Renal Denervation Reduced Ventricular Arrhythmia After Myocardial Infarction by Inhibiting Sympathetic Activity and Remodeling.

Background Ventricular arrhythmia after myocardial infarction is the most important risk factor for sudden cardiac death, which poses a serious threat to human health. As the correlation between autonomic nervous systemic dysfunction and heart rhythm abnormality has been gradually revealed, remedies targeting autonomic nervous system dysfunction, especially the sympathetic nerve, have emerged. Among them, renal denervation is noted for its powerful effect on the inhibition of sympathetic nerve activity. We aim to investigate whether renal denervation can reduce ventricular arrhythmia after myocardial infarction and thus decrease the risk of sudden cardiac death. In addition, we explore the potential mechanism with respect to nerve activity and remodeling. Methods and Results Twenty-four beagles were randomized into the control (n=4), renal denervation (n=10), and sham (n=10) groups. Permanent left anterior descending artery ligation was performed to establish myocardial infarction in the latter 2 groups. Animals in the renal denervation group underwent both surgical and chemical renal denervation. Compared with dogs in the sham group, dogs in the renal denervation group demonstrated attenuated effective refractory period shortening and inhomogeneity, flattened restitution curve, increased ventricular threshold, and decreased ventricular arrhythmia. Heart rate variability assessment, catecholamine measurement, and nerve discharge recordings all indicated that renal denervation could reduce whole-body and local tissue sympathetic tone. Tissue analysis revealed a significant decrease in neural remodeling in both the heart and stellate ganglion. Conclusions Surgical and chemical renal denervation decreased whole-body and local tissue sympathetic activity and reversed neural remodeling in the heart and stellate ganglion. Consequently, renal denervation led to beneficial remodeling of the electrophysiological characteristics in the infarction border zone, translating to a decrease in ventricular arrhythmia after myocardial infarction.

Association of Severity of Coronary Lesions with Bone Mineral Density in Postmenopausal Women.

BACKGROUND: Coronary artery disease (CAD) and osteoporosis (OP) are common diseases in postmenopausal women. In both cross-sectional and longitudinal epidemiologic studies, low bone mass has been related to increased frequency of CAD. However, available data on the relationship between bone mineral density (BMD) and severity of coronary lesions is limited. OBJECTIVE: To investigate association between the BMD and severity of coronary lesions assessed by Gensini score in postmenopausal women. METHODS: This study included 122 postmenopausal women who were diagnosed with CAD. These patients were divided into two groups according to the severity of coronary lesions assessed by the Gensini score - patients with mild coronary lesions (Gensini score < 25) and patients with severe coronary lesions (Gensini score ≥ 25). Femoral neck mineral density was measured with dual energy X-ray absorptiometry (DXA). RESULTS: The study included postmenopausal women aged 64.31 ± 4.71 years, 85 of whom (69.7%) exhibited severe coronary lesions. Participants with severe coronary lesions had a significantly higher T score than did those with mild coronary lesions at the femoral neck (p < 0.05). The mean T-score was -0.84 ± 1.01 in mild coronary lesions group, -1.42 ± 1.39 in severe coronary lesions group (p < 0.05). Multivariable logistic regression analysis showed that osteopenia-osteoporosis at the Femoral neck (odds ratio 2.73; 95% confidence interval 1.06 to 6.13) was associated with an increased risk of developing severe coronary lesions. The multiple regression model showed that T-scores (b = -0.407, SE = 0.151, p=0.007) were the independent predictors of Gensini score. CONCLUSION: The relationship between severity of coronary lesions and BMD was significant in postmenopausal women. BMD, a low-cost technique involving minimal radiation exposure, widely used for osteoporosis screening, is a promising marker of severity of coronary lesions.

