Recurrent syncope with seizure-like features: the role of emergency monitoring in revealing intermittent AV block
摘要
Recurrent syncope with seizure-like stiffening may mimic epilepsy or neurological disorders, and when routine tests are repeatedly normal, intermittent arrhythmia can be easily overlooked.
Case presentationWe report a case of a 65-year-old man with hypertension, hyperuricaemia, dyslipidaemia, and asthma who experienced recurrent syncopal episodes over one month. He presented several times to emergency departments and tertiary hospitals. Neurological and cardiovascular investigations—including brain MRI, echocardiography, coronary angiography, laboratory tests, and a previous Holter ECG—were consistently unremarkable. The initial diagnosis was hypertensive crisis based on marked post-event blood pressure surges, which was later recognized as a secondary phenomena rather than the primary cause of syncope. On the index admission, continuous emergency monitoring captured a sinus arrest of ~ 17 s with absent arterial pulse waveform, followed by bradyarrhythmia. Post-event blood pressure spiked to 220/110 mmHg. A repeat Holter ECG confirmed intermittent Mobitz II and complete AV block with asystole up to 18.6 s. EEG, performed during this admission to exclude epilepsy, was normal. A dual-chamber permanent pacemaker was implanted with complete resolution of symptoms (Shen et al, Circulation 136(5):e60-e122, 2017; Kusumoto et al, Circulation 140(8): e382-e482, 2019; Brignole et al, Eur Heart J 39(21):1883-1948, 2018).
ConclusionThis case demonstrates how intermittent AV block may masquerade as seizure or hypertensive crisis, underlining the critical role of emergency department monitoring and prolonged ECG recording in recurrent unexplained syncope.