This electrocardiogram shows biventricular hypertrophy.
The characteristic features of right ventricular hypertrophy demonstrated here include: dominant R wave in lead V1 with no S wave present; ST-T wave abnormalities in the right sided leads V2 and V3 and a slight right axis, as reflected by the S wave in lead I being slightly larger than the R wave.
Left ventricular hypertrophy is demonstrated by the height of the R waves in left sided leads V4 through V6 in the presence of RVH, and the presence of ST-T abnormalities in the same leads.
Biventricular hypertrophy is often difficult to diagnose.