A case report of a secondary Takotsubo syndrome after sudden cardiac arrest in a teenager with LQTS2

Takotsubo syndrome (TTS) is a condition first identified in the 1990s in the Japanese population. It is believed that 1%–2% of acute coronary syndromes are due to TTS. The pathophysiological mechanism involves acute activation of the sympathetic nervous system with a cataclysmic release of catecholamines, causing acute myocardial dysfunction.

We report a case of an 18-year-old female patient who suffered an out-of-hospital cardiac arrest due to ventricular fibrillation of unknown etiology. Emergency cardiac catheterization revealed normal coronaries and hypokinesia of the apical segments. The patient was admitted to the ICU with refractory cardiogenic shock, necessitating extracorporeal life support measures. Serial echocardiograms showed rapid deterioration of left ventricular function. The diagnosis of TTS was confirmed with an early cardiovascular magnetic resonance study. A corrected QT interval (QTc) prolongation was observed intermittently. The patient showed an excellent neurological outcome and was discharged after implantable cardioverter defibrillator implantation for ambulatory care. Genetic testing revealed a previously unpublished KCNH2 gene mutation. Mutations in this gene are known to cause long QT syndrome (LQTS).

Our case presents a secondary TTS after surviving a sudden cardiac arrest in a teenager with so far unknown LQTS2-associated ventricular fibrillation. We emphasize the importance of repeated electrocardiogram recordings and serial echocardiography in unexplained cardiogenic shock. Our case highlights the importance of an early multimodal therapeutic approach in the management of TTS to improve patient outcomes in this complex clinical entity.