Why heart contractions are weaker in those with hypertrophic cardiomyopathy

(McGill University) Familial hypertrophic cardiomyopathy (HCM) is the most common genetic heart disease in the US and affects an estimated 1 in 500 people around the world. A protein called myosin acts as the molecular motor which makes the muscles in the heart contract. An international team has discovered that in transgenic rabbits with the R403Q mutation,, individual myosin molecules and myofibrils (the basic rod-like filaments inside muscles) produce less force and a lower maximum velocity of contraction than those isolated from healthy hearts.
Source: EurekAlert! - Medicine and Health - Category: International Medicine & Public Health Source Type: news

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Noonan syndrome (NS), and autosomal dominant disorder, is the second most common genetic syndrome associated with congenital heart disease. Over 80% of patients with NS have cardiac involvement and the most common lesions are pulmonary stenosis, atrial septal defects (ASD), and hypertrophic cardiomyopathy (HCM). There clearly is a dearth of data with respect to outcomes after heart surgery for NS patients. The authors from the Mayo Clinic should be congratulated for putting together this valuable information spanning 16 years and including 29 patients.
Source: Seminars in Thoracic and Cardiovascular Surgery - Category: Cardiovascular & Thoracic Surgery Authors: Tags: CONGENITAL – Editorial Commentary Source Type: research
Discussion Barth syndrome is characterized by a dilated cardiomyopathy, proximal skeletal muscle weakness, neutropenia and short stature that usually presents at birth or soon after. It is a rare X-linked recessive disease process caused by mutations in the TAZ gene. The TAZ gene codes for tafazzin which alters cardiolipin in mitochondria. Characteristic facies can be seen especially in infancy including a tall and broad forehead, prominent chin and full cheeks, larger ears, and deep-set eyes. Most patients present at birth or soon afterwards but some may not until later in life. Life expectancy is reduced with many childr...
Source: PediatricEducation.org - Category: Pediatrics Authors: Tags: Uncategorized Source Type: news
The protein kinase C (PKC) and closely related protein kinase N (PKN) families of serine/threonine protein kinases play crucial cellular roles. Both kinases belong to the AGC subfamily of protein kinases that also include the cAMP dependent protein kinase (PKA), protein kinase B (PKB/AKT), protein kinase G (PKG) and the ribosomal protein S6 kinase (S6K). Involvement of PKC family members in heart disease has been well documented over the years, as their activity and levels are mis-regulated in several pathological heart conditions, such as ischemia, diabetic cardiomyopathy, as well as hypertrophic or dilated cardiomyopathy.
Source: Journal of Molecular and Cellular Cardiology - Category: Cytology Authors: Tags: Review article Source Type: research
Abstract Genetic cardiomyopathies, a group of cardiovascular disorders based on ventricular morphology and function, are among the leading causes of morbidity and mortality worldwide. Such genetically driven forms of hypertrophic (HCM), dilated (DCM), and restrictive (RCM) cardiomyopathies are chronic, debilitating diseases that result from biomechanical defects in cardiac muscle contraction and frequently progress to heart failure (HF). Locus and allelic heterogeneity, as well as clinical variability combined with genetic and phenotypic overlap between different cardiomyopathies, have challenged proper clinical p...
Source: Pflugers Archiv : European Journal of Physiology - Category: Physiology Authors: Tags: Pflugers Arch Source Type: research
Abstract Friedreich's ataxia (FRDA), which occurs in 1/50000 live births, is the most prevalent inherited neuromuscular disorder. Nearly all FRDA patients develop cardiomyopathy at some point in their lives. The clinical manifestations of FRDA include ataxia of the limbs and trunk, dysarthria, diabetes mellitus, and cardiac diseases. However, the broad clinical spectrum makes FRDA difficult to identify. The diagnosis of FRDA is based on the presence of suspicious clinical factors, the use of the Harding criteria and, more recently, the use of genetic testing for identifying the expansion of a triplet nucleotide se...
Source: World Journal of Cardiology - Category: Cardiology Authors: Tags: World J Cardiol Source Type: research
CONCLUSION: After this assessment, five athletes were not allowed to practice sport. This study shows the necessity of a thorough cardiological assessment of athletes with ventricular arrhythmia in order to detect underlying heart disease and prevent sudden death in this young apparently healthy population. PMID: 30683482 [PubMed - as supplied by publisher]
Source: Annales de Cardiologie et d'Angeiologie - Category: Cardiology Authors: Tags: Ann Cardiol Angeiol (Paris) Source Type: research
In conclusion, EIPH was documented in about one-third of HCM patients. EIPH was a significant predictor of HCM-related morbidity in patients with HCM.
Source: The International Journal of Cardiovascular Imaging - Category: Radiology Source Type: research
Publication date: January 2019Source: The Annals of Thoracic Surgery, Volume 107, Issue 1Author(s): Meng Li, Li Zhang, Ziming Zhang, Shuyuan Wang, Nianguo Dong, Guohua Wang, Mingxing XieA 26-year-old woman with a diagnosis of congenital heart disease was admitted to the hospital with exertional dyspnea, cyanotic complexion, and bilateral lower limb edema. All tests revealed isolated severe right ventricular hypertrophy. She was in poor condition, with a diminishing chance for routine surgical treatment, so she was scheduled for orthotopic homologous heart transplantation. After the operation, isolated severe right ventricu...
Source: The Annals of Thoracic Surgery - Category: Cardiovascular & Thoracic Surgery Source Type: research
Hypertrophic cardiomyopathy is a genetic heart disease with heterogeneous clinical features, including progression to advanced heart failure. The development of these symptoms can be related to outflow obstruction but in some patients reflects an underlying process of fibrosis and progressive ventricular dysfunction. For patients with end-stage disease, traditional heart failure therapies have not proved beneficial. As such, more advanced therapies, such as left ventricular assist device or cardiac transplantation, should be considered for these patients. Although left ventricular assist device support is used infrequently...
Source: Cardiology Clinics - Category: Cardiology Authors: Source Type: research
ConclusionsImprovements in technology, implant technique and device programming, along with appropriate patient selection, have led to outstanding acute and long-term results, especially regarding the absence of both IS and complications requiring surgical revision.ResumenIntroducción y objetivosEl desfibrilador subcutáneo (S-ICD) surge como alternativa al transvenoso. La incidencia de complicaciones es similar, y los choques inapropiados (CI) son más frecuentes que lo observado con programaciones contemporáneas en los transvenosos. Tras aprobarse en 2009 en Europa, se han implementado diversas ...
Source: Revista Espanola de Cardiologia - Category: Cardiology Source Type: research
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