This electrocardiogram shows a non-specific intraventricular conduction delay. It is reflected by a QRS duration of 0.14 seconds that does not fulfill the classic criteria for left or right bundle brach block. Note the increased voltage of the R waves in leads I, aVL with ST-T wave abnormalities, in these same leads. These changes suggest significant left ventricular hypertrophy, but in the presence of this conduction delay, there are no valid criteria for making this electrocardiographic diagnosis. Note also that left axis deviation is present as evidence by the predominantly negative QRS complex in lead II. Intraventricular conduction disturbances are often seen with significant myocardial disease, but do not suggest a specific etiology.