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.
Premature Atrial Complex (PAC) zCharacteristics zHeart Rate: dependent on the underlying rhythm zRhythm: irregular if PACs are present; underlying rhythm may be regular zPacemaker Site: ectopic site in the atria; underlying rhythm has its own pacemaker site zP Waves: earlier than next expected P wave; positive in