Diagnostic Research In Patients With Concentric Myocardial Hypertrophic Disease

Background:Myocardial hypertrophic disease is a genetically determined or sometimes acquired disorder of heart muscle, which can be divided into non-concentric hypertrophy and concentric hypertrophy. Non-concentric hypertrophy usually refers to hypertrophic cardiomyopathy, while the majority of concentric of hypertrophy is due to hypertension, aortic valve stenosis. However, there are still many cases of concentric hypertrophy we couldn’t make the diagnosis. As new diagnostic technology develops, some of cases are well diagnosed.Methods:Retrospective and prospective research methods are used in the present study. The first two parts are retrospective studies. The electrocardiographic and echocardiographic characteristics were analyzed in patients with clinically diagnosed cardiac amyloidosis, classical electrocardiographic features were summarized and the combined indexes of electrocardiography and echocardiography were put forward as the noninvasive diagnositics for cardiac amyloidosis. The last two parts were prospective studies. Electron microscopy and genetics analysis were used for other types of unknown concentric myocardial hypertrophic diseases.Results:(1) Low voltage and pseudo-infarction morphology are the most common electrocardiographic characteristics of the cardiac amyloidosis patients. The sensitivity, specificity, positive predictive value and negative predictive value for making the diagnosis is 28%,98%,96% and 39%, respectively. (2) Electrocardiography, combined with echocardiography, can be the noninvasive test. The ratio of R1/LVPW< 0.4 for the diagnosis of cardiac amyloidosis, the sensitivity and specificity is 91% and 100%, respectively. And the positive and negative predictive value is 100% and 91%. As well, the ratio of RV5(6)/LVPW< 0.7 for the diagnosis of cardiac amyloidosis, the sensitivity and specificity is 91% and 89%, respectively. And the positive and negative predictive value is 91% and 89%. (3) It is helpful to take electron microscopy examinations in suspected patients with negative Congo red staining for making the final diagnosis. (4)Danon disease is a rare disorder, which may account for a number of patients with concentric LVH. Genetic analysis of LAMP2, endomyocardial biopsy and electron microscopic examinations may help to make a diagnosis. And we find three new novel mutations of the LAMP2 gene.Conclusions:Low voltage and pseudo-infarction morphology are the classical features of patients with cardiac amyloidosis. The combined indexes of electrocardiography and echocardiography could be as the novel noninvasive diagnositics for the diagnosis of cardiac amyloidosis. Electro microscopy is a helpful tool for patients with suspected cardiac amyloidosis but negative Congro red staining. Danon disease is one of the cause in patients with concentric myocardial hypertrophic disease.