New paradigm of familial non compaction associated with hypertrophic cardiomyopathy-an Echocardiogra

• 作 者: 代薇娜
• 机 构: 华中科技大学
• 出 处: 华中科技大学
• 发表日期: 2012年12期
• 关键词: Non Compa

Hypertrophic cardiomyopathy (HCM) is a complex genetically determined myocardial disease with a heterogeneous spectrum.It is the most commonly inherited cardiac disease in the population,occurring in 1:500.There have been studies reporting HCM as the most common cause of sudden cardiac death in those aged less than 30 years and an important predisposition for heart failure,arrhythmias irrespective of age.HCM is characterized by a hypertrophic left ventricle,without ventricular dilation and in the absence of any other cardiac or systemic disease which may have been the cause for the wall thickening.Hypertrophic cardiomyopathy is inherited as a mendelian autosomal dominant trait and caused by mutations in any 1 of 10 genes,each encoding proteins of the cardiac sarcomere.Clinical diagnosis is by 2-dimensional echocardiographic identification of otherwise unexplained left ventricular wall thickening in thepresence of a non dilated cavity in the absence of another cardiac or systemic disease (eg,hypertension or aortic stenosis) capable of producing the magnitude of hypertrophy evident.
　　Recently,NCC and HCM have been linked together by the same disease causing genes.The genetic studies about alpha-cardiac actin gene (ACTC),beta myosin heavy chain gene (MYH7),cardiac troponin T and other sarcomeric gene mutations provide the link between these cardiomyopathies,revealing them as overlapping entities.Previous reports about patients sharing both NCC and HCM phenotypes suggest a strong genetic association.This study involved a four generation Chinese family demonstrating the coexistence of NCC and HCM in the kindreds.An echocardiographic exploration was performed to evaluate its utility as the first diagnostic modality of choice in NCC and HCM.
　　Method:A four generation chinese family,comprising of 30 members was selected (21 male,9 female) amongst which 27 underwent familial screening.7 kindred were recruited in our hospital who were all examined by echocardiography,while some also performed ECG,MRI,left ventricular and coronary artery angiography.Echocardiographic and MRI findings were further compared.
　　Results:Features of LVNC associated with HCM were identified in the proband,aged 48 years,who presented with congestive heart failure.Familial screening by means of UCG/MRI revealed that 11 out of the 27 members suffered from LVNC, HCM or both.The distribution was as follows: 6 HCM & LVNC, 4 HCM and 1 LVNC.Kindred with cardiomyopathies, examined in our hospital numbered to 7 (3 adult males, 2 adult females and 2 children).Amongst them,5 were symptomatic and rest asymptomatic.The diagnoses were as follows: 2 HOCM & LVNC,4 HCM & LVNC,and 1 isolated LVNC.The locations of hypertrophic lesions included IVS,anterior and LV inferior wall,with thickness of 1.6-2.0cm in adult.In addition,the locations of LVNC lesions included anterior,lateral wall, anteroseptum and apex,with the ratio of N/C 2.5-4.4.Echocardiography also demonstrated LA dilatation and a decrease in diastolic function in most of the subjects.As UCG and MRI findings showed similar results,a good correlation in location and quantification of the lesion between these two imaging modalities was established.ECG abnormalities were detected in most of the recruits.
　　Conclusion:LVNC and HCM coexists in this family,thereby supporting the basis of hereditary diseases with shared genetic defects.Phenotypes in this family show similarity but vary in terms of age,clinical manifestations and imaging findings.UCG and MRI findings concerning these diseases were in agreement.Echocardiography is a sensitive and useful as the initial diagnostic tool for these two diseases.Myocardial contrast echocardiography remains a beneficial modality in order to improve echocardiographic imaging in diagnosis of cardiomyopathies.