Syncope in a new mother: a case of long-QT syndrome presenting after childbirth

Diagnosis of inherited arrhythmia syndromes, including long-QT syndrome (LQTS), is challenging; however, early detection and initiation of therapies can reduce otherwise high rates of mortality.

Two months following the birth of her first child a previously well 21-year-old female experienced four episodes of transient loss of consciousness (TLOC). 

The history was atypical for seizures but a video electroencephalogram (EEG) captured an episode with abnormal bifrontal epileptic discharge. She was commenced on levetiracetam. 

Within weeks of the birth of her second child she experienced five further episodes. During the subsequent hospital admission an electrocardiogram (ECG) recorded polymorphic ventricular tachycardia (VT) during a typical TLOC event. Other ECGs recorded a prolonged QT interval. A diagnosis of LQTS was made and TLOC episodes ceased on commencement of nadolol.

The patient experienced 22 TLOC episodes before diagnosis – most likely from self-terminating VT.

With widespread availability of effective treatments to reduce the risk of sudden cardiac death in such conditions, clinicians should always remember how the ECG is an essential investigation every time a patient presents with TLOC.