Contribution of hypoxia-inducible factor 1alpha to pathogenesis of sarcomeric hypertrophic cardiomyopathy.

Hypertrophic cardiomyopathy (HCM) caused by autosomal-dominant mutations in genes coding for structural sarcomeric proteins, is the most common inherited heart disease. HCM is associated with myocardial hypertrophy, fibrosis and ventricular dysfunction. Hypoxia-inducible transcription factor-1α (Hif-1α) is the central master regulators of cellular hypoxia response and associated with HCM.

Trametinib alters contractility of paediatric Noonan syndrome-associated hypertrophic myocardial tissue slices.

Aims: No curative treatment is available for RASopathy-associated childhood-onset hypertrophic cardiomyopathy (RAS-CM). Preclinical data and individual reports suggest a beneficial effect of small molecules targeting the RAS-mitogen-activated protein (MAP) kinase (MAPK) pathway in severely affected RAS-CM patients. The aim of this study was to evaluate the biophysical effects of trametinib, rapamycin and dasatinib on cultivated myocardial tissue slices of a paediatric RAS-CM patient using biomimetic cultivation chambers (BMCCs) and to correlate the findings with clinical data.

EGFR and MMP-9 are associated with neointimal hyperplasia in systemic-to-pulmonary shunts in children with complex cyanotic heart disease.

Systemic-to-pulmonary shunt malfunction contributes to morbidity in children with complex congenital heart disease after palliative procedure. Neointimal hyperplasia might play a role in the pathogenesis increasing risk for shunt obstruction. The aim was to evaluate the role of epidermal growth factor receptor (EGFR) and matrix-metalloproteinase 9 (MMP-9) in the formation of neointimal within shunts.

Molecular signaling pathways in right ventricular impairment of adult patients after tetralogy of Fallot repair.

Background: Right ventricular impairment (RVI) secondary to altered hemodynamics contributes to morbidity and mortality in adult patients after tetralogy of Fallot (TOF) repair. The goal of this study was to describe signaling pathways contributing to right ventricular (RV) remodeling by analyzing over lifetime alterations of RV gene expression in affected patients.

Methods: RV tissue was collected at the time of cardiac surgery in 13 patients with a diagnosis of TOF.

Cell cycle defects underlie childhood-onset cardiomyopathy associated with Noonan syndrome.

Childhood-onset myocardial hypertrophy and cardiomyopathic changes are associated with significant morbidity and mortality in early life, particularly in patients with Noonan syndrome, a multisystemic genetic disorder caused by autosomal dominant mutations in genes of the Ras-MAPK pathway. Although the cardiomyopathy associated with Noonan syndrome (NS-CM) shares certain cardiac features with the hypertrophic cardiomyopathy caused by mutations in sarcomeric proteins (HCM), such as pathological myocardial remodeling, ventricular dysfunction, and increased risk for malignant arrhythmias, the clinical course of NS-CM significantly differs from HCM. This suggests a distinct pathophysiology that remains to be elucidated.