Electrocardiographic atrial complex and acute atrial myocardial infarction

Abstract The atrial complex was examined by use of standard and right atrial leads in 59 patients with acute myocardial infarction. Abnormal atrial complexes were found in standard leads in 17 patients, and in the right atrial lead in 29 patients. Abnormal atrial complexes were found more frequently in patients who had arrhythmias in the acute phase than in patients without arrhythmias. Ten patients died during the acute phase. Infarcts in the right atrium were found in all 7 patients whose right atrium was examined microscopically. Abnormal atrial complexes in the right atrial lead were found in patients with atrial infarcts, especially when the lateral atrial wall was involved.