El análisis multivariante demostró la presencia de FA como predictor independiente de sangrados y mortalidad intrahospitalaria en los pacientes con la COVID-19. En el grupo de FA, un segundo análisis multivariante identificó valores elevados de dímero-D como predictor independiente de hemorragia mayor intrahospitalaria. Conclusiones: Los pacientes con FA ingresados por la COVID-19 representan una población de alto riesgo de sangrado y mortalidad durante el ingreso. Parece recomendable individualizar la anticoagulación durante el ingreso, considerando el riesgo específico de sangrado y trombosis.

Prevalence of bleeding secondary to anticoagulation and mortality in patients with atrial fibrillation admitted with SARS-CoV-2 infection.

INTRODUCTION AND PURPOSE: Atrial fibrillation (AF) is common in patients admitted with severe COVID-19. However, there is limited data about the management of chronic anticoagulation therapy in these patients. We assessed the anticoagulation and incidence of major cardiovascular events in hospitalized patients with AF and COVID-19. METHODS: We retrospectively investigated all consecutive patients with AF admitted with COVID-19 between March and May 2020 in 9 Spanish hospitals. We selected a control group of non-AF patients consecutively admitted with COVID-19. We compared baseline characteristics, incidence of major bleeding, thrombotic events and mortality. We used propensity score matching (PSM) to minimize potential confounding variables, as well as a multivariate analysis to predict major bleeding and death. RESULTS: 305 patients admitted with AF and COVID-19 were included. After PSM, 151 AF patients were matched with 151 control group patients. During admission, low-molecular-weight heparin was the principal anticoagulant and the incidence of major bleeding and mortality were higher in the AF group [16 (10.6%) vs 3 (2%), p=0.003; 52 (34.4%) vs 35 (23.2%), p=0.03, respectively]. The multivariate analysis showed the presence of AF as independent predictor of in-hospital major bleeding and mortality in COVID-19 patients. In AF group, a secondary multivariate analysis identified high levels of D-dimer as independent predictor of in-hospital major bleeding. CONCLUSIONS: AF patients admitted with COVID-19 represent a population at high risk for bleeding and mortality during admission. It seems advisable to individualize anticoagulation therapy during admission, considering patient specific bleeding and thrombotic risk.

Heterozygous Arrhythmogenic Cardiomyopathy-desmoplakin Mutation Carriers Exhibit a Subclinical Cutaneous Phenotype with Cell Membrane Disruption and Lack of Intercellular Adhesion.

Genetic variants that result in truncation in desmoplakin (DSP) are a known cause of arrhythmogenic cardiomyopathy (AC). In homozygous carriers, the combined involvement of skin and heart muscle is well defined, however, this is not the case in heterozygous carriers. The aim of this work is to describe cutaneous findings and analyze the molecular and ultrastructural cutaneous changes in this group of patients. Four women and eight men with a mean age of 48 ± 14 years were included. Eight met definitive criteria for AC, one was borderline and three were silent carriers. No relevant macroscopic changes in skin and hair were detected. However, significantly lower skin temperature (29.56 vs. 30.97 °C, p = 0.036) and higher transepidermal water loss (TEWL) (37.62 vs. 23.95 g m 2 h 1, p = 0.028) were observed compared to sex- and age-matched controls. Histopathology of the skin biopsy showed widening of intercellular spaces and acantholysis of keratinocytes in the spinous layer. Immunohistochemistry showed a strongly reduced expression of DSP in all samples. Trichogram showed regular nodules (thickening) compatible with pseudomonilethrix. Therefore, regardless of cardiac involvement, heterozygous patients with truncation-type variants in DSP have lower skin temperature and higher TEWL, constant microscopic skin involvement with specific patterns and pseudomonilethrix in the trichogram.

Fraxetin prevents rotenone-induced apoptosis by induction of endogenous glutathione in human neuroblastoma cells.

