under contract means there is an offer on it already and the buyer and seller are negotiating back and forth to come to an agreement. if ya need any more help just e-mail me. Lori lspalletta Â· 1 decade ago
Premature atrial complexes are caused by abnormal electrical impulses transmitted by the atria (either of the upper chambers of the heart). The abnormal electrical impulses cause contractions of the upper chamber of the heart earlier than expected. Such premature beats are generally harmless. slide 1 of 7.
Atrial septal defects. ASD is one of the most common congenital cardiac anomalies and is associated with a high incidence of atrial arrhythmias that increase in frequency as the patient ages. The later in life the ASD is repaired, the more likely atrial arrhythmias are to develop.