We report a case of 77 year old man who never complained cardiac symptoms, with progress septal myocardial infarction diagnosed by electrocardiographic signs and akinesia of the septum-apical segment, detected by echocardiography. He underwent a new echocardiographic examination that pointed out an aberrant papillary muscle in the left ventricle which base (19 mm) was situated on the middle of the anterior-septum and apex connected with the apical portion of the lateral wall, inducing a dissinergic movement of the septum-apical segment as for the adjacent wall segments and with a reduced sistolic thickening. An exercise myocardial perfusion scintigraphy (Tl 201) detected no reversible or irreversible uptake defects, continuous ecg monitoring and an exercise test did not show any ischemic event. We discuss the electrogenetic and wall motion implication due to an aberrant papillary muscle that can be errorly considered secondary to a progress myocardial infarction.