Deep inspiration induced sinus arrest. An unusual manifestation in a patient with the sick sinus syndrome.
In a patient with the sick sinus syndrome and near syncope a prolonged sinus pause was documented and reproduced thereafter during sustained deep inspiration. Administration of intravenous atropine abolished this phenomenon, most probably indicating a hyperresponsiveness of the sinus node and AV junction to a vagotonic reflex.
D000368:Aged; D004562:Electrocardiography; D006801:Humans; D008297:Male; D012119:Respiration; D012804:Sick Sinus Syndrome / Q000150:complications / Q000503:physiopathology*; D012849:Sinoatrial Node / Q000503:physiopathology*; D013575:Syncope / Q000209:etiology; D014630:Vagus Nerve / Q000503:physiopathology