Sinus Bradycardia and QT Interval Prolongation in West Nile Virus Encephalitis: A Case Report.

Cardiac arrhythmias were reported in cases of West Nile Virus (WNV) encephalitis; however, the underlying pathophysiology remains incompletely understood. We present a 67-year-old male with altered mental status, later diagnosed with WNV encephalitis. Hospital course was complicated by progressive sinus bradycardia and corrected QT (QTc) prolongation. These findings persisted despite the absence of classical causes and resolved only after improvement of the underlying encephalitis. After excluding classical causes, autonomic dysfunction is one of the proposed mechanisms behind cardiac arrhythmias in WNV encephalitis. Resolution of arrhythmias is expected after the improvement of underlying encephalitis and should be taken into consideration before proceeding for pacemaker placement or other cardiac intervention. Furthermore, this case highlights the importance of continuous cardiac monitoring in WNV encephalitis patients.