Late-onset sick sinus syndrome after carbon monoxide poisoning

Carbon monoxide (CO) is a known, potent poisonous gas that causes hypoxaemia be-cause of its high affinity for haemoglobin. It also induces inflammatory responses that cause tissue injury, particularly to the nervous and cardiovascular systems. Here we present a case of late-onset sick sinus syndrome (SSS) after CO poisoning. Ar-rhythmia during the acute phase has been recorded in the literature, but to the best of our knowledge, this is the first report of late-onset SSS. Late-onset neuropathy after CO poisoning is well known, and it seems that a similar mechanism develops in car-diac conduction after CO poisoning. This report highlights the importance of follow-up for arrhythmia after CO poisoning.