微血管密度在肥厚性心肌病合并房颤患者中的变化特点及其影响

Characteristics and significance of changes in microvessel density in patients with hypertrophic cardiomyopathy and atrial fibrillation

目的探讨微血管密度在肥厚性心肌病患者中的变化特点及意义。方法选取2016年3月至2019年10月间在新乡医学院附属南阳市第二人民医院就诊的肥厚性心肌病患者46例, 分为合并房颤组11例, 未合并房颤组35例。心脏核磁共振成像测量左室舒张末期内径、质量指数、容量指数, 以及左心房内径、左室射血分数、室间隔厚度。取患者外科手术切除的室间隔基底部组织标本, 免疫组化检测微血管密度和心肌纤维化百分比。结果合并房颤组左心房内径明显高于未合并房颤组(P<0.05);左室舒张末期内径、质量指数、容积指数以及左室射血分数、室间隔厚度在两组差异无统计学意义(P>0.05)。合并房颤组患者的心肌纤维化水平(18.94±7.60)%, 明显高于未合并房颤组患者的心肌纤维化水平(11.07±6.13)%(P<0.01);合并房颤组患者的微血管密度(348±54)个/mm^(2), 明显低于未合并房颤组患者的微血管密度(519±185)个/mm2(P<0.01)。Pearson相关性分析显示, 全部肥厚性心肌病患者以及合并房颤组、未合并房颤组患者的心肌纤维化水平均与微血管密度呈负相关(均P<0.05)。多元线性回归显示, 微血管密度下降是肥厚性心肌病合并房颤患者心肌纤维化水平升高的独立影响因素(P<0.05)。结论肥厚性心肌病患者中合并房颤者的微血管密度较未合并房颤者明显下降, 微血管密下降是肥厚性心肌病合并房颤患者心肌纤维化水平升高的独立危险因素。

Objective To investigate the characteristics and significance of changes in microvessel density in the patients with hypertrophic cardiomyopathy.Methods Forty-six patients with hypertrophic cardiomyopathy admitted to Nanyang Second Municipal People’s Hospital Affiliated to Xinxiang Medical College between March 2016 and October 2019 were included in the study.There were 11 patients with concomitant atrial fibrillation(AF)and 35 patients without.Left ventricular end diastolic diameter,mass index,volume index,left atrial diameter,left ventricular ejection fraction and interventricular septal thickness were measured by cardiac MRI.The tissue specimen from basal part of interventricular septum was obtained by surgical resection and then subjected to measurement of microvessel density and the percentage of myocardial fibrosis using immunohistochemistry.Results The left atrial diameter in the patients with AF was significantly greater than that in the patients without AF(P<0.05),and there were no statistically significant differences in the end diastolic diameter,mass index,volume index,left ventricular ejection fraction and interventricular septal thickness between the two groups(all P>0.05).The level of myocardial fibrosis in patients with AF was significantly higher than that in patients without AF[(18.94±7.60)%vs(11.07±6.13)%,P<0.01].The microvascular density in patients with AF was significantly lower than that in patients without AF[(348±54)/mm2 vs(519±185)/mm2,(P<0.01)].Pearson correlation analysis showed that there was a negative correlation between the level of myocardial fibrosis and microvessel density among patients with hypertrophic cardiomyopathy and those with and without AF(all P<0.05).Multiple linear regression analysis showed that lowered microvessel density was an independent factor for the increased myocardial fibrosis in patients with hypertrophic cardiomyopathy and AF(P<0.05).Conclusion The microvessel density in the patients with hypertrophic cardiomyopathy and AF is significantly lower than that in the patients without AF.Lowered microvascular density is an independent risk factor for increased myocardial fibrosis in patients with hypertrophic cardiomyopathy and AF.