Fraxetin belongs to an extensive group of natural phenolic anti-oxidants. In the present study, using a human neuroblastoma SH-SY5Y cells, we have investigated the protective effects of this compound on modifications in endogenous reduced glutathione (GSH), intracellular oxygen species (ROS) and apoptotic death on rotenone-mediated cytoxicity. Incubation of cells with the fraxetin led to a significant elevation dose-dependent of cellular GSH and this was accompanied by a marked protection against rotenone-mediated toxicity, which was also significantly reversed in the cells with buthionine sulfoximine (BSO) co-treatment. Taken together, this study suggested that intracellular GSH appeared to be an important factor in fraxetin-mediated cytoprotection against rotenone-toxicity in SH-SY5Y cells. Fraxetin at 10-100 muM inhibited the formation of ROS, cytochrome c release, activation of caspase-3 and 9, and suppressed the up-regulation of Bax, whereas no significant change occurred in Bcl-2 levels. Our results indicated that the anti-oxidative and anti-apoptotic properties render this natural compound potentially protective against rotenone-induced cytotoxicity.

Effect of fraxetin on antioxidant defense and stress proteins in human neuroblastoma cell model of rotenone neurotoxicity. Comparative study with myricetin and N-acetylcysteine.

Mitochondrial complex I inhibitor rotenone induces apoptosis through enhancing mitochondrial reactive oxygen species production. Recently, it has been shown that fraxetin (coumarin) and myricetin (flavonoid) have significant neuroprotective effects against apoptosis induced by rotenone, increase the total glutathione levels in vitro, and inhibit lipid peroxidation. Thus, these considerations prompted us to investigate the way in which fraxetin and myricetin affect the endogenous antioxidant defense system, such as Mn and CuZn superoxide dismutase (MnSOD, CuZnSOD), catalase, glutathione reductase (GR), and glutathione peroxidase (GPx) on rotenone neurotoxicity in neuroblastoma cells. N-acetylcysteine (NAC), a potent antioxidant, was employed as a comparative agent. Also, the expression and protein levels of HSP70 by Northern and Western blot analysis were assayed in SH-SY5Y cells. After incubation for 16 h, rotenone significantly increased the expression and activity of MnSOD, GPx, and catalase. When cells were preincubated with fraxetin, there was a decrease in the protein levels and activity of both MnSOD and catalase, in comparison with the rotenone treatment. The myricetin effect was less pronounced. Activity and expression of GPx were increased by rotenone and pre-treatment with fraxetin did not modify significantly these levels. The significant enhancement in HSP70 expression at mRNA and protein levels induced by fraxetin was observed by pre-treatment of cells 0.5 h before rotenone insult. These data suggest that major features of rotenone-induced neurotoxicity are partially mediated by free radical formation and oxidative stress, and that fraxetin partially protects against rotenone toxicity affecting the main protection system of the cells against oxidative injury.

Neuroprotective effect of fraxetin and myricetin against rotenone-induced apoptosis in neuroblastoma cells.

Rotenone-induced apoptosis is considered to contribute to the etiology of Parkinson's disease (PD). We try to prevent the apoptosis induced by rotenone toxicity with 50 microM myricetin, 100 microM fraxetin and 100 microM N-acetylcysteine (NAC) that protect against reactive oxygen species (ROS), on SH-SY5Y human neuroblastoma cell line. Morphological changes induced by rotenone and intracellular ROS were assessed in live SH-SY5Y dopaminergic cells by confocal microscopy using the fluorescent dyes, dihydroethidium and 2',7'-dichlorofluorescein diacetate (DCFH-DA). DNA fragmentation was assayed as index of apoptosis. We also investigated oxidative stress parameters such as the glutathione redox status and lipid peroxidation. The exposure of the SH-SY5Y cells to rotenone 5 microM for 16 h produced severe morphological changes, DNA fragmentation and significative increases in the levels of hydrogen peroxide and superoxide anion. These increases were reduced by a 30-min pretreatment with fraxetin 100 microM or NAC 100 microM. DNA laddering produced by rotenone treatment was also inhibited by fraxetin and NAC. Treatment with 5 microM rotenone induced loss of reduced glutathione (GSH) and increased cellular levels of oxidized glutathione (GSSG). Fraxetin and NAC treatments restored glutathione redox ratio diminished after rotenone challenge and decreased the levels of lipid peroxidation. These results suggest that the natural antioxidants, such as fraxetin, may prevent the apoptotic death of dopaminergic cells induced by rotenone and mediated by oxidative stress.