Long Term Follow-up Study Of Hypertrophic Cardiomyopathy By Echocardiography

Objective : To study the long-term following-up results and the echocardiograpic characteristics of hypertrophic cardiomyopathy (HCM) patients as time pass by, and to explore the relationship between the outcome and echocardiograpic characteristics.Methods : Two hundred and forty five patients with hypertrophic cardiomyopathy at Department of Cardiology, the First Hospital Affiliated to Soochow University from February 1998 to October 2010 were recruited. Among these , 69 patients were followed up at least 5 years (5～12 years) . Finally 48 patients with detailed information were retrospectively analyzed .All the data were analyzed by SPSS software 15.0. Results:1. A total of 55 out of 69 patients (79.71%) were successfully followed up for 88.77±22.41 months, 14 cases (20.29%) lost to follow-up. Among them,7 died during following-up period (12.72%), of which 6 patients, 5 male , 1 female, aged 17～65(40.40±17.52), died of the HCM-related deaths , and as a result, the 5-year-survival rate was 87.27%. Fifteen patients (27.27%) were diagnosed as obstructive hypertrophic cardiomyopathy; Four patients showed left ventricular ejection fraction (LVEF) < 45%; Eighteen patients ( 32.73%) had a family history of HCM; Thirty five patients(63.64%) were diagnosed as the type of MaronⅢ, 7 were the type of apical myocardial hypertrophy. According to the analysis of echocardiography parameters, we observed myocardial thickness increased in 48 patients, whose thickness was at the beginning 13～36mm(18.81±5.57mm),while at the end 15～39mm(22.31±5.81mm), the difference was statistically significant(P=0.001);the left atrium diameter was respectively (39.50±6.56mm) VS (42.21±7.77mm) before and after the time of following-up ,the difference was significant (P=0.002); So was the parameter left ventricular diastolic function (0.67±0.11) VS (0.96±0.12), and the difference was statistically significant (p = 0.005) before and after following-up.Conclusions: 1. The prognosis of patients with HCM is relatively good, particularly the ones only with apical myocardial hypertrophy. 2. Myocardial thickness and left atrium diameter gradually increased. The diastolic function was also impaired during the long period at the same time. 3. The facts correlated with poor prognosis were family myocardial hypertrophy, family history of sudden cardiac death with myocardial hypertrophy,left ventricular outflow tract obstruction,myocardial thickness≥30mm, New York Heart Association(NYHA) classⅢ～Ⅳ,left atrial increases and atrial fibrillation. We also found that obvious diastolic dysfunction and pulmonary arterial hypertension are the high risk of sudden death in patients with HCM.