Tsugawa Jun, Tsuboi Yoshio, Inoue Hirosato, Suzuki Shigeaki, Yamada Tatsuo
Department of Neurology, Fukuoka University School of Medicine.
Rinsho Shinkeigaku. 2011 Jan;51(1):32-4. doi: 10.5692/clinicalneurol.51.32.
We report a 51-year-old man who was admitted to our hospital due to repeated episodes of syncope associated with generalized myasthenic symptoms. Due to myasthenic symptoms with the presence of anti-AchR antoantibody, he was diagnosed as myasthenia gravis (MG) associated with thymoma. However, Holter ECG showed long pause with maximum R-R interval of 3.8 seconds and paroxysmal atrial fibrillation, indicating the diagnosis of sick sinus syndrome. After pace maker implantation and combination therapy with thymomectomy and steroid administration, no arrhythmia in repeated Holter ECG was found. In addition, an anti-kv1.4 antibody was positive in our case. The involvement of cardiomyopathy in patients with MG has been reported, including the association with sudden death. The anti-kv1.4 antibody was recently identified in cases of myasthenia gravis associated with cardiomyositis. After treatments, no arrhythmia was found in our case. Although the cardiomyopathy was not diagnosed in our case because of lacking of histological confirmation, clinical course associated with positive anti-kv1.4 antibody suggested that the cause of syncope might be immune-related cardiomyopathy. To prevent fatal complication of arrhythmia, appropriate examination and therapy against cardiomyopathy associated with myasthenia gravis should be considered.
我们报告一名51岁男性，因反复出现与全身性肌无力症状相关的晕厥发作而入住我院。由于存在抗乙酰胆碱受体自身抗体且伴有肌无力症状，他被诊断为重症肌无力（MG）合并胸腺瘤。然而，动态心电图显示最长R-R间期为3.8秒的长间歇及阵发性心房颤动，提示病态窦房结综合征的诊断。在植入起搏器并联合胸腺切除术及类固醇治疗后，动态心电图复查未发现心律失常。此外，我们的病例中抗kv1.4抗体呈阳性。已有报道MG患者存在心肌病，包括与猝死的关联。抗kv1.4抗体最近在合并心肌炎的重症肌无力病例中被发现。经过治疗，我们的病例未发现心律失常。尽管由于缺乏组织学证实我们的病例未诊断出心肌病，但抗kv1.4抗体阳性相关的临床病程提示晕厥原因可能是免疫相关性心肌病。为预防心律失常的致命并发症，应考虑对重症肌无力相关心肌病进行适当检查和治疗。
