Fredlund B O, Olsson S B
Acta Med Scand. 1983;213(3):231-5. doi: 10.1111/j.0954-6820.1983.tb03724.x.
We have observed two patients with long QT interval, ventricular tachycardias of "torsade de pointe" type and repeated ventricular fibrillation episodes, who also turned out to have significant hypothyroidism. This was suspected from the clinical picture in one patient and after haematological test in the other. In addition to hypothyroidism, both patients had associated factors which may have contributed to the development of the arrhythmia. After having reached an euthyroid state, both patients normalized their QT intervals, were relieved from earlier symptoms of cardiac arrhythmias and exhibited no longer any documented arrhythmia. Before thyroid substitution, both patients had marked signs of delayed ventricular repolarization even by invasive electrophysiological methods. Our observations indicate that hypothyroidism should be considered a possible primary cause in cases with long QT syndrome (LQTS). Furthermore, the possibility of LQTS in patients with hypothyroidism should be considered.
我们观察了两名长QT间期、伴有尖端扭转型室性心动过速及反复室颤发作的患者，结果发现他们均患有严重甲状腺功能减退症。其中一名患者从临床表现怀疑该病，另一名则是在血液学检查后确诊。除甲状腺功能减退外，两名患者均有相关因素，可能促使心律失常的发生。甲状腺功能恢复正常后，两名患者的QT间期均恢复正常，早期心律失常症状缓解，且未再有记录到的心律失常。在进行甲状腺替代治疗前，即使通过有创电生理检查方法，两名患者也有明显的心室复极延迟迹象。我们的观察表明，甲状腺功能减退症应被视为长QT综合征（LQTS）病例可能的主要病因。此外，也应考虑甲状腺功能减退症患者发生LQTS的可能性。
