We describe three children with Noonan syndrome with cardiopathy. One female child had cardiopathy and ocular abnormalities. The other two male children had congenital heart disease of which one had uncommon association of tricuspid valve dysplasia with regurgitation associated with endocardial cushion defect. Karyotypes of the female and one of the male children were normal. The growth hormone and thyroid hormone studies in the first and second male children were normal. All the three children were managed conservatively and followed-up.
Cardiac sarcoidosis is a disease of young adults. In most cases it presents with sudden death, arrhythmias, conduction disorders, heart failure or cardiomyopathy. The authors describe two cases of myocardial involvement by sarcoidosis that lead to death of the patients. Case one was a 26-year-old Indian man who was previously well and presented with sudden death. Autopsy showed nodules of sarcoid granuloma involving the heart, lungs and lymph nodes. Case two was a 47-year-old Indian lady who complained of reduced effort tolerance. Echocardiography showed that she had restrictive hypertrophic cardiomyopathy with heart failure. Seven months after initial presentation, she developed worsening of heart failure and died. Autopsy revealed involvement of the heart, lungs and liver by sarcoidosis.
Heart failure is a major killer worldwide. Atrioventricular conduction block is common in heart failure; it is associated with worse outcomes and can lead to syncope and bradycardic death. We examine the effect of heart failure on anatomical and ion channel remodelling in the rabbit atrioventricular junction (AVJ). Heart failure was induced in New Zealand rabbits by disruption of the aortic valve and banding of the abdominal aorta resulting in volume and pressure overload. Laser micro-dissection and real-time polymerase chain reaction (RT-PCR) were employed to investigate the effects of heart failure on ion channel remodelling in four regions of the rabbit AVJ and in septal tissues. Investigation of the AVJ anatomy was performed using micro-computed tomography (micro-CT). Heart failure animals developed first degree heart block. Heart failure caused ventricular myocardial volume increase with a 35% elongation of the AVJ. There was downregulation of HCN1 and Cx43 mRNA transcripts across all regions and downregulation of Cav1.3 in the transitional tissue. Cx40 mRNA was significantly downregulated in the atrial septum and AVJ tissues but not in the ventricular septum. mRNA abundance for ANP, CLCN2 and Navβ1 was increased with heart failure; Nav1.1 was increased in the inferior nodal extension/compact node area. Heart failure in the rabbit leads to prolongation of the PR interval and this is accompanied by downregulation of HCN1, Cav1.3, Cx40 and Cx43 mRNAs and anatomical enlargement of the entire heart and AVJ.