Association of Severity of Coronary Lesions with Bone Mineral Density in Postmenopausal Women / Associação entre Gravidade das Lesões Coronarianas e Densidade Mineral Óssea em Mulheres Pós-Menopausa

Abstract Background: Coronary artery disease (CAD) and osteoporosis (OP) are common diseases in postmenopausal women. In both cross-sectional and longitudinal epidemiologic studies, low bone mass has been related to increased frequency of CAD. However, available data on the relationship between bone mineral density (BMD) and severity of coronary lesions is limited. Objective: To investigate association between the BMD and severity of coronary lesions assessed by Gensini score in postmenopausal women. Methods: This study included 122 postmenopausal women who were diagnosed with CAD. These patients were divided into two groups according to the severity of coronary lesions assessed by the Gensini score - patients with mild coronary lesions (Gensini score < 25) and patients with severe coronary lesions (Gensini score ≥ 25). Femoral neck mineral density was measured with dual energy X-ray absorptiometry (DXA). Results: The study included postmenopausal women aged 64.31 ± 4.71 years, 85 of whom (69.7%) exhibited severe coronary lesions. Participants with severe coronary lesions had a significantly higher T score than did those with mild coronary lesions at the femoral neck (p < 0.05). The mean T-score was −0.84 ± 1.01 in mild coronary lesions group, −1.42 ± 1.39 in severe coronary lesions group (p < 0.05). Multivariable logistic regression analysis showed that osteopenia-osteoporosis at the Femoral neck (odds ratio 2.73; 95% confidence interval 1.06 to 6.13) was associated with an increased risk of developing severe coronary lesions. The multiple regression model showed that T-scores (b = −0.407, SE = 0.151, p=0.007) were the independent predictors of Gensini score. Conclusion: The relationship between severity of coronary lesions and BMD was significant in postmenopausal women. BMD, a low-cost technique involving minimal radiation exposure, widely used for osteoporosis screening, is a promising marker of severity of coronary lesions.

Resumo Fundamento: A doença arterial coronariana (DAC) e a osteoporose são doenças comuns em mulheres pós-menopausa. Tanto em estudos transversais como em estudos epidemiológicos longitudinais, a massa óssea diminuída foi relacionada à frequência aumentada de DAC. No entanto, dados disponíveis sobre a relação entre densidade mineral óssea (DMO) e gravidade das lesões coronarianas são limitados. Objetivo: Investigar a associação entre DMO e gravidade das lesões coronarianas avaliadas pelo escore de Gensini em mulheres pós-menopausa. Métodos: Este estudo incluiu 122 mulheres pós-menopausa diagnosticadas com DAC. As pacientes foram divididas em dois grupos de acordo com a gravidade das lesões coronarianas avaliada pelo escore de Gensini - pacientes com lesões coronarianas leves (escore de Gensini < 25) e pacientes com lesões coronarianas graves (escore de Gensini ≥ 25). A densidade mineral do colo femoral foi medida por absorção de raios-X de dupla energia (DXA). Resultados: O estudo incluiu mulheres pós-menopausa com idade de 64,31 ± 4,71 anos, 85 delas (69,7%) com lesões coronarianas graves. Pacientes com lesões coronarianas graves apresentaram um escore T mais elevado que aquelas com lesões coronarianas leves no colo femoral (p < 0,05). O escore T médio foi -0,84 ± 1,01 no grupo com lesões leves, e -1,42 ± 1,39 no grupo com lesões graves (p < 0,05). A análise de regressão logística multivariada mostrou que a osteopenia-osteoporose no colo femoral (odds ratio 2,73; intervalo de confiança de 95% 1,06 - 6,13) esteve associada com um risco aumentado de se desenvolver lesões coronarianas graves. O modelo de regressão múltipla mostrou que os escores T (b = -0,407; EP= 0,151; p = 0,007) foram preditores independentes do escore de Gensini. Conclusão: Encontrou-se uma relação significativa entre a gravidade das lesões coronarianas e a DMO em mulheres pós-menopausa. DMO, uma técnica de baixo custo que envolve mínima exposição à radiação, e amplamente utilizada no rastreamento de osteoporose, é um marcador promissor da gravidade de lesões coronarianas graves.