Background-The role of structural heart disease and sodium channel dysfunction in the induction of electrical instability in Brugada syndrome is still debated. Methods and Results-We studied 18 consecutive patients (15 males, 3 females; mean age 42.0Ϯ12.4 years) with clinical phenotype of Brugada syndrome and normal cardiac structure and function on noninvasive examinations. Clinical presentation was ventricular fibrillation in 7 patients, sustained polymorphic ventricular tachycardia in 7, and syncope in 4. All patients underwent cardiac catheterization, coronary and ventricular angiography, biventricular endomyocardial biopsy, and DNA screening of the SCN5A gene. Biopsy samples were processed for histology, electron microscopy, and molecular screening for viral genomes. Microaneurysms were detected in the right ventricle in 7 patients and also in the left ventricle in 4 of them. Histology showed a prevalent or localized right ventricular myocarditis in 14 patients, with detectable viral genomes in 4; right ventricular cardiomyopathy in 1 patient; and cardiomyopathic changes in 3. Genetic studies identified 4 carriers of SCN5A gene mutations that cause in vitro abnormal function of mutant proteins. In these patients, myocyte cytoplasm degeneration was present at histology, whereas terminal dUTP nick end-labeling assay showed a significant increase of apoptotic myocytes in right and left ventricle versus normal controls (Pϭ0.014 and Pϭ0.013, respectively).
Conclusions-Despite
We demonstrate for the first time that CgA is produced by human myocardium and exerts negative inotropic and lusitropic effects on mammalian heart. CgA may represent a key player in neuroendocrine regulation of cardiac function and a potential therapeutic target in heart failure.
Background-Fabry disease (FD) has been recognized as the cause of left ventricular hypertrophy in 6% of men with late-onset hypertrophic cardiomyopathy (HCM). Although FD is considered a recessive X-linked disorder, affected women are increasingly reported. The aim of our study was to determine the prevalence of FD in female patients with HCM. Methods and Results-Thirty-four consecutive women (mean age, 50Ϯ13.6 years) who received an ECG and echocardiographic diagnosis of HCM were submitted to an invasive cardiac study that included a biventricular endomyocardial biopsy. Tissue samples were analyzed for histology and electron microscopy. Peripheral blood activity of ␣-galactosidase (␣-Gal) A was assessed in all patients. None of them had a family history of FD. Histology and electron microscopy showed in 4 patients (12%; mean age, 51.5Ϯ3.9 years) the presence of cell vacuoles characterized by the accumulation of glycolipid material organized in concentric lamellar structures, diagnostic for FD. In the remaining patients, histology was consistent with HCM. In all the female carriers, the heart was the only organ clinically involved in the disease, showing concentric hypertrophy in 2 patients, asymmetric hypertrophy in 1, and apical hypertrophy in 1. The ␣-Gal A enzymatic activity was 44Ϯ14% of control values. Genetic analysis showed the presence of ␣-Gal A gene mutation in all 4 cases. Conclusions-FD may account for up to 12% of females with late-onset HCM. Those heterozygous for FD with left ventricular hypertrophy are potential candidates for enzyme enhancement/replacement therapy.
Fabry disease (FD) is an X-linked lysosomal storage disorder caused by pathogenic variants in the-galactosidase A (GLA) gene that leads to reduced or undetectable-galactosidase A enzyme activity and progressive accumulation of globotriaosylceramide and its deacylated form globotriaosylsphingosine in cells throughout the body. FD can be multisystemic with neurological, renal, cutaneous and cardiac involvement or be limited to the heart. Cardiac involvement is characterized by progressive cardiac hypertrophy, fibrosis, arrhythmias, heart failure and sudden cardiac death. The cardiac management of FD requires specific measures including enzyme replacement therapy or small pharmacological chaperones in patients carrying amenable pathogenic GLA gene variants and more general management of cardiac symptoms and complications. In this paper, we summarize current knowledge of FD-related heart disease and expert consensus recommendations for its management.
Contrast-enhanced cardiac magnetic resonance identified areas of myocardial inflammation in up to 70% of patients with biopsy-proven CM. We suggest that CE-CMR may be a useful non-invasive diagnostic tool in patients with CM, and it may indicate and even guide the execution of left ventricular EMB with relevant prognostic and therapeutic implications.
High mobility group box 1 protein (HMGB1) is a chromatin component leaked out by necrotic cells and actively secreted by activated myeloid cells. The extracellular protein is a potent mediator of tissue remodeling. We show here that human atherosclerotic plaques, but not normal arteries, produce extracellular HMGB1. Secreted HMGB1 originates from endothelial cells, by neointimal foam cells, and also smooth muscle cells (SMCs). SMCs are an unexpected source for secreted HMGB1, since they normally express much lower amounts of HMGB1 than other cells types, and they do not secrete it. However, cultured SMCs actively secrete HMGB1 after cholesterol loading. In turn, in response to HMGB1, SMCs proliferate, migrate, and secrete more HMGB1. Thus, SMCs are both a source and a target of HMGB1; blocking HMGB1 secretion by SMCs can be an important strategy for treatment of atherosclerotic disease and in particular restenosis.
Background-Both celiac disease (CD) and myocarditis can be associated with systemic autoimmune disorders; however, the coexistence of the 2 entities has never been investigated, although its identification may have a clinical impact. Methods and Results-We screened the serum of 187 consecutive patients with myocarditis (118 males and 69 females, mean age 41.7Ϯ14.3 years) for the presence of cardiac autoantibodies, anti-tissue transglutaminase (IgA-tTG), and anti-endomysial antibodies (AEAs). IgA-tTG-positive and AEA-positive patients underwent duodenal endoscopy and biopsy and HLA analysis. Thirteen of the 187 patients were positive for IgA-tTG, and 9 (4.4%) of them were positive for AEA. These 9 patients had iron-deficient anemia and exhibited duodenal endoscopic and histological evidence of CD. CD was observed in 1 (0.3%) of 306 normal controls (PϽ0.003). In CD patients, myocarditis was associated with heart failure in 5 patients and with ventricular arrhythmias (Lown class III-IVa) in 4 patients. From histological examination, a lymphocytic infiltrate was determined to be present in 8 patients, and giant cell myocarditis was found in 1 patient; circulating cardiac autoantibodies were positive and myocardial viral genomes were negative in all patients. HLA of the patients with CD and myocarditis was DQ2-DR3 in 8 patients and DQ2-DR5(11)/DR7 in 1 patient. The 5 patients with myocarditis and heart failure received immunosuppression and a gluten-free diet, which elicited recovery of cardiac volumes and function. The 4 patients with arrhythmia, after being put on a gluten-free diet alone, showed improvement in the arrhythmia (Lown class I). Conclusions-A common autoimmune process toward antigenic components of the myocardium and small bowel can be found in Ͼ4% of the patients with myocarditis. In these patients, immunosuppression and a gluten-free diet can be effective therapeutic options.
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