RESUMEN
OBJECTIVES: Skeletal muscle wasting, also known as sarcopenia, has recently been identified as a serious comorbidity in patients with heart failure (HF). We aimed to assess the impact of sarcopenia on endothelial dysfunction in patients with HF with reduced ejection fraction (HFrEF) and with preserved ejection fraction (HFpEF). DESIGN: Cross-sectional study. SETTING: Ambulatory patients with HF were recruited at Charité Medical School, Campus Virchow-Klinikum, Berlin, Germany. PARTICIPANTS: We assessed peripheral blood flow (arm and leg) in 228 patients with HF and 32 controls who participated in the Studies Investigating Comorbidities Aggravating HF (SICA-HF). MEASUREMENTS: The appendicular skeletal muscle mass of the arms and the legs combined was assessed by dual energy x-ray absorptiometry (DEXA). Sarcopenia was defined as the appendicular muscle mass two standard deviations below the mean of a healthy reference group of adults aged 18 to 40 years, as suggested for the diagnosis of muscle wasting in healthy aging. All patients underwent a 6-minute walk test and spiroergometry testing. Forearm and leg blood flow were measured by venous occlusion plethysmography. Peak blood flow was assessed after a period of ischemia in the limbs to test endothelial function. RESULTS: Sarcopenia was identified in 37 patients (19.5%). Patients with sarcopenia presented with lower baseline forearm blood flow (2.30 ± 1.21 vs. 3.06 ± 1.49 vs. 4.00 ± 1.66 mL min-1 100 mL-1; P = .02) than those without sarcopenia or controls. The group of patients with sarcopenia showed similar baseline leg blood flow (2.06 ± 1.62 vs. 2.39 ± 1.39 mL min-1 100 mL-1; P = .11) to those without but lower values when compared to controls (2.06 ± 1.62 vs. 2.99 ± 1.28 mL min-1 100 mL-1; P = .03). In addition, patients with and without sarcopenia presented with lower peak flow in the forearm when compared to controls (18.37 ± 7.07 vs. 22.19 ± 8.64 vs. 33.63 ± 8.57 mL min-1 100 mL-1; P < .001). A similar result was observed in the leg (10.89 ± 5.61 vs. 14.66 ± 7.19 vs. 21.37 ± 13.16 mL min-1 100 mL-1; P < .001). Peak flow in the forearm showed a significant correlation with exercise capacity (relative peak VO2: R = 0.47; P < .001; absolute peak VO2: R = 0.35; P < .001; and 6-min walk distance: R = 0.20; P < .01). Similar correlations were observed between peak flow in the leg and exercise capacity (absolute peak VO2: R = 0.42, P < .001; relative peak VO2: R = 0.41, P < .001; and 6-min walk test: R = 0.33; P < .001). Logistic regression showed peak flow in the leg to be independently associated with the 6-min walk distance adjusted for age, hemoglobin level, albumin, creatinine, presence of sarcopenia, and coronary artery disease (hazard ratio, 0.903; 95% confidence interval, 0.835-0.976; P = .01). CONCLUSION: Patients with HF associated with sarcopenia have impaired endothelial function. Lower vasodilatation had a negative impact on exercise capacity, particularly prevalent in patients with sarcopenia.
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Comorbilidad , Insuficiencia Cardíaca , Sarcopenia , Anciano , Berlin , Estudios Transversales , Femenino , Humanos , Masculino , Persona de Mediana Edad , Músculo Esquelético/fisiopatología , Sarcopenia/fisiopatologíaRESUMEN
INTRODUCTION: The aim of this study was to detect the prevalence of the extended-spectrum beta-lactamase (ESBL)-encoding CTX-M gene in Escherichia coliisolates. METHODS: Phenotypic screening of 376 E. coli isolates for ESBL was conducted using disk diffusion. ESBL-producing isolates were tested using PCR and specific primers. The bla(CTX-M) cluster was identified using the RFLP method, and its genotype was sequenced. RESULTS: From 202 ESBL-producing E. coli , 185 (91.5%) possessed CTX-M genes. CTX-M-1 subtypes were found in 98% of the isolates. The bla(CTX-M) gene was identical to CTX-M-15. CONCLUSIONS: A high prevalence of CTX-M-1-producing E. coli apparently exists in Shiraz, Iran.