Hypertrophic cardiomyopathy: from diagnosis to prevention

In a 55-year-old man, his two sons aged 32 and 30 years and a 3-year-old grandchild, a gene mutation related to an increased chance of hypertrophic cardiomyopathy was found. The adults had complaints of cardiac arrhythmias varying from dizziness to cardiac arrest and received medication; a defibrillator was also implanted in the case of the sons. Familial hypertrophic cardiomyopathy can be diagnosed in an early stage with DNA screening methods. At that time 'patients' (carriers) often do not exhibit symptoms. This offers the possibility of taking therapeutic measures to prevent or slow down the disease process. However, the scientific basis for preventive therapy is inadequate, so that medical-ethical dilemmas arise which can affect the decision-making process with respect to genetic testing. Additional research must lead to satisfactory preventive therapies, so that in the future the genetic diagnosis 'hypertrophic cardiomyopathy' can be effectively translated into disease prevention.     

Three-Wall Segment (TriSeg) Model Describing Mechanics and Hemodynamics of Ventricular Interaction

A mathematical model (TriSeg model) of ventricular mechanics incorporating mechanical interaction of the left and right ventricular free walls and the interventricular septum is presented. Global left and right ventricular pump mechanics were related to representative myofiber mechanics in the three ventricular walls, satisfying the principle of conservation of energy. The walls were mechanically coupled satisfying tensile force equilibrium in the junction. Wall sizes and masses were rendered by adaptation to normalize mechanical myofiber load to physiological standard levels. The TriSeg model was implemented in the previously published lumped closed-loop CircAdapt model of heart and circulation. Simulation results of cardiac mechanics and hemodynamics during normal ventricular loading, acute pulmonary hypertension, and chronic pulmonary hypertension (including load adaptation) agreed with clinical data as obtained in healthy volunteers and pulmonary hypertension patients. In chronic pulmonary hypertension, the model predicted right ventricular free wall hypertrophy, increased systolic pulmonary flow acceleration, and increased right ventricular isovolumic contraction and relaxation times. Furthermore, septal curvature decreased linearly with its transmural pressure difference. In conclusion, the TriSeg model enables realistic simulation of ventricular mechanics including interaction between left and right ventricular pump mechanics, dynamics of septal geometry, and myofiber mechanics in the three ventricular walls.     

Sudden unexpected death in children with a previously diagnosed cardiovascular disorder

BACKGROUND: It is known that children with previously diagnosed heart defects die suddenly. The causes of death are often unknown. OBJECTIVE: The aim of the study was to identify all infants and children within the Netherlands with previously diagnosed heart disease who had a sudden unexpected death (SUD), and to identify the possible cause of death. DESIGN: Retrospective, cross-sectional study. PATIENTS AND SETTING: All children (<19 years) with a previously diagnosed heart defect and SUD between January 1990 and June 2001 in seven out of eight tertiary centres in the Netherlands were identified using the hospital databases. We excluded patients receiving compassionate care. Diagnoses, clinical status and circumstances of death were sought from case notes and post mortem reports. Deaths were classified as of cardiac or non-cardiac origin. RESULTS: We identified 150 cases of SUD (89 male) at a median age of 2.3 years (range 18 days-18.9 years); 49/150 patients (33%) were 相似文献   

Coil reduction of the right ventricular cavity in a boy with pulmonary atresia, intact ventricular septum, and an aneurysmal coronary sinusoid.

Coronary sinusoids are often found in patients with pulmonary atresia and intact ventricular septum. We report on a 4-year-old boy with such pathology in whom, after completion of the Fontan-circulation, the pulsatile flow through a major sinusoid significantly increased the size of a coronary artery up to aneurysmal dimensions. Because percutaneous closure of the sinusoid was unsuccessful, the right ventricular cavity was partially obliterated with coils. This resulted in a significant decrease of right ventricular stroke volume, regression of the pulsatility and of the coronary size, with good clinical result at 1.5 years of follow-up.     

Neonatal Marfan syndrome: clinical report and review of the literature

The neonatal Marfan syndrome (nMFS) is a rare condition with a poor prognosis. The relative infrequency of this syndrome hampers the clinical diagnosis at an early age. This report describes the progress of a 4-year-old boy with neonatal Marfan syndrome and severe cardiac involvement. Molecular genetic studies showed a de novo point mutation in exon 29 of the FBN1 gene located on chromosome 15q21.1. This mutation is in the classic region for nMFS and has not been reported before. The literature is reviewed. We stress the importance of early recognition of the phenotype in order to anticipate the development of cardiac abnormalities.