Sometimes, when right ventricular hypertrophy follows the development of left ventricular hypertrophy, there is cancellation of the accentuated left ventricular forces associated with the left ventricular hypertrophy and the electrocardiogram may appear normal, or nearly normal. The ECG shown here is from a patient with severe mitral insufficiency, an enlarged dilated left ventricle and pulmonary hypertension. The right ventricle was also enlarged and there was significant tricuspid insufficiency. The electrocardiogram appears normal in spite of the documented biventricular enlargement and suggests that the electrocardiographic manifestations of left ventricular hypertrophy were cancelled by the subsequent development of right ventricular hypertrophy.