心脏M2乙酰胆碱能受体自身抗体与肥厚型心肌病的相关性研究

摘要

Objectives: To study serum level of M2-muscarinic receptor autoantibody (M2-AAb) in hypertrophic cardiomyopathy (HCM) patients with its relationship to relevant clinical parameters. Methods: Our research included in 2 groups: HCM group, 133 patients and they were divided into 3 subgroups:Obstructive hypertrophic cardiomyopathy (HOCM) subgroup, 72, Latent obstructive hypertrophic cardiomyopathy (LHOCM) subgroup, 22 and Non-obstructive hypertrophic cardiomyopathy (NOCM) subgroup, 39; since there was no obstruction of left ventricular outflow tract (LVOT) in LHOCM and NOCM patients at resting, LHOCM and NOCM patients were combined as LHOCM+NOCM subgroup, 61 in comparison with HOCM subgroup. And Control group, 40 subjects had no organic heart disease and autoimmune diseases which were confirmed by 12 lead ECG, transthoracic echocardiography and routine hematological tests, they were not using β-blockers, glucocorticoids and immune-suppressants. Serum levels of M2-AAb were examined by ELISA, the relationship between M2-AAb and relevant clinical parameters were studied. Results: Compared with Control group, HCM group had increased serum level of M2-AAb [22.91 (17.21, 29.64) ng/ml] vs (17.14±5.66) ng/ml, P<0.01; M2-AAb was similar among HOCM, LHOCM and NOCM subgroups; M2-AAb in female patients were higher than male, P=0.001. Further investigation presented that the patients with family history of sudden death had the higher M2-AAb, P<0.05; patients with atrial fibrillation (AF) or left atrial diameter (LAD)≥50 mm or moderate to severe mitral regurgitation (MR) had the higher M2-AAb than those without such problems, all P<0.05. In HCM group, log M2-AAb was positively related to resting LVOT gradient (r=0.178, P=0.040); in HOCM subgroup, log M2-AAb was marginal positively related to resting LVOT gradient (r=0.224, P=0.058). Conclusions: Serum M2-AAb was elevated in HCM patients; gender, family history of sudden death may affect M2-AAb level; patients combining AF or LAD≥50 mm or moderate-severe MR had the higher M2-AAb and it was related to resting LVOT gradient.%目的:研究肥厚型心肌病(HCM)患者血清M2乙酰胆碱能受体自身抗体(M2-AAb)的浓度及其与临床指标的关系.方法:连续入选133例HCM患者为HCM组.HCM组进一步分为梗阻性肥厚型心肌病(HOCM)亚组(72)、隐匿梗阻性肥厚型心肌病(LHOCM)亚组(22)、非梗阻性肥厚型心肌病(NOCM)亚组(39),由于静息状态采血时LHOCM和NOCM患者均无左心室流出道(LVOT)梗阻,又将LHOCM、NOCM患者归为LHOCM+NOCM亚组(61),并与HOCM亚组作比较.另选择经12导联心电图、经胸超声心动图及血液学常规检验结果证实无器质性心脏病及自身免疫性疾病,且未服用β受体阻滞剂、糖皮质激素及免疫抑制剂的40例受试者为正常对照组.所有入选者取外周静脉血血清通过酶联免疫吸附法(ELISA)测定M2-AAb浓度.收集患者的临床资料,研究血清M2-AAb浓度与临床指标的关系.结果:HCM组患者血清M2-AAb浓度[22.91(17.21, 29.64)ng/ml]显著高于正常对照组[(17.14±5.66) ng/ml, P<0.01],且HOCM亚组、LHOCM亚组和NOCM亚组患者两两比较血清M2-AAb浓度差异均无统计学意义.女性HCM患者M2-AAb浓度显著高于男性(P=0.001).进一步分析显示,有猝死家族史者M2-AAb浓度显著高于无猝死家族史者(P<0.05).合并心房颤动、左心房内径≥50 mm或合并中-重度二尖瓣反流的患者的血清M2-AAb浓度显著高于不合并这些特征者(P均<0.05).HCM患者logM2-AAb与静息状态LVOT压力阶差呈显著正相关(r=0.178, P=0.040),与HOCM组静息LVOT压力阶差呈临界性正相关(r=0.224,P=0.058).结论:HCM患者血清M2-AAb浓度显著高于正常人群,性别、是否有猝死家族史可能影响其浓度.合并心房颤动、或左心房内径≥50 mm或合并中-重度二尖瓣反流的HCM患者血清M2-AAb水平显著升高.HCM患者血清M2-AAb浓度与静息状态LVOT压力阶差相关.