Left atrial appendage blood flow in a case of persistent atrial standstill

Persistent atrial standstill, characterized by absence of atrial activity on surface and intracavitary electrograms, absence of atrial mechanical activity, and inability to stimulate the atria electrically, is a rare disorder. Left atrial appendage blood flow has been reported to be related to P wave during sinus rhythm or local atrial electrogram during atrial fibrillation. However, distinct and periodical LAA blood flow was demonstrated in a patient with persistent atrial standstill by transesophageal echocardiography.