The echocardiographic diagnostic criteria of left ventricular pseudo-aneurysm are well established: the demonstration of a narrow-necked communication between the left ventricular cavity and the aneurysm and endocardial discontinuity at the site of myocardial rupture. The authors report two cases in which these criteria were fulfilled, leading to an echocardiographic diagnosis of pseudo-aneurysm which was erroneous as the operative findings were those of true left ventricular aneurysms.