Right ventricular hypertrophy

Right ventricular hypertrophy due, in this case, to primary pulmonary hypertension. The characteristic features include marked right axis deviation (+210º which is equal to -150º), tall R wave in V1 (as part of a qR complex), delayed precordial transition zone with prominent S waves in leads V5 and V6, inverted T waves and ST depression in V1 to V3 consistent with right ventricular overload ("strain" pattern), and peaked P waves in lead II consistent with concomitant right atrial abnormality.